Internet Engineering Task Force (IETF) M. Boucadair, Ed.
Request for Comments: 9244 Orange
Category: Standards Track T. Reddy.K, Ed.
ISSN: 2070-1721 Akamai
E. Doron
Radware Ltd.
M. Chen
CMCC
J. Shallow
June 2022
Distributed Denial-of-Service Open Threat Signaling (DOTS) Telemetry
Abstract
This document aims to enrich the Distributed Denial-of-Service Open
Threat Signaling (DOTS) signal channel protocol with various
telemetry attributes, allowing for optimal Distributed Denial-of-
Service (DDoS) attack mitigation. It specifies the normal traffic
baseline and attack traffic telemetry attributes a DOTS client can
convey to its DOTS server in the mitigation request, the mitigation
status telemetry attributes a DOTS server can communicate to a DOTS
client, and the mitigation efficacy telemetry attributes a DOTS
client can communicate to a DOTS server. The telemetry attributes
can assist the mitigator in choosing the DDoS mitigation techniques
and performing optimal DDoS attack mitigation.
This document specifies two YANG modules: one for representing DOTS
telemetry message types and one for sharing the attack mapping
details over the DOTS data channel.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9244.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Revised BSD License text as described in Section 4.e of the
Trust Legal Provisions and are provided without warranty as described
in the Revised BSD License.
Table of Contents
1. Introduction
2. Terminology
3. DOTS Telemetry: Overview and Purpose
3.1. Need for More Visibility
3.2. Enhanced Detection
3.3. Efficient Mitigation
4. Design Overview
4.1. Overview of Telemetry Operations
4.2. Block-Wise Transfers
4.3. DOTS Multihoming Considerations
4.4. YANG Considerations
5. Generic Considerations
5.1. DOTS Client Identification
5.2. DOTS Gateways
5.3. Uri-Path Parameters and Empty Values
5.4. Controlling Configuration Data
5.5. Message Validation
5.6. A Note about Examples
6. Telemetry Operation Paths
7. DOTS Telemetry Setup Configuration
7.1. Telemetry Configuration
7.1.1. Retrieving the Current DOTS Telemetry Configuration
7.1.2. Conveying the DOTS Telemetry Configuration
7.1.3. Retrieving the Installed DOTS Telemetry Configuration
7.1.4. Deleting the DOTS Telemetry Configuration
7.2. Total Pipe Capacity
7.2.1. Conveying DOTS Client Domain Pipe Capacity
7.2.2. Retrieving Installed DOTS Client Domain Pipe Capacity
7.2.3. Deleting Installed DOTS Client Domain Pipe Capacity
7.3. Telemetry Baseline
7.3.1. Conveying DOTS Client Domain Baseline Information
7.3.2. Retrieving Installed Normal Traffic Baseline
Information
7.3.3. Deleting Installed Normal Traffic Baseline Information
7.4. Resetting the Installed Telemetry Setup
7.5. Conflict with Other DOTS Clients of the Same Domain
8. DOTS Pre-or-Ongoing-Mitigation Telemetry
8.1. Pre-or-Ongoing-Mitigation DOTS Telemetry Attributes
8.1.1. Target
8.1.2. Total Traffic
8.1.3. Total Attack Traffic
8.1.4. Total Attack Connections
8.1.5. Attack Details
8.1.6. Vendor Attack Mapping
8.2. From DOTS Clients to DOTS Servers
8.3. From DOTS Servers to DOTS Clients
9. DOTS Telemetry Mitigation Status Update
9.1. From DOTS Clients to DOTS Servers: Mitigation Efficacy DOTS
Telemetry Attributes
9.2. From DOTS Servers to DOTS Clients: Mitigation Status DOTS
Telemetry Attributes
10. Error Handling
11. YANG Modules
11.1. DOTS Signal Channel Telemetry YANG Module
11.2. Vendor Attack Mapping Details YANG Module
12. YANG/JSON Mapping Parameters to CBOR
13. IANA Considerations
13.1. DOTS Signal Channel CBOR Key Values
13.2. DOTS Signal Channel Conflict Cause Codes
13.3. DOTS Telemetry URIs and YANG Module Registrations
14. Security Considerations
14.1. DOTS Signal Channel Telemetry
14.2. Vendor Attack Mapping
15. References
15.1. Normative References
15.2. Informative References
Acknowledgments
Contributors
Authors' Addresses
1. Introduction
IT organizations and service providers are facing Distributed Denial-
of-Service (DDoS) attacks that fall into two broad categories:
1. Network-layer and transport-layer attacks target the victim's
infrastructure. These attacks are not necessarily aimed at
taking down the actual delivered services; rather, these attacks
prevent various network elements (routers, switches, firewalls,
transit links, and so on) from serving legitimate users' traffic.
The main method of such attacks is to send a large volume of
traffic (e.g., high-pps (packets per second) traffic) toward the
victim's infrastructure. Typically, attack volumes may vary from
a few hundred Mbps to hundreds of Gbps or even Tbps. Attacks are
commonly carried out leveraging botnets and attack reflectors for
amplification attacks (Section 3.1 of [RFC4732]) such as NTP
(Network Time Protocol), DNS (Domain Name System), SNMP (Simple
Network Management Protocol), or SSDP (Simple Service Discovery
Protocol).
2. Application-layer attacks target various applications. Typical
examples include attacks against HTTP/HTTPS, DNS, SIP (Session
Initiation Protocol), or SMTP (Simple Mail Transfer Protocol).
However, all applications with their port numbers open at network
edges can be attractive attack targets.
Application-layer attacks are considered more complex and harder
to categorize and are therefore harder to detect and mitigate
efficiently.
To compound the problem, attackers also leverage multi-vectored
attacks. These attacks are assembled from dynamic network-layer and
application-layer attack vectors and other tactics. As such,
multiple attack vectors formed by multiple attack types and volumes
are launched simultaneously toward a victim. Multi-vector attacks
are harder to detect and defend against. Multiple and simultaneous
mitigation techniques are needed to defeat such attack campaigns. It
is also common for attackers to change attack vectors right after a
successful mitigation, burdening their opponents with changing their
defense methods.
The conclusion derived from the aforementioned attack scenarios is
that modern attack detection and mitigation are most certainly
complicated and highly convoluted tasks. They demand a comprehensive
knowledge of the attack attributes and the normal behavior of the
targeted systems (including normal traffic patterns), as well as the
attacker's ongoing and past actions. Even more challenging,
retrieving all the analytics needed for detecting these attacks is
not simple with the industry's current reporting capabilities.
The Distributed Denial-of-Service Open Threat Signaling (DOTS) signal
channel protocol [RFC9132] is used to carry information about a
network resource or a network (or a part thereof) that is under a
DDoS attack. Such information is sent by a DOTS client to one or
multiple DOTS servers so that appropriate mitigation actions are
undertaken on traffic deemed suspicious. Various use cases are
discussed in [RFC8903].
DOTS clients can be integrated within a DDoS attack detector or
within network and security elements that have been actively engaged
with ongoing attacks. The DOTS client mitigation environment
determines that it is no longer possible or practical for it to
handle these attacks itself. This can be due to a lack of resources
or security capabilities, as derived from the complexities and
intensity of these attacks. In this circumstance, the DOTS client
has invaluable knowledge about the actual attacks that need to be
handled by its DOTS server(s). By enabling the DOTS client to share
this comprehensive knowledge of an ongoing attack under specific
circumstances, the DOTS server can drastically increase its ability
to accomplish successful mitigation. While the attack is being
handled by the mitigation resources associated with the DOTS server,
the DOTS server has knowledge about the ongoing attack mitigation.
The DOTS server can share this information with the DOTS client so
that the client can better assess and evaluate the actual mitigation
realized.
DOTS clients can send mitigation hints derived from attack details to
DOTS servers, with the full understanding that a DOTS server may
ignore mitigation hints, as described in [RFC8612] (Gen-004).
Mitigation hints will be transmitted across the DOTS signal channel,
as the data channel may not be functional during an attack. How a
DOTS server handles normal and attack traffic attributes, and
mitigation hints, is implementation specific.
Both DOTS clients and servers can benefit from this information by
presenting various information details in relevant management,
reporting, and portal systems.
This document defines DOTS telemetry attributes that can be conveyed
by DOTS clients to DOTS servers, and vice versa. The DOTS telemetry
attributes are not mandatory attributes of the DOTS signal channel
protocol [RFC9132]. When no limitation policy is provided to a DOTS
agent, it can signal available telemetry attributes to its peers in
order to optimize the overall mitigation service provisioned using
DOTS. The aforementioned policy can be, for example, agreed upon
during a service subscription (which is out of scope for this
document) to identify a subset of DOTS clients among those deployed
in a DOTS client domain that are allowed to send or receive telemetry
data.
Section 11.2 of this document specifies a YANG module that augments
the DOTS data channel [RFC8783] with information related to attack
details. Sharing such details during 'idle' time is meant to
optimize the data exchanged over the DOTS signal channel.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
The reader should be familiar with the terms defined in [RFC8612].
"DOTS telemetry" is defined as the collection of attributes that are
used to characterize the normal traffic baseline, attacks and their
mitigation measures, and any related information that may help in
enforcing countermeasures. "DOTS telemetry" is an optional set of
attributes that can be signaled in the DOTS signal channel protocol.
The Telemetry Setup Identifier (tsid) is an identifier that is
generated by DOTS clients to uniquely identify DOTS telemetry setup
configuration data. See Section 7.1.2 for more details.
The Telemetry Identifier (tmid) is an identifier that is generated by
DOTS clients to uniquely identify DOTS telemetry data that is
communicated prior to or during a mitigation. See Section 8.2 for
more details.
"Overlapped" lower numeric 'tsid' (or 'tmid') refers to the lower
'tsid' (or 'tmid') value of two overlapping telemetry requests.
The term "pipe" represents the maximum level of traffic that the DOTS
client domain can receive. Whether a "pipe" is mapped to one or a
group of network interfaces is deployment specific. For example,
each interconnection link may be considered as a specific pipe if the
DOTS server is hosted by each upstream provider, while the aggregate
of all links to connect to upstream network providers can be
considered by a DOTS client domain as a single pipe when
communicating with a DOTS server not hosted by these upstream
providers.
This document uses IANA-assigned Enterprise Numbers. These numbers
are also known as "Private Enterprise Numbers" and "SMI (Structure of
Management Information) Network Management Private Enterprise Codes"
[Private-Enterprise-Numbers].
The meanings of the symbols in YANG tree diagrams are defined in
[RFC8340] and [RFC8791].
Consistent with the convention set in Section 2 of [RFC8783], the
examples in Section 8.1.6 use "/restconf" as the discovered RESTCONF
API root path. Within these examples, some protocol header lines are
split into multiple lines for display purposes only. When a line
ends with a backslash ("\") as the last character, the line is
wrapped for display purposes. It is considered to be joined to the
next line by deleting the backslash, the following line break, and
the leading whitespace of the next line.
3. DOTS Telemetry: Overview and Purpose
Timely and effective signaling of up-to-date DDoS telemetry to all
elements involved in the mitigation process is essential and improves
the overall DDoS mitigation service's effectiveness. Bidirectional
feedback between DOTS agents is required for increased awareness by
each party of the attack and mitigation efforts, supporting a
superior and highly efficient attack mitigation service.
3.1. Need for More Visibility
When signaling a mitigation request, it is most certainly beneficial
for DOTS clients to signal to DOTS servers any knowledge regarding
ongoing attacks. This can happen in cases where DOTS clients are
asking DOTS servers for support in defending against attacks that
they have already detected and/or (partially) mitigated.
If attacks are already detected and categorized within a DOTS client
domain, the DOTS server, and its associated mitigation services, can
proactively benefit from this information and optimize the overall
service delivery. It is important to note that DOTS client domains'
and DOTS server domains' detection and mitigation approaches can be
different and can potentially result in different results and attack
classifications. The DDoS mitigation service treats the ongoing
attack details received from DOTS clients as hints and cannot
completely rely on or trust the attack details conveyed by DOTS
clients.
In addition to the DOTS server directly using telemetry data as
operational hints, the DOTS server's security operation team also
benefits from telemetry data. A basic requirement of security
operation teams is to be aware of and get visibility into the attacks
they need to handle. This holds especially for the case of ongoing
attacks, where DOTS telemetry provides data about the current attack
status. Even if some mitigation can be automated, operational teams
can use the DOTS telemetry information to be prepared for attack
mitigation and to assign the correct resources (e.g., operation
staff, networking resources, mitigation resources) for the specific
service. Similarly, security operations personnel at the DOTS client
side ask for feedback about their requests for protection.
Therefore, it is valuable for DOTS servers to share DOTS telemetry
with DOTS clients.
Mutual sharing of information is thus crucial for "closing the
mitigation loop" between DOTS clients and servers. For the server-
side team, it is important to confirm that the same attacks that the
DOTS server's mitigation resources are seeing are those for which a
DOTS client is requesting mitigation. For the DOTS client-side team,
it is important to realize that the DOTS clients receive the required
service -- for example, understanding that "I asked for mitigation of
two attacks, and my DOTS server detects and mitigates only one of
them." Cases of inconsistency in attack classification between DOTS
clients and servers can be highlighted, and maybe handled, using the
DOTS telemetry attributes.
In addition, management and orchestration systems, at both the DOTS
client and server sides, can use DOTS telemetry as feedback to
automate various control and management activities derived from
signaled telemetry information.
If the DOTS server's mitigation resources have the capabilities to
facilitate the DOTS telemetry, the DOTS server adapts its protection
strategy and activates the required countermeasures immediately
(automation enabled) for the sake of optimized attack mitigation
decisions and actions. Discussion regarding the interface from the
DOTS server to the mitigator to signal the telemetry data is out of
scope for this document.
3.2. Enhanced Detection
DOTS telemetry can also be used as input for determining what values
to use for the tuning parameters available on the mitigation
resources. During the last few years, DDoS attack detection
technologies have evolved from threshold-based detection (that is,
cases when all or specific parts of traffic cross a predefined
threshold for a certain period of time is considered as an attack) to
an "anomaly detection" approach. For the latter, it is required to
maintain rigorous learning of "normal" behavior, and an "anomaly" (or
an attack) is identified and categorized based on the knowledge about
the normal behavior and a deviation from this normal behavior.
Statistical and artificial intelligence algorithms (e.g., machine
learning) are used such that the actual traffic thresholds are
automatically calculated by learning the protected entity's normal
traffic behavior during 'idle' time (i.e., no mitigation is active).
The normal traffic characterization learned is referred to as the
"normal traffic baseline". An attack is detected when the victim's
actual traffic is deviating from this normal baseline pattern.
In addition, subsequent activities toward mitigating an attack are
much more challenging. The ability to distinguish legitimate traffic
from attacker traffic on a per-packet basis is complex. For example,
a packet may look "legitimate" and no attack signature can be
identified. The anomaly can be identified only after detailed
statistical analysis. DDoS attack mitigators use the normal baseline
during the mitigation of an attack to identify and categorize the
expected appearance of a specific traffic pattern. Particularly, the
mitigators use the normal baseline to recognize the "level of
normality" that needs to be achieved during the various mitigation
processes.
Normal baseline calculation is performed based on continuous learning
of the normal behavior of the protected entities. The minimum
learning period varies from hours to days and even weeks, depending
on the protected applications' behavior. The baseline cannot be
learned during active attacks because attack conditions do not
characterize the protected entities' normal behavior.
If the DOTS client has calculated the normal baseline of its
protected entities, signaling such information to the DOTS server
along with the attack traffic levels provides value. The DOTS server
benefits from this telemetry by tuning its mitigation resources with
the DOTS client's normal baseline. The DOTS server's mitigators use
the baseline to familiarize themselves with the attack victim's
normal behavior and target the baseline as the level of normality
they need to achieve. Fed with this information, the overall
mitigation performance is expected to be improved in terms of time to
mitigate, accuracy, and false-negative and false-positive rates.
Mitigation of attacks without having certain knowledge of normal
traffic can be inaccurate at best. This is especially true for
recursive signaling (see Section 3.2.3 of [RFC8811]). Given that
DOTS clients can be integrated in a highly diverse set of scenarios
and use cases, this emphasizes the need for knowledge of the behavior
of each DOTS client domain -- especially given that common global
thresholds for attack detection can almost never be realized. Each
DOTS client domain can have its own levels of traffic and normal
behavior. Without facilitating normal baseline signaling, it may be
very difficult for DOTS servers in some cases to detect and mitigate
the attacks accurately:
* It is important to emphasize that it is practically impossible for
the DOTS server's mitigators to calculate the normal baseline in
cases where they do not have any knowledge of the traffic
beforehand.
Of course, this information can be provided using out-of-band
mechanisms or manual configuration, at the risk of unmaintained
information becoming inaccurate as the network evolves and "normal"
patterns change. The use of a dynamic and collaborative means
between the DOTS client and server to identify and share key
parameters for the sake of efficient DDoS protection is valuable.
3.3. Efficient Mitigation
During a high-volume attack, DOTS client pipes can be totally
saturated. DOTS clients ask their DOTS servers to handle the attack
upstream so that DOTS client pipes return to a reasonable load level
(normal pattern, ideally). At this point, it is essential to ensure
that the mitigator does not overwhelm the DOTS client pipes by
sending back large volumes of "clean traffic", or what it believes is
"clean". This can happen when the mitigator has not managed to
detect and mitigate all the attacks launched toward the DOTS client
domain.
In this case, it can be valuable to DOTS clients to signal to DOTS
servers the total pipe capacity, which is the level of traffic the
DOTS client domain can absorb from its upstream network. This is
usually the circuit size, which includes all the packet overheads.
Dynamic updates of the condition of pipes between DOTS agents while
they are under a DDoS attack are essential (e.g., where multiple DOTS
clients share the same physical connectivity pipes). The DOTS server
should activate other mechanisms to ensure that it does not allow the
DOTS client domain's pipes to be saturated unintentionally. The
rate-limit action defined in [RFC8783] is a reasonable candidate to
achieve this objective; the DOTS client can indicate the type(s) of
traffic (such as ICMP, UDP, TCP port number 80) it prefers to limit.
The rate-limit action can be controlled via the signal channel
[RFC9133] even when the pipe is overwhelmed.
4. Design Overview
4.1. Overview of Telemetry Operations
The DOTS protocol suite is divided into two logical channels: the
signal channel [RFC9132] and data channel [RFC8783]. This division
is due to the vastly different requirements placed upon the traffic
they carry. The DOTS signal channel must remain available and usable
even in the face of attack traffic that might, for example, saturate
one direction of the links involved, rendering acknowledgment-based
mechanisms unreliable and strongly incentivizing messages to be small
enough to be contained in a single IP packet (Section 2.2 of
[RFC8612]). In contrast, the DOTS data channel is available for
high-bandwidth data transfer before or after an attack, using more
conventional transport protocol techniques (Section 2.3 of
[RFC8612]). It is generally preferable to perform advance
configuration over the DOTS data channel, including configuring
aliases for static or nearly static data sets such as sets of network
addresses/prefixes that might be subject to related attacks. This
design helps to optimize the use of the DOTS signal channel for the
small messages that are important to deliver during an attack. As a
reminder, the DOTS signal channel and data channel both require
secure communication channels (Section 11 of [RFC9132] and Section 10
of [RFC8783]).
Telemetry information has aspects that correspond to both operational
modes (i.e., signal channel and data channel): there is certainly a
need to convey updated information about ongoing attack traffic and
targets during an attack, so as to convey detailed information about
mitigation status and inform updates to mitigation strategy in the
face of adaptive attacks. However, it is also useful to provide
mitigation services with a picture of normal or "baseline" traffic
toward potential targets to aid in detecting when incoming traffic
deviates from normal into being an attack. Also, one might populate
a "database" of classifications of known types of attacks so that a
short attack identifier can be used during an attack period to
describe an observed attack. This specification does make provision
for use of the DOTS data channel for the latter function
(Section 8.1.6) but otherwise retains most telemetry functionality in
the DOTS signal channel.
Note that it is a functional requirement to convey information about
ongoing attack traffic during an attack, and information about
baseline traffic uses an essentially identical data structure that is
naturally defined to sit next to the description of attack traffic.
The related telemetry setup information used to parameterize actual
traffic data is also sent over the signal channel, out of expediency.
This document specifies an extension to the DOTS signal channel
protocol. Considerations about how to establish, maintain, and make
use of the DOTS signal channel are specified in [RFC9132].
Once the DOTS signal channel is established, DOTS clients that
support the DOTS telemetry extension proceed with the telemetry setup
configuration (e.g., measurement interval, telemetry notification
interval, pipe capacity, normal traffic baseline) as detailed in
Section 7. DOTS agents can then include DOTS telemetry attributes
using the DOTS signal channel (Section 8.1). A DOTS client can use
separate messages to share with its DOTS server(s) a set of telemetry
data bound to an ongoing mitigation (Section 8.2). Also, a DOTS
client that is interested in receiving telemetry notifications
related to some of its resources follows the procedure defined in
Section 8.3. A DOTS client that receives such notifications can then
decide to send a mitigation request if an attack cannot be mitigated
locally within the DOTS client domain.
Aggregate DOTS telemetry data can also be included in efficacy update
(Section 9.1) or mitigation update (Section 9.2) messages.
4.2. Block-Wise Transfers
DOTS clients can use a block-wise transfer [RFC7959] with the
recommendation detailed in Section 4.4.2 of [RFC9132] to control the
size of a response when the data to be returned does not fit within a
single datagram.
DOTS clients can also use the Constrained Application Protocol (CoAP)
Block1 Option in a PUT request (Section 2.5 of [RFC7959]) to initiate
large transfers, but these Block1 transfers are likely to fail if the
inbound "pipe" is running full because the transfer requires a
message from the server for each block, which would likely be lost in
the incoming flood. Consideration needs to be made to try to fit
this PUT into a single transfer or to separate out the PUT into
several discrete PUTs where each of them fits into a single packet.
Q-Block1 and Q-Block2 Options that are similar to the CoAP Block1 and
Block2 Options, but enable robust transmissions of big blocks of data
with less packet interchanges using NON messages, are defined in
[RFC9177]. DOTS implementations can consider the use of Q-Block1 and
Q-Block2 Options [DOTS-Robust-Blocks].
4.3. DOTS Multihoming Considerations
Considerations for multihomed DOTS clients to select which DOTS
server to contact and which IP prefixes to include in a telemetry
message to a given peer DOTS server are discussed in
[DOTS-Multihoming]. For example, if each upstream network exposes a
DOTS server and the DOTS client maintains DOTS channels with all of
them, only the information related to prefixes assigned by an
upstream network to the DOTS client domain will be signaled via the
DOTS channel established with the DOTS server of that upstream
network.
Considerations related to whether (and how) a DOTS client gleans some
telemetry information (e.g., attack details) it receives from a first
DOTS server and shares it with a second DOTS server are
implementation and deployment specific.
4.4. YANG Considerations
Telemetry messages exchanged between DOTS agents are serialized using
Concise Binary Object Representation (CBOR) [RFC8949]. CBOR-encoded
payloads are used to carry signal-channel-specific payload messages
that convey request parameters and response information such as
errors.
This document specifies a YANG module [RFC7950] for representing DOTS
telemetry message types (Section 11.1). All parameters in the
payload of the DOTS signal channel are mapped to CBOR types as
specified in Section 12. As a reminder, Section 3 of [RFC9132]
defines the rules for mapping YANG-modeled data to CBOR.
The DOTS telemetry module (Section 11.1) is not intended to be used
via the Network Configuration Protocol (NETCONF) / RESTCONF for DOTS
server management purposes. It serves only to provide a data model
and encoding following [RFC8791]. Server deviations (Section 5.6.3
of [RFC7950]) are strongly discouraged, as the peer DOTS agent does
not have the means to retrieve the list of deviations and thus
interoperability issues are likely to be encountered.
The DOTS telemetry module (Section 11.1) uses "enumerations" rather
than "identities" to define units, samples, and intervals because
otherwise the namespace identifier "ietf-dots-telemetry" must be
included when a telemetry attribute is included (e.g., in a
mitigation efficacy update). The use of "identities" is thus
suboptimal from the standpoint of message compactness, as message
compactness is one of the key requirements for DOTS signal channel
messages.
The DOTS telemetry module (Section 11.1) includes some lists for
which no "key" statement is included. This behavior is compliant
with [RFC8791]. The reason for not including these keys is that they
are not included in the message body of DOTS requests; such keys are
included as mandatory Uri-Paths in requests (Sections 7 and 8).
Otherwise, whenever a "key" statement is used in the module, the same
definition as the definition provided in Section 7.8.2 of [RFC7950]
is assumed.
Some parameters (e.g., low-percentile values) may be associated with
different YANG types (e.g., decimal64 and yang:gauge64). To easily
distinguish the types of these parameters while using meaningful
names, the following suffixes are used:
+========+==============+==================+
| Suffix | YANG Type | Example |
+========+==============+==================+
| -g | yang:gauge64 | low-percentile-g |
+--------+--------------+------------------+
| -c | container | connection-c |
+--------+--------------+------------------+
| -ps | per second | connection-ps |
+--------+--------------+------------------+
Table 1: Suffixes and YANG Types
The full tree diagram of the DOTS telemetry module can be generated
using the "pyang" tool [PYANG]. That tree is not included here
because it is too long (Section 3.3 of [RFC8340]). Instead, subtrees
are provided for the reader's convenience.
In order to optimize the data exchanged over the DOTS signal channel,
this document specifies a second YANG module ("ietf-dots-mapping";
see Section 11.2) that augments the DOTS data channel [RFC8783].
This augmentation can be used during 'idle' time to share the attack
mapping details (Section 8.1.5). DOTS clients can use tools, e.g.,
the YANG Library [RFC8525], to retrieve the list of features and
deviations supported by the DOTS server over the data channel.
5. Generic Considerations
5.1. DOTS Client Identification
Following the rules in Section 4.4.1 of [RFC9132], a unique
identifier is generated by a DOTS client to prevent request
collisions ('cuid').
As a reminder, Section 4.4.1.3 of [RFC9132] forbids 'cuid' to be
returned in a response message body.
5.2. DOTS Gateways
DOTS gateways may be located between DOTS clients and servers. The
considerations elaborated in Section 4.4.1 of [RFC9132] must be
followed. In particular, the 'cdid' attribute is used to
unambiguously identify a DOTS client domain.
As a reminder, Section 4.4.1.3 of [RFC9132] forbids 'cdid' (if
present) to be returned in a response message body.
5.3. Uri-Path Parameters and Empty Values
Uri-Path parameters and attributes with empty values MUST NOT be
present in a request. The presence of such an empty value renders
the entire containing message invalid.
5.4. Controlling Configuration Data
The DOTS server follows the same considerations discussed in
Section 4.5.3 of [RFC9132] for managing DOTS telemetry configuration
freshness and notifications.
Likewise, a DOTS client may control the selection of configuration
and non-configuration data nodes when sending a GET request by means
of the 'c' (content) Uri-Query option and following the procedure
specified in Section 4.4.2 of [RFC9132]. These considerations are
not reiterated in the following sections.
5.5. Message Validation
The authoritative references for validating telemetry messages
exchanged over the DOTS signal channel are Sections 7, 8, and 9
together with the mapping table provided in Section 12. The
structure of telemetry message bodies is represented as a YANG data
structure (Section 11.1).
5.6. A Note about Examples
Examples are provided for illustration purposes. This document does
not aim to provide a comprehensive list of message examples.
JSON encoding of YANG-modeled data is used to illustrate the various
telemetry operations. To ease readability, parameter names and their
JSON types are thus used in the examples rather than their CBOR key
values and CBOR types following the mappings in Section 12. These
conventions are inherited from [RFC9132].
The examples use Enterprise Number 32473, which is defined for
documentation use; see [RFC5612].
6. Telemetry Operation Paths
As discussed in Section 4.2 of [RFC9132], each DOTS operation is
indicated by a path suffix that indicates the intended operation.
The operation path is appended to the path prefix to form the URI
used with a CoAP request to perform the desired DOTS operation. The
following telemetry path suffixes are defined (Table 2):
+=================+================+===========+
| Operation | Operation Path | Details |
+=================+================+===========+
| Telemetry Setup | /tm-setup | Section 7 |
+-----------------+----------------+-----------+
| Telemetry | /tm | Section 8 |
+-----------------+----------------+-----------+
Table 2: DOTS Telemetry Operations
Consequently, the "ietf-dots-telemetry" YANG module defined in
Section 11.1 defines a data structure to represent new DOTS message
types called 'telemetry-setup' and 'telemetry'. The tree structure
is shown in Figure 1. More details are provided in Sections 7 and 8
about the exact structure of 'telemetry-setup' and 'telemetry'
message types.
structure dots-telemetry:
+-- (telemetry-message-type)?
+--:(telemetry-setup)
| ...
| +-- telemetry* []
| ...
| +-- (setup-type)?
| +--:(telemetry-config)
| | ...
| +--:(pipe)
| | ...
| +--:(baseline)
| ...
+--:(telemetry)
...
Figure 1: New DOTS Message Types (YANG Tree Structure)
DOTS implementations MUST support the Observe Option [RFC7641] for
'tm' (Section 8).
7. DOTS Telemetry Setup Configuration
In reference to Figure 1, a DOTS telemetry setup message MUST include
only telemetry-related configuration parameters (Section 7.1),
information about DOTS client domain pipe capacity (Section 7.2), or
information about the telemetry traffic baseline (Section 7.3). As
such, requests that include a mix of telemetry configuration, pipe
capacity, and traffic baseline information MUST be rejected by DOTS
servers with a 4.00 (Bad Request) Response Code.
A DOTS client can reset all installed DOTS telemetry setup
configuration data following the considerations detailed in
Section 7.4.
A DOTS server may detect conflicts when processing requests related
to DOTS client domain pipe capacity or telemetry traffic baseline
information with requests from other DOTS clients of the same DOTS
client domain. More details are included in Section 7.5.
Telemetry setup configuration is bound to a DOTS client domain. DOTS
servers MUST NOT expect DOTS clients to send regular requests to
refresh the telemetry setup configuration. Any available telemetry
setup configuration is valid until the DOTS server ceases to service
a DOTS client domain. DOTS servers MUST NOT reset 'tsid' because a
session failed with a DOTS client. DOTS clients update their
telemetry setup configuration upon change of a parameter that may
impact attack mitigation.
DOTS telemetry setup configuration request and response messages are
marked as Confirmable messages (Section 2.1 of [RFC7252]).
7.1. Telemetry Configuration
DOTS telemetry uses several percentile values to provide a picture of
a traffic distribution overall, as opposed to just a single snapshot
of observed traffic at a single point in time. Modeling raw traffic
flow data as a distribution and describing that distribution entails
choosing a measurement period that the distribution will describe,
and a number of sampling intervals, or "buckets", within that
measurement period. Traffic within each bucket is treated as a
single event (i.e., averaged), and then the distribution of buckets
is used to describe the distribution of traffic over the measurement
period. A distribution can be characterized by statistical measures
(e.g., mean, median, and standard deviation) and also by reporting
the value of the distribution at various percentile levels of the
data set in question (e.g., "quartiles" that correspond to 25th,
50th, and 75th percentiles). More details about percentile values
and their computation are found in Section 11.3 of [RFC2330].
DOTS telemetry uses up to three percentile values, plus the overall
peak, to characterize traffic distributions. Which percentile
thresholds are used for these "low-percentile", "mid-percentile", and
"high-percentile" values is configurable. Default values are defined
in Section 7.1.2.
A DOTS client can negotiate with its server(s) a set of telemetry
configuration parameters to be used for telemetry. Such parameters
include:
* Percentile-related measurement parameters. In particular,
'measurement-interval' defines the period during which percentiles
are computed, while 'measurement-sample' defines the time
distribution for measuring values that are used to compute
percentiles.
* Measurement units.
* Acceptable percentile values.
* Telemetry notification interval.
* Acceptable server-originated telemetry.
7.1.1. Retrieving the Current DOTS Telemetry Configuration
A GET request is used to obtain acceptable and current telemetry
configuration parameters on the DOTS server. This request may
include a 'cdid' Uri-Path when the request is relayed by a DOTS
gateway. An example of such a GET request (without a gateway) is
depicted in Figure 2.
Header: GET (Code=0.01)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Figure 2: GET to Retrieve the Current and Acceptable DOTS Telemetry
Configuration
Upon receipt of such a request, and assuming that no error is
encountered when processing the request, the DOTS server replies with
a 2.05 (Content) response that conveys the telemetry parameters that
are acceptable to the DOTS server, any pipe information
(Section 7.2), and the current baseline information (Section 7.3)
maintained by the DOTS server for this DOTS client. The tree
structure of the response message body is provided in Figure 3.
DOTS servers that support the capability of sending telemetry
information to DOTS clients prior to or during a mitigation
(Section 9.2) set 'server-originated-telemetry' under 'max-config-
values' to 'true' ('false' is used otherwise). If 'server-
originated-telemetry' is not present in a response, this is
equivalent to receiving a response with 'server-originated-telemetry'
set to 'false'.
structure dots-telemetry:
+-- (telemetry-message-type)?
+--:(telemetry-setup)
| +-- (direction)?
| | +--:(server-to-client-only)
| | +-- max-config-values
| | | +-- measurement-interval? interval
| | | +-- measurement-sample? sample
| | | +-- low-percentile? percentile
| | | +-- mid-percentile? percentile
| | | +-- high-percentile? percentile
| | | +-- server-originated-telemetry? boolean
| | | +-- telemetry-notify-interval? uint16
| | +-- min-config-values
| | | +-- measurement-interval? interval
| | | +-- measurement-sample? sample
| | | +-- low-percentile? percentile
| | | +-- mid-percentile? percentile
| | | +-- high-percentile? percentile
| | | +-- telemetry-notify-interval? uint16
| | +-- supported-unit-classes
| | | +-- unit-config* [unit]
| | | +-- unit unit-class
| | | +-- unit-status boolean
| | +-- supported-query-type* query-type
| +-- telemetry* []
| +-- (direction)?
| | +--:(server-to-client-only)
| | +-- tsid? uint32
| +-- (setup-type)?
| +--:(telemetry-config)
| | +-- current-config
| | +-- measurement-interval? interval
| | +-- measurement-sample? sample
| | +-- low-percentile? percentile
| | +-- mid-percentile? percentile
| | +-- high-percentile? percentile
| | +-- unit-config* [unit]
| | | +-- unit unit-class
| | | +-- unit-status boolean
| | +-- server-originated-telemetry? boolean
| | +-- telemetry-notify-interval? uint16
| +--:(pipe)
| | ...
| +--:(baseline)
| ...
+--:(telemetry)
...
Figure 3: Telemetry Configuration Tree Structure
When both 'min-config-values' and 'max-config-values' attributes are
present, the values carried in 'max-config-values' attributes MUST be
greater than or equal to their counterparts in 'min-config-values'
attributes.
7.1.2. Conveying the DOTS Telemetry Configuration
A PUT request is used to convey the configuration parameters for the
telemetry data (e.g., low-, mid-, or high-percentile values). For
example, a DOTS client may contact its DOTS server to change the
default percentile values used as the baseline for telemetry data.
Figure 3 lists the attributes that can be set by a DOTS client in
such a PUT request. An example of a DOTS client that modifies all
percentile reference values is shown in Figure 4.
| Note: The payload of the message depicted in Figure 4 is CBOR-
| encoded as indicated by setting the Content-Format entry to
| "application/dots+cbor" (Section 10.3 of [RFC9132]). However,
| and for the sake of better readability, the example (and other
| similar figures depicting a DOTS telemetry message body)
| follows the conventions set in Section 5.6: use the JSON names
| and types defined in Section 12.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=123"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"current-config": {
"low-percentile": "5.00",
"mid-percentile": "65.00",
"high-percentile": "95.00"
}
}
]
}
}
Figure 4: PUT to Convey the DOTS Telemetry Configuration,
Depicted as per Section 5.6
'cuid' is a mandatory Uri-Path parameter for PUT requests.
The following additional Uri-Path parameter is defined:
tsid: The Telemetry Setup Identifier is an identifier for the DOTS
telemetry setup configuration data represented as an integer.
This identifier MUST be generated by DOTS clients. 'tsid' values
MUST increase monotonically whenever new configuration parameters
(not just for changed values) need to be conveyed by the DOTS
client.
The procedure specified in Section 4.4.1 of [RFC9132] for 'mid'
rollover MUST also be followed for 'tsid' rollover.
This is a mandatory attribute. 'tsid' MUST appear after 'cuid' in
the Uri-Path options.
'cuid' and 'tsid' MUST NOT appear in the PUT request message body.
At least one configurable attribute MUST be present in the PUT
request.
A PUT request with a higher numeric 'tsid' value overrides the DOTS
telemetry configuration data installed by a PUT request with a lower
numeric 'tsid' value. To avoid maintaining a long list of 'tsid'
requests for requests carrying telemetry configuration data from a
DOTS client, the lower numeric 'tsid' MUST be automatically deleted
and no longer be available at the DOTS server.
The DOTS server indicates the result of processing the PUT request
using the following Response Codes:
* If the request is missing a mandatory attribute, does not include
'cuid' or 'tsid' Uri-Path parameters, or contains one or more
invalid or unknown parameters, a 4.00 (Bad Request) Response Code
MUST be returned in the response.
* If the DOTS server does not find the 'tsid' parameter value
conveyed in the PUT request in its configuration data and if the
DOTS server has accepted the configuration parameters, then a 2.01
(Created) Response Code MUST be returned in the response.
* If the DOTS server finds the 'tsid' parameter value conveyed in
the PUT request in its configuration data and if the DOTS server
has accepted the updated configuration parameters, a 2.04
(Changed) Response Code MUST be returned in the response.
* If any of the enclosed configurable attribute values are not
acceptable to the DOTS server (Section 7.1.1), a 4.22
(Unprocessable Entity) Response Code MUST be returned in the
response.
The DOTS client may retry and send the PUT request with updated
attribute values acceptable to the DOTS server.
By default, low-percentile (10th percentile), mid-percentile (50th
percentile), high-percentile (90th percentile), and peak (100th
percentile) values are used to represent telemetry data.
Nevertheless, a DOTS client can disable some percentile types (low,
mid, high). In particular, setting 'low-percentile' to "0.00"
indicates that the DOTS client is not interested in receiving low-
percentiles. Likewise, setting 'mid-percentile' (or 'high-
percentile') to the same value as 'low-percentile' (or 'mid-
percentile') indicates that the DOTS client is not interested in
receiving mid-percentiles (or high-percentiles). For example, a DOTS
client can send the request depicted in Figure 5 to inform the server
that it is interested in receiving only high-percentiles. This
assumes that the client will only use that percentile type when
sharing telemetry data with the server.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=124"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"current-config": {
"low-percentile": "0.00",
"mid-percentile": "0.00",
"high-percentile": "95.00"
}
}
]
}
}
Figure 5: PUT to Disable Low- and Mid-Percentiles, Depicted as
per Section 5.6
DOTS clients can also configure the unit class(es) to be used for
traffic-related telemetry data among the following supported unit
classes: packets per second, bits per second, and bytes per second.
Supplying both bits per second and bytes per second unit classes is
allowed for a given set of telemetry data. However, receipt of
conflicting values is treated as invalid parameters and rejected with
a 4.00 (Bad Request) Response Code.
DOTS clients that are interested in receiving pre-or-ongoing-
mitigation telemetry ('pre-or-ongoing-mitigation') information from a
DOTS server (Section 9.2) MUST set 'server-originated-telemetry' to
'true'. If 'server-originated-telemetry' is not present in a PUT
request, this is equivalent to receiving a request with 'server-
originated-telemetry' set to 'false'. An example of a request to
enable pre-or-ongoing-mitigation telemetry from DOTS servers is shown
in Figure 6.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=125"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"current-config": {
"server-originated-telemetry": true
}
}
]
}
}
Figure 6: PUT to Enable Pre-or-Ongoing-Mitigation Telemetry from
the DOTS Server, Depicted as per Section 5.6
7.1.3. Retrieving the Installed DOTS Telemetry Configuration
A DOTS client may issue a GET message with a 'tsid' Uri-Path
parameter to retrieve the current DOTS telemetry configuration. An
example of such a request is depicted in Figure 7.
Header: GET (Code=0.01)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=123"
Figure 7: GET to Retrieve the Current DOTS Telemetry Configuration
If the DOTS server does not find the 'tsid' Uri-Path value conveyed
in the GET request in its configuration data for the requesting DOTS
client, it MUST respond with a 4.04 (Not Found) error Response Code.
7.1.4. Deleting the DOTS Telemetry Configuration
A DELETE request is used to delete the installed DOTS telemetry
configuration data (Figure 8). 'cuid' and 'tsid' are mandatory Uri-
Path parameters for such DELETE requests.
Header: DELETE (Code=0.04)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=123"
Figure 8: Deleting the Telemetry Configuration
The DOTS server resets the DOTS telemetry configuration back to the
default values and acknowledges a DOTS client's request to remove the
DOTS telemetry configuration using a 2.02 (Deleted) Response Code. A
2.02 (Deleted) Response Code is returned even if the 'tsid' parameter
value conveyed in the DELETE request does not exist in its
configuration data before the request.
Section 7.4 discusses the procedure to reset all DOTS telemetry setup
configuration data.
7.2. Total Pipe Capacity
A DOTS client can communicate to the DOTS server(s) its DOTS client
domain pipe information. The tree structure of the pipe information
is shown in Figure 9.
structure dots-telemetry:
+-- (telemetry-message-type)?
+--:(telemetry-setup)
| ...
| +-- telemetry* []
| +-- (direction)?
| | +--:(server-to-client-only)
| | +-- tsid? uint32
| +-- (setup-type)?
| +--:(telemetry-config)
| | ...
| +--:(pipe)
| | +-- total-pipe-capacity* [link-id unit]
| | +-- link-id nt:link-id
| | +-- capacity uint64
| | +-- unit unit
| +--:(baseline)
| ...
+--:(telemetry)
...
Figure 9: Pipe Tree Structure
A DOTS client domain pipe is defined as a list of limits on
(incoming) traffic volume ('total-pipe-capacity') that can be
forwarded over ingress interconnection links of a DOTS client domain.
Each of these links is identified with a 'link-id' [RFC8345].
The unit used by a DOTS client when conveying pipe information is
captured in the 'unit' attribute. The DOTS client MUST auto-scale so
that the appropriate unit is used. That is, for a given unit class,
the DOTS client uses the largest unit that gives a value greater than
one. As such, only one unit per unit class is allowed.
7.2.1. Conveying DOTS Client Domain Pipe Capacity
Considerations similar to those specified in Section 7.1.2 are
followed, with one exception:
* The relative order of two PUT requests carrying DOTS client domain
pipe attributes from a DOTS client is determined by comparing
their respective 'tsid' values. If these two requests have
overlapping 'link-id' and 'unit' settings, the PUT request with a
higher numeric 'tsid' value will override the request with a lower
numeric 'tsid' value. The overlapped lower numeric 'tsid' MUST be
automatically deleted and no longer be available.
DOTS clients SHOULD minimize the number of active 'tsid's used for
pipe information. In order to avoid maintaining a long list of
'tsid's for pipe information, it is RECOMMENDED that DOTS clients
include in any request to update information related to a given link
the information regarding other links (already communicated using a
lower 'tsid' value). By doing so, this update request will override
these existing requests and hence optimize the number of 'tsid'
requests per DOTS client.
| Note: This assumes that all link information can fit in one
| single message.
As an example of configuring pipe information, a DOTS client managing
a single-homed domain (Figure 10) can send a PUT request (shown in
Figure 11) to communicate the capacity of "link1" used to connect to
its ISP.
,--,--,--. ,--,--,--.
,-' `-. ,-' `-.
( DOTS Client )=====( ISP#A )
`-. Domain ,-' link1 `-. ,-'
`--'--'--' `--'--'--'
Figure 10: Single-Homed DOTS Client Domain
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=126"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"total-pipe-capacity": [
{
"link-id": "link1",
"capacity": "500",
"unit": "megabit-ps"
}
]
}
]
}
}
Figure 11: Example of a PUT Request to Convey Pipe Information
(Single-Homed), Depicted as per Section 5.6
DOTS clients may be instructed to signal a link aggregate instead of
individual links. For example, a DOTS client that manages a DOTS
client domain having two interconnection links with an upstream ISP
(Figure 12) can send a PUT request (shown in Figure 13) to
communicate the aggregate link capacity with its ISP. Signaling
individual or aggregate link capacity is deployment specific.
,--,--,--. ,--,--,--.
,-' `-.===== ,-' `-.
( DOTS Client ) ( ISP#C )
`-. Domain ,-'====== `-. ,-'
`--'--'--' `--'--'--'
Figure 12: DOTS Client Domain with Two Interconnection Links
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=hmcpH87lmPGsSTjkhXCbin"
Uri-Path: "tsid=896"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"total-pipe-capacity": [
{
"link-id": "aggregate",
"capacity": "700",
"unit": "megabit-ps"
}
]
}
]
}
}
Figure 13: Example of a PUT Request to Convey Pipe Information
(Aggregated Link), Depicted as per Section 5.6
Now consider that the DOTS client domain was upgraded to connect to
an additional ISP (e.g., ISP#B in Figure 14); the DOTS client can
inform a DOTS server that is not hosted with ISP#A and ISP#B domains
about this update by sending the PUT request depicted in Figure 15.
This request also includes information related to "link1" even if
that link is not upgraded. Upon receipt of this request, the DOTS
server removes the request with 'tsid=126' and updates its
configuration base to maintain two links (link1 and link2).
,--,--,--.
,-' `-.
( ISP#B )
`-. ,-'
`--'--'--'
||
|| link2
,--,--,--. ,--,--,--.
,-' `-. ,-' `-.
( DOTS Client )=====( ISP#A )
`-. Domain ,-' link1 `-. ,-'
`--'--'--' `--'--'--'
Figure 14: Multihomed DOTS Client Domain
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=127"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"total-pipe-capacity": [
{
"link-id": "link1",
"capacity": "500",
"unit": "megabit-ps"
},
{
"link-id": "link2",
"capacity": "500",
"unit": "megabit-ps"
}
]
}
]
}
}
Figure 15: Example of a PUT Request to Convey Pipe Information
(Multihomed), Depicted as per Section 5.6
A DOTS client can delete a link by sending a PUT request with the
'capacity' attribute set to "0" if other links are still active for
the same DOTS client domain. For example, if a DOTS client domain
re-homes (that is, it changes its ISP), the DOTS client can inform
its DOTS server about this update (e.g., from the network
configuration in Figure 10 to the network configuration shown in
Figure 16) by sending the PUT request depicted in Figure 17. Upon
receipt of this request, and assuming that no error is encountered
when processing the request, the DOTS server removes "link1" from its
configuration bases for this DOTS client domain. Note that if the
DOTS server receives a PUT request with a 'capacity' attribute set to
"0" for all included links, it MUST reject the request with a 4.00
(Bad Request) Response Code. Instead, the DOTS client can use a
DELETE request to delete all links (Section 7.2.3).
,--,--,--.
,-' `-.
( ISP#B )
`-. ,-'
`--'--'--'
||
|| link2
,--,--,--.
,-' `-.
( DOTS Client )
`-. Domain ,-'
`--'--'--'
Figure 16: Multihomed DOTS Client Domain
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=128"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"total-pipe-capacity": [
{
"link-id": "link1",
"capacity": "0",
"unit": "megabit-ps"
},
{
"link-id": "link2",
"capacity": "500",
"unit": "megabit-ps"
}
]
}
]
}
}
Figure 17: Example of a PUT Request to Convey Pipe Information
(Multihomed), Depicted as per Section 5.6
7.2.2. Retrieving Installed DOTS Client Domain Pipe Capacity
A GET request with a 'tsid' Uri-Path parameter is used to retrieve
the specific information related to an installed DOTS client domain
pipe. The same procedure as that defined in Section 7.1.3 is
followed.
To retrieve all pipe information bound to a DOTS client, the DOTS
client proceeds as specified in Section 7.1.1.
7.2.3. Deleting Installed DOTS Client Domain Pipe Capacity
A DELETE request is used to delete the specific information related
to an installed DOTS client domain pipe. The same procedure as that
defined in Section 7.1.4 is followed.
7.3. Telemetry Baseline
A DOTS client can communicate to its DOTS server(s) its normal
traffic baseline and connection capacity:
Total traffic normal baseline: Total traffic normal baseline data
provides the percentile values representing the total traffic
normal baseline. It can be represented for a target using 'total-
traffic-normal'.
The traffic normal per-protocol ('total-traffic-normal-per-
protocol') baseline is represented for a target and is transport-
protocol specific.
The traffic normal per-port-number ('total-traffic-normal-per-
port') baseline is represented for each port number bound to a
target.
If the DOTS client negotiated percentile values and units
(Section 7.1), these negotiated parameters will be used instead of
the default parameters. For each unit class used, the DOTS client
MUST auto-scale so that the appropriate unit is used.
Total connection capacity: If the target is susceptible to resource-
consuming DDoS attacks, the following optional attributes for the
target per transport protocol are useful for detecting resource-
consuming DDoS attacks:
* The maximum number of simultaneous connections that are allowed
to the target.
* The maximum number of simultaneous connections that are allowed
to the target per client.
* The maximum number of simultaneous embryonic connections that
are allowed to the target. The term "embryonic connection"
refers to a connection whose connection handshake is not
finished. Embryonic connections are only possible in
connection-oriented transport protocols like TCP or the Stream
Control Transmission Protocol (SCTP) [RFC9260].
* The maximum number of simultaneous embryonic connections that
are allowed to the target per client.
* The maximum number of connections allowed per second to the
target.
* The maximum number of connections allowed per second to the
target per client.
* The maximum number of requests (e.g., HTTP/DNS/SIP requests)
allowed per second to the target.
* The maximum number of requests allowed per second to the target
per client.
* The maximum number of outstanding partial requests allowed to
the target. Attacks relying upon partial requests create a
connection with a target but do not send a complete request
(e.g., an HTTP request).
* The maximum number of outstanding partial requests allowed to
the target per client.
The aggregate per transport protocol is captured in 'total-
connection-capacity', while port-specific capabilities are
represented using 'total-connection-capacity-per-port'.
Note that a target resource is identified using the attributes
'target-prefix', 'target-port-range', 'target-protocol', 'target-
fqdn', 'target-uri', or 'alias-name' as defined in Section 4.4.1.1 of
[RFC9132].
The tree structure of the normal traffic baseline is shown in
Figure 18.
structure dots-telemetry:
+-- (telemetry-message-type)?
+--:(telemetry-setup)
| ...
| +-- telemetry* []
| +-- (direction)?
| | +--:(server-to-client-only)
| | +-- tsid? uint32
| +-- (setup-type)?
| +--:(telemetry-config)
| | ...
| +--:(pipe)
| | ...
| +--:(baseline)
| +-- baseline* [id]
| +-- id uint32
| +-- target-prefix*
| | inet:ip-prefix
| +-- target-port-range* [lower-port]
| | +-- lower-port inet:port-number
| | +-- upper-port? inet:port-number
| +-- target-protocol* uint8
| +-- target-fqdn*
| | inet:domain-name
| +-- target-uri*
| | inet:uri
| +-- alias-name*
| | string
| +-- total-traffic-normal* [unit]
| | +-- unit unit
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| +-- total-traffic-normal-per-protocol*
| | [unit protocol]
| | +-- protocol uint8
| | +-- unit unit
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| +-- total-traffic-normal-per-port* [unit port]
| | +-- port inet:port-number
| | +-- unit unit
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| +-- total-connection-capacity* [protocol]
| | +-- protocol uint8
| | +-- connection? uint64
| | +-- connection-client? uint64
| | +-- embryonic? uint64
| | +-- embryonic-client? uint64
| | +-- connection-ps? uint64
| | +-- connection-client-ps? uint64
| | +-- request-ps? uint64
| | +-- request-client-ps? uint64
| | +-- partial-request-max? uint64
| | +-- partial-request-client-max? uint64
| +-- total-connection-capacity-per-port*
| [protocol port]
| +-- port
| | inet:port-number
| +-- protocol uint8
| +-- connection? uint64
| +-- connection-client? uint64
| +-- embryonic? uint64
| +-- embryonic-client? uint64
| +-- connection-ps? uint64
| +-- connection-client-ps? uint64
| +-- request-ps? uint64
| +-- request-client-ps? uint64
| +-- partial-request-max? uint64
| +-- partial-request-client-max? uint64
+--:(telemetry)
...
Figure 18: Telemetry Baseline Tree Structure
A DOTS client can share one or multiple normal traffic baselines
(e.g., aggregate or per-prefix baselines); each is uniquely
identified within the DOTS client domain with an identifier ('id').
This identifier can be used to update a baseline entry, delete a
specific entry, etc.
7.3.1. Conveying DOTS Client Domain Baseline Information
Considerations similar to those specified in Section 7.1.2 are
followed, with one exception:
* The relative order of two PUT requests carrying DOTS client domain
baseline attributes from a DOTS client is determined by comparing
their respective 'tsid' values. If these two requests have
overlapping targets, the PUT request with a higher numeric 'tsid'
value will override the request with a lower numeric 'tsid' value.
The overlapped lower numeric 'tsid' MUST be automatically deleted
and no longer be available.
Two PUT requests from a DOTS client have overlapping targets if there
is a common IP address, IP prefix, FQDN, URI, or alias name. Also,
two PUT requests from a DOTS client have overlapping targets from the
perspective of the DOTS server if the addresses associated with the
FQDN, URI, or alias are overlapping with each other or with 'target-
prefix'.
DOTS clients SHOULD minimize the number of active 'tsid's used for
baseline information. In order to avoid maintaining a long list of
'tsid's for baseline information, it is RECOMMENDED that DOTS clients
include in any request to update information related to a given
target the information regarding other targets (already communicated
using a lower 'tsid' value) (assuming that this information fits
within one single datagram). This update request will override these
existing requests and hence optimize the number of 'tsid' requests
per DOTS client.
If no target attribute is included in the request, this is an
indication that the baseline information applies for the DOTS client
domain as a whole.
An example of a PUT request to convey the baseline information is
shown in Figure 19.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=129"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"baseline": [
{
"id": 1,
"target-prefix": [
"2001:db8:6401::1/128",
"2001:db8:6401::2/128"
],
"total-traffic-normal": [
{
"unit": "megabit-ps",
"peak-g": "60"
}
]
}
]
}
]
}
}
Figure 19: PUT to Convey DOTS Traffic Baseline Information,
Depicted as per Section 5.6
The DOTS client may share protocol-specific baseline information
(e.g., TCP and UDP) as shown in Figure 20.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tsid=130"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry-setup": {
"telemetry": [
{
"baseline": [
{
"id": 1,
"target-prefix": [
"2001:db8:6401::1/128",
"2001:db8:6401::2/128"
],
"total-traffic-normal-per-protocol": [
{
"unit": "megabit-ps",
"protocol": 6,
"peak-g": "50"
},
{
"unit": "megabit-ps",
"protocol": 17,
"peak-g": "10"
}
]
}
]
}
]
}
}
Figure 20: PUT to Convey DOTS Traffic Baseline Information (2),
Depicted as per Section 5.6
The normal traffic baseline information should be updated to reflect
legitimate overloads (e.g., flash crowds) to prevent unnecessary
mitigation.
7.3.2. Retrieving Installed Normal Traffic Baseline Information
A GET request with a 'tsid' Uri-Path parameter is used to retrieve a
specific installed DOTS client domain's baseline traffic information.
The same procedure as that defined in Section 7.1.3 is followed.
To retrieve all baseline information bound to a DOTS client, the DOTS
client proceeds as specified in Section 7.1.1.
7.3.3. Deleting Installed Normal Traffic Baseline Information
A DELETE request is used to delete the installed DOTS client domain's
normal traffic baseline information. The same procedure as that
defined in Section 7.1.4 is followed.
7.4. Resetting the Installed Telemetry Setup
Upon bootstrapping (or reboot or any other event that may alter the
DOTS client setup), a DOTS client MAY send a DELETE request to set
the telemetry parameters to default values. Such a request does not
include any 'tsid' parameters. An example of such a request is
depicted in Figure 21.
Header: DELETE (Code=0.04)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm-setup"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Figure 21: Deleting the Telemetry Configuration
7.5. Conflict with Other DOTS Clients of the Same Domain
A DOTS server may detect conflicts between requests conveying pipe
and baseline information received from DOTS clients of the same DOTS
client domain. 'conflict-information' is used to report the conflict
to the DOTS client, following guidelines for conflict handling
similar to those discussed in Section 4.4.1 of [RFC9132]. The
conflict cause can be set to one of these values:
1: Overlapping targets (Section 4.4.1 of [RFC9132]).
5: Overlapping pipe scope (see Section 13).
8. DOTS Pre-or-Ongoing-Mitigation Telemetry
There are two broad types of DDoS attacks: bandwidth-consuming
attacks and target-resource-consuming attacks. This section outlines
the set of DOTS telemetry attributes (Section 8.1) that covers both
types of attacks. The objective of these attributes is to allow for
the complete knowledge of attacks and the various particulars that
can best characterize attacks.
The "ietf-dots-telemetry" YANG module (Section 11.1) defines the data
structure of a new message type called 'telemetry'. The tree
structure of the 'telemetry' message type is shown in Figure 22.
structure dots-telemetry:
+-- (telemetry-message-type)?
+--:(telemetry-setup)
| ...
| +-- telemetry* []
| +-- (direction)?
| | +--:(server-to-client-only)
| | +-- tsid? uint32
| +-- (setup-type)?
| +--:(telemetry-config)
| | ...
| +--:(pipe)
| | ...
| +--:(baseline)
| ...
+--:(telemetry)
+-- pre-or-ongoing-mitigation* []
+-- (direction)?
| +--:(server-to-client-only)
| +-- tmid? uint32
+-- target
| ...
+-- total-traffic* [unit]
| ...
+-- total-traffic-protocol* [unit protocol]
| ...
+-- total-traffic-port* [unit port]
| ...
+-- total-attack-traffic* [unit]
| ...
+-- total-attack-traffic-protocol* [unit protocol]
| ...
+-- total-attack-traffic-port* [unit port]
| ...
+-- total-attack-connection-protocol* [protocol]
| ...
+-- total-attack-connection-port* [protocol port]
| ...
+-- attack-detail* [vendor-id attack-id]
...
Figure 22: Telemetry Message Type Tree Structure
The pre-or-ongoing-mitigation telemetry attributes are indicated by
the path suffix '/tm'. '/tm' is appended to the path prefix to form
the URI used with a CoAP request to signal the DOTS telemetry. Pre-
or-ongoing-mitigation telemetry attributes as specified in
Section 8.1 can be signaled between DOTS agents.
Pre-or-ongoing-mitigation telemetry attributes may be sent by a DOTS
client or a DOTS server.
DOTS agents SHOULD bind pre-or-ongoing-mitigation telemetry data to
mitigation requests associated with the resources under attack. In
particular, a telemetry PUT request sent after a mitigation request
may include a reference to that mitigation request ('mid-list') as
shown in Figure 23. An example illustrating request correlation by
means of 'target-prefix' is shown in Figure 24.
Much of the pre-or-ongoing-mitigation telemetry data uses a unit that
falls under the unit class that is configured following the procedure
described in Section 7.1.2. When generating telemetry data to send
to a peer, the DOTS agent MUST auto-scale so that one or more
appropriate units are used.
+-----------+ +-----------+
|DOTS client| |DOTS server|
+-----------+ +-----------+
| |
|==============Mitigation Request (mid)==============>|
| |
|==============Telemetry (mid-list{mid})=============>|
| |
Figure 23: Example of Request Correlation Using 'mid'
+-----------+ +-----------+
|DOTS client| |DOTS server|
+-----------+ +-----------+
| |
|<===============Telemetry (target-prefix)============|
| |
|========Mitigation Request (target-prefix)==========>|
| |
Figure 24: Example of Request Correlation Using 'target-prefix'
DOTS agents MUST NOT send pre-or-ongoing-mitigation telemetry
notifications to the same peer more frequently than once every
'telemetry-notify-interval' (Section 7.1). If a telemetry
notification is sent using a block-like transfer mechanism (e.g.,
[RFC9177]), this rate-limit policy MUST NOT consider these individual
blocks as separate notifications, but as a single notification.
DOTS pre-or-ongoing-mitigation telemetry request and response
messages MUST be marked as Non-confirmable messages (Section 2.1 of
[RFC7252]).
8.1. Pre-or-Ongoing-Mitigation DOTS Telemetry Attributes
Section 3 discusses the motivation for using the DOTS telemetry
attributes. These attributes are specified in the following
subsections.
8.1.1. Target
A target resource (Figure 25) is identified using the attributes
'target-prefix', 'target-port-range', 'target-protocol', 'target-
fqdn', 'target-uri', 'alias-name', or a pointer to a mitigation
request ('mid-list').
+--:(telemetry)
+-- pre-or-ongoing-mitigation* []
+-- (direction)?
| +--:(server-to-client-only)
| +-- tmid? uint32
+-- target
| +-- target-prefix* inet:ip-prefix
| +-- target-port-range* [lower-port]
| | +-- lower-port inet:port-number
| | +-- upper-port? inet:port-number
| +-- target-protocol* uint8
| +-- target-fqdn* inet:domain-name
| +-- target-uri* inet:uri
| +-- alias-name* string
| +-- mid-list* uint32
+-- total-traffic* [unit]
| ...
+-- total-traffic-protocol* [unit protocol]
| ...
+-- total-traffic-port* [unit port]
| ...
+-- total-attack-traffic* [unit]
| ...
+-- total-attack-traffic-protocol* [unit protocol]
| ...
+-- total-attack-traffic-port* [unit port]
| ...
+-- total-attack-connection-protocol* [protocol]
| ...
+-- total-attack-connection-port* [protocol port]
| ...
+-- attack-detail* [vendor-id attack-id]
...
Figure 25: Target Tree Structure
At least one of the attributes 'target-prefix', 'target-fqdn',
'target-uri', 'alias-name', or 'mid-list' MUST be present in the
target definition.
If the target is susceptible to bandwidth-consuming attacks, the
attributes representing the percentile values of the 'attack-id'
attack traffic are included.
If the target is susceptible to resource-consuming DDoS attacks, the
attributes defined in Section 8.1.4 are applicable for representing
the attack.
At least the 'target' attribute and one other pre-or-ongoing-
mitigation attribute MUST be present in the DOTS telemetry message.
8.1.2. Total Traffic
The 'total-traffic' attribute (Figure 26) conveys the percentile
values (including peak and current observed values) of the total
observed traffic. More fine-grained information about the total
traffic can be conveyed in the 'total-traffic-protocol' and 'total-
traffic-port' attributes.
The 'total-traffic-protocol' attribute represents the total traffic
for a target and is transport-protocol specific.
The 'total-traffic-port' attribute represents the total traffic for a
target per port number.
+--:(telemetry)
+-- pre-or-ongoing-mitigation* []
+-- (direction)?
| +--:(server-to-client-only)
| +-- tmid? uint32
+-- target
| ...
+-- total-traffic* [unit]
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-traffic-protocol* [unit protocol]
| +-- protocol uint8
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-traffic-port* [unit port]
| +-- port inet:port-number
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-traffic* [unit]
| ...
+-- total-attack-traffic-protocol* [unit protocol]
| ...
+-- total-attack-traffic-port* [unit port]
| ...
+-- total-attack-connection-protocol* [protocol]
| ...
+-- total-attack-connection-port* [protocol port]
| ...
+-- attack-detail* [vendor-id attack-id]
...
Figure 26: Total Traffic Tree Structure
8.1.3. Total Attack Traffic
The 'total-attack-traffic' attribute (Figure 27) conveys the total
observed attack traffic. More fine-grained information about the
total attack traffic can be conveyed in the 'total-attack-traffic-
protocol' and 'total-attack-traffic-port' attributes.
The 'total-attack-traffic-protocol' attribute represents the total
attack traffic for a target and is transport-protocol specific.
The 'total-attack-traffic-port' attribute represents the total attack
traffic for a target per port number.
+--:(telemetry)
+-- pre-or-ongoing-mitigation* []
+-- (direction)?
| +--:(server-to-client-only)
| +-- tmid? uint32
+-- target
| ...
+-- total-traffic* [unit]
| ...
+-- total-traffic-protocol* [unit protocol]
| ...
+-- total-traffic-port* [unit port]
| ...
+-- total-attack-traffic* [unit]
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-traffic-protocol* [unit protocol]
| +-- protocol uint8
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-traffic-port* [unit port]
| +-- port inet:port-number
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-connection-protocol* [protocol]
| ...
+-- total-attack-connection-port* [protocol port]
| ...
+-- attack-detail* [vendor-id attack-id]
...
Figure 27: Total Attack Traffic Tree Structure
8.1.4. Total Attack Connections
If the target is susceptible to resource-consuming DDoS attacks, the
'total-attack-connection-protocol' attribute is used to convey the
percentile values (including peak and current observed values) of
various attributes related to the total attack connections. The
following optional sub-attributes for the target per transport
protocol are included to represent the attack characteristics:
* The number of simultaneous attack connections to the target.
* The number of simultaneous embryonic connections to the target.
* The number of attack connections per second to the target.
* The number of attack requests per second to the target.
* The number of attack partial requests to the target.
The total attack connections per port number are represented using
the 'total-attack-connection-port' attribute.
+--:(telemetry)
+-- pre-or-ongoing-mitigation* []
+-- (direction)?
| +--:(server-to-client-only)
| +-- tmid? uint32
+-- target
| ...
+-- total-traffic* [unit]
| ...
+-- total-traffic-protocol* [unit protocol]
| ...
+-- total-traffic-port* [unit port]
| ...
+-- total-attack-traffic* [unit]
| ...
+-- total-attack-traffic-protocol* [unit protocol]
| ...
+-- total-attack-traffic-port* [unit port]
| ...
+-- total-attack-connection-protocol* [protocol]
| +-- protocol uint8
| +-- connection-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- embryonic-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- connection-ps-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- request-ps-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- partial-request-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-connection-port* [protocol port]
| +-- protocol uint8
| +-- port inet:port-number
| +-- connection-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- embryonic-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- connection-ps-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- request-ps-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- partial-request-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- attack-detail* [vendor-id attack-id]
...
Figure 28: Total Attack Connections Tree Structure
8.1.5. Attack Details
This attribute (depicted in Figure 29) is used to signal a set of
details characterizing an attack. The following sub-attributes
describing the ongoing attack can be signaled as attack details:
vendor-id: Vendor ID. This parameter represents a security vendor's
enterprise number as registered in the IANA "Private Enterprise
Numbers" registry [Private-Enterprise-Numbers].
attack-id: Unique identifier assigned for the attack by a vendor.
This parameter MUST be present, independently of whether 'attack-
description' is included or not.
description-lang: Indicates the language tag that is used for the
text that is included in the 'attack-description' attribute. This
attribute is encoded following the rules in Section 2.1 of
[RFC5646]. The default language tag is "en-US".
attack-description: Textual representation of the attack
description. This description is related to the class of attack
rather than a specific instance of it. Natural Language
Processing techniques (e.g., word embedding) might provide some
utility in mapping the attack description to an attack type.
Textual representation of an attack solves two problems: it avoids
the need to (a) create mapping tables manually between vendors and
(b) standardize attack types that keep evolving.
attack-severity: Attack severity level. This attribute takes one of
the values defined in Section 3.12.2 of [RFC7970].
start-time: The time the attack started. The attack's start time is
expressed in seconds relative to 1970-01-01T00:00Z (Section 3.4.2
of [RFC8949]). The CBOR encoding is modified so that the leading
tag 1 (epoch-based date/time) MUST be omitted.
end-time: The time the attack ended. The attack's end time is
expressed in seconds relative to 1970-01-01T00:00Z (Section 3.4.2
of [RFC8949]). The CBOR encoding is modified so that the leading
tag 1 (epoch-based date/time) MUST be omitted.
source-count: A count of sources involved in the attack targeting
the victim.
top-talker: A list of attack sources that are involved in an attack
and that are generating an important part of the attack traffic.
The top talkers are represented using 'source-prefix'.
'spoofed-status' indicates whether a top talker is a spoofed IP
address (e.g., reflection attacks) or not. If no 'spoofed-status'
data node is included, this means that the spoofing status is
unknown.
If the target is being subjected to a bandwidth-consuming attack,
a statistical profile of the attack traffic from each of the top
talkers is included ('total-attack-traffic'; see Section 8.1.3).
If the target is being subjected to a resource-consuming DDoS
attack, the same attributes as those defined in Section 8.1.4 are
applicable for characterizing the attack on a per-talker basis.
+--:(telemetry)
+-- pre-or-ongoing-mitigation* []
+-- (direction)?
| +--:(server-to-client-only)
| +-- tmid? uint32
+-- target
| ...
+-- total-traffic* [unit]
| ...
+-- total-traffic-protocol* [unit protocol]
| ...
+-- total-traffic-port* [unit port]
| ...
+-- total-attack-traffic* [unit]
| ...
+-- total-attack-traffic-protocol* [unit protocol]
| ...
+-- total-attack-traffic-port* [unit port]
| ...
+-- total-attack-connection-protocol* [protocol]
| ...
+-- total-attack-connection-port* [protocol port]
| ...
+-- attack-detail* [vendor-id attack-id]
+-- vendor-id uint32
+-- attack-id uint32
+-- description-lang? string
+-- attack-description? string
+-- attack-severity? attack-severity
+-- start-time? uint64
+-- end-time? uint64
+-- source-count
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- top-talker
+-- talker* [source-prefix]
+-- spoofed-status? boolean
+-- source-prefix inet:ip-prefix
+-- source-port-range* [lower-port]
| +-- lower-port inet:port-number
| +-- upper-port? inet:port-number
+-- source-icmp-type-range* [lower-type]
| +-- lower-type uint8
| +-- upper-type? uint8
+-- total-attack-traffic* [unit]
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-connection-protocol*
[protocol]
+-- protocol uint8
+-- connection-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- embryonic-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- connection-ps-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- request-ps-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- partial-request-c
+-- low-percentile-g? yang:gauge64
+-- mid-percentile-g? yang:gauge64
+-- high-percentile-g? yang:gauge64
+-- peak-g? yang:gauge64
+-- current-g? yang:gauge64
Figure 29: Attack Details Tree Structure
In order to optimize the size of telemetry data conveyed over the
DOTS signal channel, DOTS agents MAY use the DOTS data channel
[RFC8783] to exchange vendor-specific attack mapping details (that
is, {vendor identifier, attack identifier} ==> textual representation
of the attack description). As such, DOTS agents do not have to
convey an attack description systematically in their telemetry
messages over the DOTS signal channel. Refer to Section 8.1.6.
8.1.6. Vendor Attack Mapping
Multiple mappings for different vendor identifiers may be used; the
DOTS agent transmitting telemetry information can elect to use one or
more vendor mappings even in the same telemetry message.
| Note: It is possible that a DOTS server is making use of
| multiple DOTS mitigators, each from a different vendor. How
| telemetry information and vendor mappings are exchanged between
| DOTS servers and DOTS mitigators is outside the scope of this
| document.
DOTS clients and servers may be provided with mappings from different
vendors and so have their own different sets of vendor attack
mappings. A DOTS agent MUST accept receipt of telemetry data with a
vendor identifier that is different than the identifier it uses to
transmit telemetry data. Furthermore, it is possible that the DOTS
client and DOTS server are provided by the same vendor but the vendor
mapping tables are at different revisions. The DOTS client SHOULD
transmit telemetry information using any vendor mapping(s) that it
provided to the DOTS server (e.g., using a POST as depicted in
Figure 30), and the DOTS server SHOULD use any vendor mappings(s)
provided to the DOTS client when transmitting telemetry data to the
peer DOTS agent.
POST /restconf/data/ietf-dots-data-channel:dots-data\
/dots-client=dz6pHjaADkaFTbjr0JGBpw HTTP/1.1
Host: example.com
Content-Type: application/yang-data+json
{
"ietf-dots-mapping:vendor-mapping": {
"vendor": [
{
"vendor-id": 345,
"vendor-name": "mitigator-c",
"last-updated": "1629898958",
"attack-mapping": [
{
"attack-id": 1,
"attack-description":
"Include a description of this attack"
},
{
"attack-id": 2,
"attack-description":
"Again, include a description of the attack"
}
]
}
]
}
}
Figure 30: POST to Install Vendor Attack Mapping Details
The "ietf-dots-mapping" YANG module defined in Section 11.2 augments
the "ietf-dots-data-channel" module [RFC8783]. The tree structure of
the "ietf-dots-mapping" module is shown in Figure 31.
module: ietf-dots-mapping
augment /data-channel:dots-data/data-channel:dots-client:
+--rw vendor-mapping {dots-telemetry}?
+--rw vendor* [vendor-id]
+--rw vendor-id uint32
+--rw vendor-name? string
+--rw description-lang? string
+--rw last-updated uint64
+--rw attack-mapping* [attack-id]
+--rw attack-id uint32
+--rw attack-description string
augment /data-channel:dots-data/data-channel:capabilities:
+--ro vendor-mapping-enabled? boolean {dots-telemetry}?
augment /data-channel:dots-data:
+--ro vendor-mapping {dots-telemetry}?
+--ro vendor* [vendor-id]
+--ro vendor-id uint32
+--ro vendor-name? string
+--ro description-lang? string
+--ro last-updated uint64
+--ro attack-mapping* [attack-id]
+--ro attack-id uint32
+--ro attack-description string
Figure 31: Vendor Attack Mapping Tree Structure
A DOTS client sends a GET request over the DOTS data channel to
retrieve the capabilities supported by a DOTS server as per
Section 7.1 of [RFC8783]. This request is meant to assess whether
the capability of sharing vendor attack mapping details is supported
by the server (i.e., check the value of 'vendor-mapping-enabled').
If 'vendor-mapping-enabled' is set to 'true', a DOTS client MAY send
a GET request to retrieve the DOTS server's vendor attack mapping
details. An example of such a GET request is shown in Figure 32.
GET /restconf/data/ietf-dots-data-channel:dots-data\
/ietf-dots-mapping:vendor-mapping HTTP/1.1
Host: example.com
Accept: application/yang-data+json
Figure 32: GET to Retrieve the Vendor Attack Mappings of a DOTS
Server
A DOTS client can retrieve only the list of vendors supported by the
DOTS server. It does so by setting the "depth" parameter
(Section 4.8.2 of [RFC8040]) to "3" in the GET request as shown in
Figure 33. An example of a response body received from the DOTS
server as a response to such a request is illustrated in Figure 34.
GET /restconf/data/ietf-dots-data-channel:dots-data\
/ietf-dots-mapping:vendor-mapping?depth=3 HTTP/1.1
Host: example.com
Accept: application/yang-data+json
Figure 33: GET to Retrieve the Vendors List Used by a DOTS Server
{
"ietf-dots-mapping:vendor-mapping": {
"vendor": [
{
"vendor-id": 32473,
"vendor-name": "mitigator-s",
"last-updated": "1629898758",
"attack-mapping": []
}
]
}
}
Figure 34: Response Message Body to a GET to Retrieve the Vendors
List Used by a DOTS Server
The DOTS client repeats the above procedure regularly (e.g., once a
week) to update the DOTS server's vendor attack mapping details.
If the DOTS client concludes that the DOTS server does not have any
reference to the specific vendor attack mapping details, the DOTS
client uses a POST request to install its vendor attack mapping
details. An example of such a POST request is depicted in Figure 30.
The DOTS server indicates the result of processing the POST request
using the status-line. A "201 Created" status-line MUST be returned
in the response if the DOTS server has accepted the vendor attack
mapping details. If the request is missing a mandatory attribute or
contains an invalid or unknown parameter, a "400 Bad Request" status-
line MUST be returned by the DOTS server in the response. The error-
tag is set to "missing-attribute", "invalid-value", or "unknown-
element" as a function of the encountered error.
If the request is received via a server-domain DOTS gateway but the
DOTS server does not maintain a 'cdid' for this 'cuid' while a 'cdid'
is expected to be supplied, the DOTS server MUST reply with a "403
Forbidden" status-line and the error-tag "access-denied". Upon
receipt of this message, the DOTS client MUST register (Section 5.1
of [RFC8783]).
The DOTS client uses the PUT request to modify its vendor attack
mapping details maintained by the DOTS server (e.g., add a new
mapping entry, update an existing mapping).
A DOTS client uses a GET request to retrieve its vendor attack
mapping details as maintained by the DOTS server (Figure 35).
GET /restconf/data/ietf-dots-data-channel:dots-data\
/dots-client=dz6pHjaADkaFTbjr0JGBpw\
/ietf-dots-mapping:vendor-mapping?\
content=all HTTP/1.1
Host: example.com
Accept: application/yang-data+json
Figure 35: GET to Retrieve Installed Vendor Attack Mapping Details
When conveying attack details in DOTS telemetry messages
(Sections 8.2, 8.3, and 9), DOTS agents MUST NOT include the 'attack-
description' attribute unless the corresponding attack mapping
details were not previously shared with the peer DOTS agent.
8.2. From DOTS Clients to DOTS Servers
DOTS clients use PUT requests to signal pre-or-ongoing-mitigation
telemetry to DOTS servers. An example of such a request is shown in
Figure 36.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tmid=123"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry": {
"pre-or-ongoing-mitigation": [
{
"target": {
"target-prefix": [
"2001:db8::1/128"
]
},
"total-attack-traffic-protocol": [
{
"protocol": 17,
"unit": "megabit-ps",
"mid-percentile-g": "900"
}
],
"attack-detail": [
{
"vendor-id": 32473,
"attack-id": 77,
"start-time": "1608336568",
"attack-severity": "high"
}
]
}
]
}
}
Figure 36: PUT to Send Pre-or-Ongoing-Mitigation Telemetry,
Depicted as per Section 5.6
'cuid' is a mandatory Uri-Path parameter for DOTS PUT requests.
The following additional Uri-Path parameter is defined:
tmid: The Telemetry Identifier is an identifier for the DOTS pre-or-
ongoing-mitigation telemetry data represented as an integer. This
identifier MUST be generated by DOTS clients. 'tmid' values MUST
increase monotonically whenever a DOTS client needs to convey a
new set of pre-or-ongoing-mitigation telemetry data.
The procedure specified in Section 4.4.1 of [RFC9132] for 'mid'
rollover MUST be followed for 'tmid' rollover.
This is a mandatory attribute. 'tmid' MUST appear after 'cuid' in
the Uri-Path options.
'cuid' and 'tmid' MUST NOT appear in the PUT request message body.
At least the 'target' attribute and another pre-or-ongoing-mitigation
attribute (Section 8.1) MUST be present in the PUT request. If only
the 'target' attribute is present, this request is handled as per
Section 8.3.
The relative order of two PUT requests carrying DOTS pre-or-ongoing-
mitigation telemetry from a DOTS client is determined by comparing
their respective 'tmid' values. If these two requests have an
overlapping 'target', the PUT request with a higher numeric 'tmid'
value will override the request with a lower numeric 'tmid' value.
The overlapped lower numeric 'tmid' MUST be automatically deleted and
no longer be available.
The DOTS server indicates the result of processing a PUT request
using CoAP Response Codes. In particular, the 2.04 (Changed)
Response Code is returned if the DOTS server has accepted the pre-or-
ongoing-mitigation telemetry. The 5.03 (Service Unavailable)
Response Code is returned if the DOTS server has erred. The 5.03
Response Code uses the Max-Age Option to indicate the number of
seconds after which to retry.
How long a DOTS server maintains a 'tmid' as active or logs the
enclosed telemetry information is implementation specific. Note that
if a 'tmid' is still active, then logging details are updated by the
DOTS server as a function of the updates received from the peer DOTS
client.
A DOTS client that lost the state of its active 'tmid's or has to set
'tmid' back to zero (e.g., crash or restart) MUST send a GET request
to the DOTS server to retrieve the list of active 'tmid' values. The
DOTS client may then delete 'tmid's that should not be active anymore
(Figure 37). Sending a DELETE with no 'tmid' indicates that all
'tmid's must be deactivated (Figure 38).
Header: DELETE (Code=0.04)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tmid=123"
Figure 37: Deleting Specific Pre-or-Ongoing-Mitigation Telemetry
Information
Header: DELETE (Code=0.04)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Figure 38: Deleting All Pre-or-Ongoing-Mitigation Telemetry
Information
8.3. From DOTS Servers to DOTS Clients
The pre-or-ongoing-mitigation data (attack details in particular) can
also be signaled from DOTS servers to DOTS clients. For example, a
DOTS server co-located with a DDoS detector can collect monitoring
information from the target network, identify a DDoS attack using
statistical analysis or deep learning techniques, and signal the
attack details to the DOTS client.
The DOTS client can use the attack details to decide whether to
trigger a DOTS mitigation request or not. Furthermore, the security
operations personnel at the DOTS client domain can use the attack
details to determine the protection strategy and select the
appropriate DOTS server for mitigating the attack.
In order to receive pre-or-ongoing-mitigation telemetry notifications
from a DOTS server, a DOTS client MUST send a PUT (followed by a GET)
with the target filter. An example of such a PUT request is shown in
Figure 39. In order to avoid maintaining a long list of such
requests, it is RECOMMENDED that DOTS clients include all targets in
the same request (assuming that this information fits within one
single datagram). DOTS servers may be instructed to restrict the
number of pre-or-ongoing-mitigation requests per DOTS client domain.
The pre-or-ongoing-mitigation requests MUST be maintained in an
active state by the DOTS server until a DELETE request is received
from the same DOTS client to clear this pre-or-ongoing-mitigation
telemetry or when the DOTS client is considered inactive (e.g.,
Section 3.5 of [RFC8783]).
The relative order of two PUT requests carrying DOTS pre-or-ongoing-
mitigation telemetry from a DOTS client is determined by comparing
their respective 'tmid' values. If these two requests have an
overlapping 'target', the PUT request with a higher numeric 'tmid'
value will override the request with a lower numeric 'tmid' value.
The overlapped lower numeric 'tmid' MUST be automatically deleted and
no longer be available.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tmid=567"
Content-Format: "application/dots+cbor"
{
"ietf-dots-telemetry:telemetry": {
"pre-or-ongoing-mitigation": [
{
"target": {
"target-prefix": [
"2001:db8::/32"
]
}
}
]
}
}
Figure 39: PUT to Request Pre-or-Ongoing-Mitigation Telemetry,
Depicted as per Section 5.6
DOTS clients of the same domain can ask to receive pre-or-ongoing-
mitigation telemetry bound to the same target without being
considered to be "overlapping" and in conflict.
Once the PUT request to instantiate request state on the server has
succeeded, the DOTS client issues a GET request to receive ongoing
telemetry updates. The client uses the Observe Option, set to "0"
(register), in the GET request to receive asynchronous notifications
carrying pre-or-ongoing-mitigation telemetry data from the DOTS
server. The GET request can specify a specific 'tmid' (Figure 40) or
omit the 'tmid' (Figure 41) to receive updates on all active requests
from that client.
Header: GET (Code=0.01)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "tmid=567"
Observe: 0
Figure 40: GET to Subscribe to Telemetry Asynchronous
Notifications for a Specific 'tmid'
Header: GET (Code=0.01)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Observe: 0
Figure 41: GET to Subscribe to Telemetry Asynchronous
Notifications for All 'tmid's
The DOTS client can use a filter to request a subset of the
asynchronous notifications from the DOTS server by indicating one or
more Uri-Query options in its GET request. A Uri-Query option can
include the following parameters to restrict the notifications based
on the attack target: 'target-prefix', 'target-port', 'target-
protocol', 'target-fqdn', 'target-uri', 'alias-name', 'mid', and 'c'
(content) (Section 5.4). Furthermore:
* If more than one Uri-Query option is included in a request, these
options are interpreted in the same way as when multiple target
attributes are included in a message body (Section 4.4.1 of
[RFC9132]).
* If multiple values of a query parameter are to be included in a
request, these values MUST be included in the same Uri-Query
option and separated by a "," character without any spaces.
* Range values (i.e., a contiguous inclusive block) can be included
for the 'target-port', 'target-protocol', and 'mid' parameters by
indicating the two boundary values separated by a "-" character.
* Wildcard names (i.e., a name with the leftmost label is the "*"
character) can be included in 'target-fqdn' or 'target-uri'
parameters. DOTS clients MUST NOT include a name in which the "*"
character is included in a label other than the leftmost label.
"*.example.com" is an example of a valid wildcard name that can be
included as a value of the 'target-fqdn' parameter in a Uri-Query
option.
DOTS clients may also filter out the asynchronous notifications from
the DOTS server by indicating information about a specific attack
source. To that aim, a DOTS client may include 'source-prefix',
'source-port', or 'source-icmp-type' in a Uri-Query option. The same
considerations (ranges, multiple values) specified for target
attributes apply for source attributes. Special care SHOULD be taken
when using these filters, as their use may cause some attacks to be
hidden from the requesting DOTS client (e.g., if the attack changes
its source information).
Requests with invalid query types (e.g., not supported, malformed)
received by the DOTS server MUST be rejected with a 4.00 (Bad
Request) Response Code.
An example of a request to subscribe to asynchronous telemetry
notifications regarding UDP traffic is shown in Figure 42. This
filter will be applied for all 'tmid's.
Header: GET (Code=0.01)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "tm"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Query: "target-protocol=17"
Observe: 0
Figure 42: GET Request to Receive Telemetry Asynchronous
Notifications Filtered Using Uri-Query
The DOTS server will send asynchronous notifications to the DOTS
client when an attack event is detected, following considerations
similar to those discussed in Section 4.4.2.1 of [RFC9132]. An
example of a pre-or-ongoing-mitigation telemetry notification is
shown in Figure 43.
{
"ietf-dots-telemetry:telemetry": {
"pre-or-ongoing-mitigation": [
{
"tmid": 567,
"target": {
"target-prefix": [
"2001:db8::1/128"
]
},
"target-protocol": [
17
],
"total-attack-traffic": [
{
"unit": "megabit-ps",
"mid-percentile-g": "900"
}
],
"attack-detail": [
{
"vendor-id": 32473,
"attack-id": 77,
"start-time": "1618339785",
"attack-severity": "high"
}
]
}
]
}
}
Figure 43: Message Body of a Pre-or-Ongoing-Mitigation Telemetry
Notification from the DOTS Server, Depicted as per Section 5.6
A DOTS server sends the aggregate data for a target using the 'total-
attack-traffic' attribute. The aggregate assumes that Uri-Query
filters are applied on the target. The DOTS server MAY include more
fine-grained data when needed (that is, 'total-attack-traffic-
protocol' and 'total-attack-traffic-port'). If a port filter (or
protocol filter) is included in a request, 'total-attack-traffic-
protocol' (or 'total-attack-traffic-port') conveys the data with the
port (or protocol) filter applied.
A DOTS server may aggregate pre-or-ongoing-mitigation data (e.g.,
'top-talker') for all targets of a domain or, when justified, send
specific information (e.g., 'top-talker') for a specific target.
The DOTS client may log pre-or-ongoing-mitigation telemetry data with
an alert sent to an administrator or a network controller. The DOTS
client may send a mitigation request if the attack cannot be handled
locally.
A DOTS client that is not interested in receiving pre-or-ongoing-
mitigation telemetry data for a target sends a DELETE request similar
to the DELETE request depicted in Figure 37.
9. DOTS Telemetry Mitigation Status Update
9.1. From DOTS Clients to DOTS Servers: Mitigation Efficacy DOTS
Telemetry Attributes
The mitigation efficacy telemetry attributes can be signaled from
DOTS clients to DOTS servers as part of the periodic mitigation
efficacy updates to the server (Section 4.4.3 of [RFC9132]).
Total attack traffic: The overall attack traffic as observed from
the DOTS client's perspective during an active mitigation. See
Figure 27.
Attack details: The overall attack details as observed from the DOTS
client's perspective during an active mitigation. See
Section 8.1.5.
The "ietf-dots-telemetry" YANG module (Section 11.1) augments the
'mitigation-scope' message type defined in the "ietf-dots-signal-
channel" module [RFC9132] so that these attributes can be signaled by
a DOTS client in a mitigation efficacy update (Figure 44).
augment-structure /dots-signal:dots-signal/dots-signal:message-type
/dots-signal:mitigation-scope/dots-signal:scope:
+-- total-attack-traffic* [unit]
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- attack-detail* [vendor-id attack-id]
+-- vendor-id uint32
+-- attack-id uint32
+-- attack-description? string
+-- attack-severity? attack-severity
+-- start-time? uint64
+-- end-time? uint64
+-- source-count
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- top-talker
+-- talker* [source-prefix]
+-- spoofed-status? boolean
+-- source-prefix inet:ip-prefix
+-- source-port-range* [lower-port]
| +-- lower-port inet:port-number
| +-- upper-port? inet:port-number
+-- source-icmp-type-range* [lower-type]
| +-- lower-type uint8
| +-- upper-type? uint8
+-- total-attack-traffic* [unit]
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-connection
+-- connection-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- embryonic-c
| ...
+-- connection-ps-c
| ...
+-- request-ps-c
| ...
+-- partial-request-c
...
Figure 44: Telemetry Efficacy Update Tree Structure
In order to signal telemetry data in a mitigation efficacy update, it
is RECOMMENDED that the DOTS client have already established a DOTS
telemetry setup session with the server in 'idle' time. Such a
session is primarily meant to assess whether the peer DOTS server
supports telemetry extensions and to thus prevent message processing
failure (Section 3.1 of [RFC9132]).
An example of an efficacy update with telemetry attributes is
depicted in Figure 45.
Header: PUT (Code=0.03)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "mitigate"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "mid=123"
If-Match:
Content-Format: "application/dots+cbor"
{
"ietf-dots-signal-channel:mitigation-scope": {
"scope": [
{
"alias-name": [
"https1",
"https2"
],
"attack-status": "under-attack",
"ietf-dots-telemetry:total-attack-traffic": [
{
"unit": "megabit-ps",
"mid-percentile-g": "900"
}
]
}
]
}
}
Figure 45: Example of Mitigation Efficacy Update with Telemetry
Attributes, Depicted as per Section 5.6
9.2. From DOTS Servers to DOTS Clients: Mitigation Status DOTS
Telemetry Attributes
The mitigation status telemetry attributes can be signaled from the
DOTS server to the DOTS client as part of the periodic mitigation
status update (Section 4.4.2 of [RFC9132]). In particular, DOTS
clients can receive asynchronous notifications of the attack details
from DOTS servers using the Observe Option defined in [RFC7641].
In order to make use of this feature, DOTS clients MUST establish a
telemetry session with the DOTS server in 'idle' time and MUST set
the 'server-originated-telemetry' attribute to 'true'.
DOTS servers MUST NOT include telemetry attributes in mitigation
status updates sent to DOTS clients for telemetry sessions in which
the 'server-originated-telemetry' attribute is set to 'false'.
As defined in [RFC8612], the actual mitigation activities can include
several countermeasure mechanisms. The DOTS server signals the
current operational status of relevant countermeasures. A list of
attacks detected by these countermeasures MAY also be included. The
same attributes as those defined in Section 8.1.5 are applicable for
describing the attacks detected and mitigated at the DOTS server
domain.
The "ietf-dots-telemetry" YANG module (Section 11.1) augments the
'mitigation-scope' message type defined in the "ietf-dots-signal-
channel" module [RFC9132] with telemetry data as depicted in
Figure 46.
augment-structure /dots-signal:dots-signal/dots-signal:message-type
/dots-signal:mitigation-scope/dots-signal:scope:
+-- (direction)?
| +--:(server-to-client-only)
| +-- total-traffic* [unit]
| | +-- unit unit
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- total-attack-connection
| +-- connection-c
| | +-- low-percentile-g? yang:gauge64
| | +-- mid-percentile-g? yang:gauge64
| | +-- high-percentile-g? yang:gauge64
| | +-- peak-g? yang:gauge64
| | +-- current-g? yang:gauge64
| +-- embryonic-c
| | ...
| +-- connection-ps-c
| | ...
| +-- request-ps-c
| | ...
| +-- partial-request-c
| ...
+-- total-attack-traffic* [unit]
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- attack-detail* [vendor-id attack-id]
+-- vendor-id uint32
+-- attack-id uint32
+-- attack-description? string
+-- attack-severity? attack-severity
+-- start-time? uint64
+-- end-time? uint64
+-- source-count
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- top-talker
+-- talker* [source-prefix]
+-- spoofed-status? boolean
+-- source-prefix inet:ip-prefix
+-- source-port-range* [lower-port]
| +-- lower-port inet:port-number
| +-- upper-port? inet:port-number
+-- source-icmp-type-range* [lower-type]
| +-- lower-type uint8
| +-- upper-type? uint8
+-- total-attack-traffic* [unit]
| +-- unit unit
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- total-attack-connection
+-- connection-c
| +-- low-percentile-g? yang:gauge64
| +-- mid-percentile-g? yang:gauge64
| +-- high-percentile-g? yang:gauge64
| +-- peak-g? yang:gauge64
| +-- current-g? yang:gauge64
+-- embryonic-c
| ...
+-- connection-ps-c
| ...
+-- request-ps-c
| ...
+-- partial-request-c
...
Figure 46: DOTS Server-to-Client Mitigation Status Telemetry Tree
Structure
Figure 47 shows an example of an asynchronous notification of attack
mitigation status from the DOTS server. This notification signals
both the mid-percentile value of processed attack traffic and the
peak count of unique sources involved in the attack.
{
"ietf-dots-signal-channel:mitigation-scope": {
"scope": [
{
"mid": 12332,
"mitigation-start": "1507818434",
"alias-name": [
"https1",
"https2"
],
"lifetime": 1600,
"status": "attack-successfully-mitigated",
"bytes-dropped": "134334555",
"bps-dropped": "43344",
"pkts-dropped": "333334444",
"pps-dropped": "432432",
"ietf-dots-telemetry:total-attack-traffic": [
{
"unit": "megabit-ps",
"mid-percentile-g": "752"
}
],
"ietf-dots-telemetry:attack-detail": [
{
"vendor-id": 32473,
"attack-id": 77,
"source-count": {
"peak-g": "12683"
}
}
]
}
]
}
}
Figure 47: Response Body of a Mitigation Status with Telemetry
Attributes, Depicted as per Section 5.6
DOTS clients can filter out the asynchronous notifications from the
DOTS server by indicating one or more Uri-Query options in its GET
request. A Uri-Query option can include the following parameters:
'target-prefix', 'target-port', 'target-protocol', 'target-fqdn',
'target-uri', 'alias-name', and 'c' (content) (Section 5.4). The
considerations discussed in Section 8.3 MUST be followed to include
multiple query values, ranges ('target-port', 'target-protocol'), and
wildcard names ('target-fqdn', 'target-uri').
An example of a request to subscribe to asynchronous notifications
bound to the "https1" alias is shown in Figure 48.
Header: GET (Code=0.01)
Uri-Path: ".well-known"
Uri-Path: "dots"
Uri-Path: "mitigate"
Uri-Path: "cuid=dz6pHjaADkaFTbjr0JGBpw"
Uri-Path: "mid=12332"
Uri-Query: "target-alias=https1"
Observe: 0
Figure 48: GET Request to Receive Asynchronous Notifications
Filtered Using Uri-Query
If the target query does not match the target of the enclosed 'mid'
as maintained by the DOTS server, the latter MUST respond with a 4.04
(Not Found) error Response Code. The DOTS server MUST NOT add a new
Observe entry if this query overlaps with an existing Observe entry.
In such a case, the DOTS server replies with a 4.09 (Conflict)
Response Code.
10. Error Handling
A list of common CoAP errors that are implemented by DOTS servers is
provided in Section 9 of [RFC9132]. The following additional error
cases apply for the telemetry extension:
* 4.00 (Bad Request) is returned by the DOTS server when the DOTS
client has sent a request that violates the DOTS telemetry
extension.
* 4.04 (Not Found) is returned by the DOTS server when the DOTS
client is requesting a 'tsid' or 'tmid' that is not valid.
* 4.00 (Bad Request) is returned by the DOTS server when the DOTS
client has sent a request with invalid query types (e.g., not
supported, malformed).
* 4.04 (Not Found) is returned by the DOTS server when the DOTS
client has sent a request with a target query that does not match
the target of the enclosed 'mid' as maintained by the DOTS server.
As indicated in Section 9 of [RFC9132], an additional plaintext
diagnostic payload (Section 5.5.2 of [RFC7252]) to help with
troubleshooting is returned in the body of the response.
11. YANG Modules
11.1. DOTS Signal Channel Telemetry YANG Module
This module uses types defined in [RFC6991] and [RFC8345]. It also
reuses a grouping from [RFC8783].
<CODE BEGINS> file "ietf-dots-telemetry@2022-06-20.yang"
module ietf-dots-telemetry {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-dots-telemetry";
prefix dots-telemetry;
import ietf-dots-signal-channel {
prefix dots-signal;
reference
"RFC 9132: Distributed Denial-of-Service Open Threat
Signaling (DOTS) Signal Channel Specification";
}
import ietf-dots-data-channel {
prefix data-channel;
reference
"RFC 8783: Distributed Denial-of-Service Open Threat
Signaling (DOTS) Data Channel Specification";
}
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types, Section 3";
}
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types, Section 4";
}
import ietf-network-topology {
prefix nt;
reference
"RFC 8345: A YANG Data Model for Network Topologies,
Section 6.2";
}
import ietf-yang-structure-ext {
prefix sx;
reference
"RFC 8791: YANG Data Structure Extensions";
}
organization
"IETF DDoS Open Threat Signaling (DOTS) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dots/>
WG List: <mailto:dots@ietf.org>
Author: Mohamed Boucadair
<mailto:mohamed.boucadair@orange.com>
Author: Konda, Tirumaleswar Reddy.K
<mailto:kondtir@gmail.com>";
description
"This module contains YANG definitions for the signaling
of DOTS telemetry data exchanged between a DOTS client and
a DOTS server by means of the DOTS signal channel.
Copyright (c) 2022 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Revised BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC 9244; see the
RFC itself for full legal notices.";
revision 2022-06-20 {
description
"Initial revision.";
reference
"RFC 9244: Distributed Denial-of-Service Open Threat
Signaling (DOTS) Telemetry";
}
typedef attack-severity {
type enumeration {
enum none {
value 1;
description
"No effect on the DOTS client domain.";
}
enum low {
value 2;
description
"Minimal effect on the DOTS client domain.";
}
enum medium {
value 3;
description
"A subset of DOTS client domain resources is
out of service.";
}
enum high {
value 4;
description
"The DOTS client domain is under extremely severe
conditions.";
}
enum unknown {
value 5;
description
"The impact of the attack is not known.";
}
}
description
"Enumeration for attack severity.";
reference
"RFC 7970: The Incident Object Description Exchange
Format Version 2, Section 3.12.2";
}
typedef unit-class {
type enumeration {
enum packet-ps {
value 1;
description
"Packets per second (pps).";
}
enum bit-ps {
value 2;
description
"Bits per second (bps).";
}
enum byte-ps {
value 3;
description
"Bytes per second (Bps).";
}
}
description
"Enumeration to indicate which unit class is used.
These classes are supported: pps, bps, and Bps.";
}
typedef unit {
type enumeration {
enum packet-ps {
value 1;
description
"Packets per second (pps).";
}
enum bit-ps {
value 2;
description
"Bits per second (bps).";
}
enum byte-ps {
value 3;
description
"Bytes per second (Bps).";
}
enum kilopacket-ps {
value 4;
description
"Kilo packets per second (kpps).";
}
enum kilobit-ps {
value 5;
description
"Kilobits per second (kbps).";
}
enum kilobyte-ps {
value 6;
description
"Kilobytes per second (kBps).";
}
enum megapacket-ps {
value 7;
description
"Mega packets per second (Mpps).";
}
enum megabit-ps {
value 8;
description
"Megabits per second (Mbps).";
}
enum megabyte-ps {
value 9;
description
"Megabytes per second (MBps).";
}
enum gigapacket-ps {
value 10;
description
"Giga packets per second (Gpps).";
}
enum gigabit-ps {
value 11;
description
"Gigabits per second (Gbps).";
}
enum gigabyte-ps {
value 12;
description
"Gigabytes per second (GBps).";
}
enum terapacket-ps {
value 13;
description
"Tera packets per second (Tpps).";
}
enum terabit-ps {
value 14;
description
"Terabits per second (Tbps).";
}
enum terabyte-ps {
value 15;
description
"Terabytes per second (TBps).";
}
enum petapacket-ps {
value 16;
description
"Peta packets per second (Ppps).";
}
enum petabit-ps {
value 17;
description
"Petabits per second (Pbps).";
}
enum petabyte-ps {
value 18;
description
"Petabytes per second (PBps).";
}
enum exapacket-ps {
value 19;
description
"Exa packets per second (Epps).";
}
enum exabit-ps {
value 20;
description
"Exabits per second (Ebps).";
}
enum exabyte-ps {
value 21;
description
"Exabytes per second (EBps).";
}
enum zettapacket-ps {
value 22;
description
"Zetta packets per second (Zpps).";
}
enum zettabit-ps {
value 23;
description
"Zettabits per second (Zbps).";
}
enum zettabyte-ps {
value 24;
description
"Zettabytes per second (ZBps).";
}
}
description
"Enumeration to indicate which unit is used.
Only one unit per unit class is used owing to
unit auto-scaling.";
}
typedef interval {
type enumeration {
enum 5-minutes {
value 1;
description
"5 minutes.";
}
enum 10-minutes {
value 2;
description
"10 minutes.";
}
enum 30-minutes {
value 3;
description
"30 minutes.";
}
enum hour {
value 4;
description
"Hour.";
}
enum day {
value 5;
description
"Day.";
}
enum week {
value 6;
description
"Week.";
}
enum month {
value 7;
description
"Month.";
}
}
description
"Enumeration to indicate the overall measurement period.";
}
typedef sample {
type enumeration {
enum second {
value 1;
description
"One-second measurement period.";
}
enum 5-seconds {
value 2;
description
"5-second measurement period.";
}
enum 30-seconds {
value 3;
description
"30-second measurement period.";
}
enum minute {
value 4;
description
"One-minute measurement period.";
}
enum 5-minutes {
value 5;
description
"5-minute measurement period.";
}
enum 10-minutes {
value 6;
description
"10-minute measurement period.";
}
enum 30-minutes {
value 7;
description
"30-minute measurement period.";
}
enum hour {
value 8;
description
"One-hour measurement period.";
}
}
description
"Enumeration to indicate the sampling period.";
}
typedef percentile {
type decimal64 {
fraction-digits 2;
}
description
"The nth percentile of a set of data is the
value at which n percent of the data is below it.";
}
typedef query-type {
type enumeration {
enum target-prefix {
value 1;
description
"Query based on target prefix.";
}
enum target-port {
value 2;
description
"Query based on target port number.";
}
enum target-protocol {
value 3;
description
"Query based on target protocol.";
}
enum target-fqdn {
value 4;
description
"Query based on target FQDN.";
}
enum target-uri {
value 5;
description
"Query based on target URI.";
}
enum target-alias {
value 6;
description
"Query based on target alias.";
}
enum mid {
value 7;
description
"Query based on mitigation identifier (mid).";
}
enum source-prefix {
value 8;
description
"Query based on source prefix.";
}
enum source-port {
value 9;
description
"Query based on source port number.";
}
enum source-icmp-type {
value 10;
description
"Query based on ICMP type.";
}
enum content {
value 11;
description
"Query based on the 'c' (content) Uri-Query option,
which is used to control the selection of configuration
and non-configuration data nodes.";
reference
"RFC 9132: Distributed Denial-of-Service Open Threat
Signaling (DOTS) Signal Channel
Specification, Section 4.4.2";
}
}
description
"Enumeration of support for query types that can be used
in a GET request to filter out data. Requests with
invalid query types (e.g., not supported, malformed)
received by the DOTS server are rejected with
a 4.00 (Bad Request) Response Code.";
}
grouping telemetry-parameters {
description
"A grouping that includes a set of parameters that
are used to prepare the reported telemetry data.
The grouping indicates a measurement interval,
a measurement sample period, and
low-percentile/mid-percentile/high-percentile values.";
leaf measurement-interval {
type interval;
description
"Defines the period during which percentiles are
computed.";
}
leaf measurement-sample {
type sample;
description
"Defines the time distribution for measuring
values that are used to compute percentiles.
The measurement sample value must be less than the
measurement interval value.";
}
leaf low-percentile {
type percentile;
default "10.00";
description
"Low-percentile. If set to '0', this means that
the use of low-percentile values is disabled.";
}
leaf mid-percentile {
type percentile;
must '. >= ../low-percentile' {
error-message
"The mid-percentile must be greater than
or equal to the low-percentile.";
}
default "50.00";
description
"Mid-percentile. If set to the same value as
'low-percentile', this means that the use of
mid-percentile values is disabled.";
}
leaf high-percentile {
type percentile;
must '. >= ../mid-percentile' {
error-message
"The high-percentile must be greater than
or equal to the mid-percentile.";
}
default "90.00";
description
"High-percentile. If set to the same value as
'mid-percentile', this means that the use of
high-percentile values is disabled.";
}
}
grouping percentile-and-peak {
description
"Generic grouping for percentile and peak values.";
leaf low-percentile-g {
type yang:gauge64;
description
"Low-percentile value.";
}
leaf mid-percentile-g {
type yang:gauge64;
description
"Mid-percentile value.";
}
leaf high-percentile-g {
type yang:gauge64;
description
"High-percentile value.";
}
leaf peak-g {
type yang:gauge64;
description
"Peak value.";
}
}
grouping percentile-peak-and-current {
description
"Generic grouping for percentile and peak values.";
uses percentile-and-peak;
leaf current-g {
type yang:gauge64;
description
"Current value.";
}
}
grouping unit-config {
description
"Generic grouping for unit configuration.";
list unit-config {
key "unit";
description
"Controls which unit classes are allowed when sharing
telemetry data.";
leaf unit {
type unit-class;
description
"Can be 'packet-ps', 'bit-ps', or 'byte-ps'.";
}
leaf unit-status {
type boolean;
mandatory true;
description
"Enable/disable the use of the measurement unit class.";
}
}
}
grouping traffic-unit {
description
"Grouping of traffic as a function of the
measurement unit.";
leaf unit {
type unit;
description
"The traffic can be measured using unit classes:
'packet-ps', 'bit-ps', or 'byte-ps'. DOTS agents
auto-scale to the appropriate units (e.g., 'megabit-ps',
'kilobit-ps').";
}
uses percentile-and-peak;
}
grouping traffic-unit-all {
description
"Grouping of traffic as a function of the measurement unit,
including current values.";
uses traffic-unit;
leaf current-g {
type yang:gauge64;
description
"Current observed value.";
}
}
grouping traffic-unit-protocol {
description
"Grouping of traffic of a given transport protocol as
a function of the measurement unit.";
leaf protocol {
type uint8;
description
"The transport protocol.
Values are taken from the IANA 'Protocol Numbers'
registry:
<https://www.iana.org/assignments/protocol-numbers/>.
For example, this parameter contains 6 for TCP,
17 for UDP, 33 for the Datagram Congestion Control
Protocol (DCCP), or 132 for the Stream Control
Transmission Protocol (SCTP).";
}
uses traffic-unit;
}
grouping traffic-unit-protocol-all {
description
"Grouping of traffic of a given transport protocol as
a function of the measurement unit, including current
values.";
uses traffic-unit-protocol;
leaf current-g {
type yang:gauge64;
description
"Current observed value.";
}
}
grouping traffic-unit-port {
description
"Grouping of traffic bound to a port number as
a function of the measurement unit.";
leaf port {
type inet:port-number;
description
"Port number used by a transport protocol.";
}
uses traffic-unit;
}
grouping traffic-unit-port-all {
description
"Grouping of traffic bound to a port number as
a function of the measurement unit, including
current values.";
uses traffic-unit-port;
leaf current-g {
type yang:gauge64;
description
"Current observed value.";
}
}
grouping total-connection-capacity {
description
"Total connection capacities for various types of
connections, as well as overall capacity. These data nodes
are useful for detecting resource-consuming DDoS attacks.";
leaf connection {
type uint64;
description
"The maximum number of simultaneous connections that
are allowed to the target server.";
}
leaf connection-client {
type uint64;
description
"The maximum number of simultaneous connections that
are allowed to the target server per client.";
}
leaf embryonic {
type uint64;
description
"The maximum number of simultaneous embryonic connections
that are allowed to the target server. The term
'embryonic connection' refers to a connection whose
connection handshake is not finished. Embryonic
connections are only possible in connection-oriented
transport protocols like TCP or SCTP.";
}
leaf embryonic-client {
type uint64;
description
"The maximum number of simultaneous embryonic connections
that are allowed to the target server per client.";
}
leaf connection-ps {
type uint64;
description
"The maximum number of new connections allowed per second
to the target server.";
}
leaf connection-client-ps {
type uint64;
description
"The maximum number of new connections allowed per second
to the target server per client.";
}
leaf request-ps {
type uint64;
description
"The maximum number of requests allowed per second
to the target server.";
}
leaf request-client-ps {
type uint64;
description
"The maximum number of requests allowed per second
to the target server per client.";
}
leaf partial-request-max {
type uint64;
description
"The maximum number of outstanding partial requests
that are allowed to the target server.";
}
leaf partial-request-client-max {
type uint64;
description
"The maximum number of outstanding partial requests
that are allowed to the target server per client.";
}
}
grouping total-connection-capacity-protocol {
description
"Total connection capacity per protocol. These data nodes
are useful for detecting resource-consuming DDoS attacks.";
leaf protocol {
type uint8;
description
"The transport protocol.
Values are taken from the IANA 'Protocol Numbers'
registry:
<https://www.iana.org/assignments/protocol-numbers/>.";
}
uses total-connection-capacity;
}
grouping connection-percentile-and-peak {
description
"A set of data nodes that represent the attack
characteristics.";
container connection-c {
uses percentile-and-peak;
description
"The number of simultaneous attack connections to
the target server.";
}
container embryonic-c {
uses percentile-and-peak;
description
"The number of simultaneous embryonic connections to
the target server.";
}
container connection-ps-c {
uses percentile-and-peak;
description
"The number of attack connections per second to
the target server.";
}
container request-ps-c {
uses percentile-and-peak;
description
"The number of attack requests per second to
the target server.";
}
container partial-request-c {
uses percentile-and-peak;
description
"The number of attack partial requests to
the target server.";
}
}
grouping connection-all {
description
"Total attack connections, including current values.";
container connection-c {
uses percentile-peak-and-current;
description
"The number of simultaneous attack connections to
the target server.";
}
container embryonic-c {
uses percentile-peak-and-current;
description
"The number of simultaneous embryonic connections to
the target server.";
}
container connection-ps-c {
uses percentile-peak-and-current;
description
"The number of attack connections per second to
the target server.";
}
container request-ps-c {
uses percentile-peak-and-current;
description
"The number of attack requests per second to
the target server.";
}
container partial-request-c {
uses percentile-peak-and-current;
description
"The number of attack partial requests to
the target server.";
}
}
grouping connection-protocol {
description
"Total attack connections.";
leaf protocol {
type uint8;
description
"The transport protocol.
Values are taken from the IANA 'Protocol Numbers'
registry:
<https://www.iana.org/assignments/protocol-numbers/>.";
}
uses connection-percentile-and-peak;
}
grouping connection-port {
description
"Total attack connections per port number.";
leaf protocol {
type uint8;
description
"The transport protocol.
Values are taken from the IANA 'Protocol Numbers'
registry:
<https://www.iana.org/assignments/protocol-numbers/>.";
}
leaf port {
type inet:port-number;
description
"Port number.";
}
uses connection-percentile-and-peak;
}
grouping connection-protocol-all {
description
"Total attack connections per protocol, including current
values.";
leaf protocol {
type uint8;
description
"The transport protocol.
Values are taken from the IANA 'Protocol Numbers'
registry:
<https://www.iana.org/assignments/protocol-numbers/>.";
}
uses connection-all;
}
grouping connection-protocol-port-all {
description
"Total attack connections per port number, including current
values.";
leaf protocol {
type uint8;
description
"The transport protocol.
Values are taken from the IANA 'Protocol Numbers'
registry:
<https://www.iana.org/assignments/protocol-numbers/>.";
}
leaf port {
type inet:port-number;
description
"Port number.";
}
uses connection-all;
}
grouping attack-detail {
description
"Various details that describe the ongoing
attacks that need to be mitigated by the DOTS server.
The attack details need to cover well-known and common
attacks (such as a SYN flood) along with new emerging or
vendor-specific attacks.";
leaf vendor-id {
type uint32;
description
"The Vendor ID is a security vendor's Private Enterprise
Number as registered with IANA.";
reference
"IANA: Private Enterprise Numbers
(https://www.iana.org/assignments/enterprise-numbers/)";
}
leaf attack-id {
type uint32;
description
"Unique identifier assigned by the vendor for the attack.";
}
leaf description-lang {
type string {
pattern '((([A-Za-z]{2,3}(-[A-Za-z]{3}(-[A-Za-z]{3})'
+ '{0,2})?)|[A-Za-z]{4}|[A-Za-z]{5,8})(-[A-Za-z]{4})'
+ '?(-([A-Za-z]{2}|[0-9]{3}))?(-([A-Za-z0-9]{5,8}'
+ '|([0-9][A-Za-z0-9]{3})))*(-[0-9A-WYZa-wyz]'
+ '(-([A-Za-z0-9]{2,8}))+)*(-[Xx](-([A-Za-z0-9]'
+ '{1,8}))+)?|[Xx](-([A-Za-z0-9]{1,8}))+|'
+ '(([Ee][Nn]-[Gg][Bb]-[Oo][Ee][Dd]|[Ii]-'
+ '[Aa][Mm][Ii]|[Ii]-[Bb][Nn][Nn]|[Ii]-'
+ '[Dd][Ee][Ff][Aa][Uu][Ll][Tt]|[Ii]-'
+ '[Ee][Nn][Oo][Cc][Hh][Ii][Aa][Nn]'
+ '|[Ii]-[Hh][Aa][Kk]|'
+ '[Ii]-[Kk][Ll][Ii][Nn][Gg][Oo][Nn]|'
+ '[Ii]-[Ll][Uu][Xx]|[Ii]-[Mm][Ii][Nn][Gg][Oo]|'
+ '[Ii]-[Nn][Aa][Vv][Aa][Jj][Oo]|[Ii]-[Pp][Ww][Nn]|'
+ '[Ii]-[Tt][Aa][Oo]|[Ii]-[Tt][Aa][Yy]|'
+ '[Ii]-[Tt][Ss][Uu]|[Ss][Gg][Nn]-[Bb][Ee]-[Ff][Rr]|'
+ '[Ss][Gg][Nn]-[Bb][Ee]-[Nn][Ll]|[Ss][Gg][Nn]-'
+ '[Cc][Hh]-[Dd][Ee])|([Aa][Rr][Tt]-'
+ '[Ll][Oo][Jj][Bb][Aa][Nn]|[Cc][Ee][Ll]-'
+ '[Gg][Aa][Uu][Ll][Ii][Ss][Hh]|'
+ '[Nn][Oo]-[Bb][Oo][Kk]|[Nn][Oo]-'
+ '[Nn][Yy][Nn]|[Zz][Hh]-[Gg][Uu][Oo][Yy][Uu]|'
+ '[Zz][Hh]-[Hh][Aa][Kk][Kk][Aa]|[Zz][Hh]-'
+ '[Mm][Ii][Nn]|[Zz][Hh]-[Mm][Ii][Nn]-'
+ '[Nn][Aa][Nn]|[Zz][Hh]-[Xx][Ii][Aa][Nn][Gg])))';
}
default "en-US";
description
"Indicates the language tag that is used for
'attack-description'.";
reference
"RFC 5646: Tags for Identifying Languages, Section 2.1";
}
leaf attack-description {
type string;
description
"Textual representation of the attack description.
Natural Language Processing techniques (e.g.,
word embedding) might provide some utility in mapping
the attack description to an attack type.";
}
leaf attack-severity {
type attack-severity;
description
"Severity level of an attack. How this level is
determined is implementation specific.";
}
leaf start-time {
type uint64;
description
"The time the attack started. The start time is
represented in seconds relative to
1970-01-01T00:00:00Z.";
}
leaf end-time {
type uint64;
description
"The time the attack ended. The end time is represented
in seconds relative to 1970-01-01T00:00:00Z.";
}
container source-count {
description
"Indicates the count of unique sources involved
in the attack.";
uses percentile-and-peak;
leaf current-g {
type yang:gauge64;
description
"Current observed value.";
}
}
}
grouping talker {
description
"Defines generic data related to top talkers.";
leaf spoofed-status {
type boolean;
description
"When set to 'true', it indicates whether this address
is spoofed.";
}
leaf source-prefix {
type inet:ip-prefix;
description
"IPv4 or IPv6 prefix identifying the attacker(s).";
}
list source-port-range {
key "lower-port";
description
"Port range. When only 'lower-port' is
present, it represents a single port number.";
leaf lower-port {
type inet:port-number;
description
"Lower port number of the port range.";
}
leaf upper-port {
type inet:port-number;
must '. >= ../lower-port' {
error-message
"The upper port number must be greater than
or equal to the lower port number.";
}
description
"Upper port number of the port range.";
}
}
list source-icmp-type-range {
key "lower-type";
description
"ICMP type range. When only 'lower-type' is
present, it represents a single ICMP type.";
leaf lower-type {
type uint8;
description
"Lower ICMP type of the ICMP type range.";
}
leaf upper-type {
type uint8;
must '. >= ../lower-type' {
error-message
"The upper ICMP type must be greater than
or equal to the lower ICMP type.";
}
description
"Upper type of the ICMP type range.";
}
}
list total-attack-traffic {
key "unit";
description
"Total attack traffic issued from this source.";
uses traffic-unit-all;
}
}
grouping top-talker-aggregate {
description
"An aggregate of top attack sources. This aggregate is
typically used when included in a mitigation request.";
list talker {
key "source-prefix";
description
"Refers to a top talker that is identified by an IPv4
or IPv6 prefix identifying the attacker(s).";
uses talker;
container total-attack-connection {
description
"Total attack connections issued from this source.";
uses connection-all;
}
}
}
grouping top-talker {
description
"Top attack sources with detailed per-protocol
structure.";
list talker {
key "source-prefix";
description
"Refers to a top talker that is identified by an IPv4
or IPv6 prefix identifying the attacker(s).";
uses talker;
list total-attack-connection-protocol {
key "protocol";
description
"Total attack connections issued from this source.";
uses connection-protocol-all;
}
}
}
grouping baseline {
description
"Grouping for the telemetry baseline.";
uses data-channel:target;
leaf-list alias-name {
type string;
description
"An alias name that points to an IP resource.
An IP resource can be a router, a host,
an Internet of Things (IoT) object, a server, etc.";
}
list total-traffic-normal {
key "unit";
description
"Total traffic normal baselines.";
uses traffic-unit;
}
list total-traffic-normal-per-protocol {
key "unit protocol";
description
"Total traffic normal baselines per protocol.";
uses traffic-unit-protocol;
}
list total-traffic-normal-per-port {
key "unit port";
description
"Total traffic normal baselines per port number.";
uses traffic-unit-port;
}
list total-connection-capacity {
key "protocol";
description
"Total connection capacity.";
uses total-connection-capacity-protocol;
}
list total-connection-capacity-per-port {
key "protocol port";
description
"Total connection capacity per port number.";
leaf port {
type inet:port-number;
description
"The target port number.";
}
uses total-connection-capacity-protocol;
}
}
grouping pre-or-ongoing-mitigation {
description
"Grouping for the telemetry data.";
list total-traffic {
key "unit";
description
"Total traffic.";
uses traffic-unit-all;
}
list total-traffic-protocol {
key "unit protocol";
description
"Total traffic per protocol.";
uses traffic-unit-protocol-all;
}
list total-traffic-port {
key "unit port";
description
"Total traffic per port number.";
uses traffic-unit-port-all;
}
list total-attack-traffic {
key "unit";
description
"Total attack traffic.";
uses traffic-unit-all;
}
list total-attack-traffic-protocol {
key "unit protocol";
description
"Total attack traffic per protocol.";
uses traffic-unit-protocol-all;
}
list total-attack-traffic-port {
key "unit port";
description
"Total attack traffic per port number.";
uses traffic-unit-port-all;
}
list total-attack-connection-protocol {
key "protocol";
description
"Total attack connections.";
uses connection-protocol-all;
}
list total-attack-connection-port {
key "protocol port";
description
"Total attack connections per target port number.";
uses connection-protocol-port-all;
}
list attack-detail {
key "vendor-id attack-id";
description
"Provides a set of attack details.";
uses attack-detail;
container top-talker {
description
"Lists the top attack sources.";
uses top-talker;
}
}
}
sx:augment-structure "/dots-signal:dots-signal"
+ "/dots-signal:message-type"
+ "/dots-signal:mitigation-scope"
+ "/dots-signal:scope" {
description
"Extends mitigation scope with telemetry update data.";
choice direction {
description
"Indicates the communication direction in which the
data nodes can be included.";
case server-to-client-only {
description
"These data nodes appear only in a mitigation message
sent from the server to the client.";
list total-traffic {
key "unit";
description
"Total traffic.";
uses traffic-unit-all;
}
container total-attack-connection {
description
"Total attack connections.";
uses connection-all;
}
}
}
list total-attack-traffic {
key "unit";
description
"Total attack traffic.";
uses traffic-unit-all;
}
list attack-detail {
key "vendor-id attack-id";
description
"Attack details.";
uses attack-detail;
container top-talker {
description
"Top attack sources.";
uses top-talker-aggregate;
}
}
}
sx:structure dots-telemetry {
description
"Main structure for DOTS telemetry messages.";
choice telemetry-message-type {
description
"Can be 'telemetry-setup' or telemetry data.";
case telemetry-setup {
description
"Indicates that the message is about telemetry setup.";
choice direction {
description
"Indicates the communication direction in which the
data nodes can be included.";
case server-to-client-only {
description
"These data nodes appear only in a telemetry message
sent from the server to the client.";
container max-config-values {
description
"Maximum acceptable configuration values.";
uses telemetry-parameters;
leaf server-originated-telemetry {
type boolean;
default "false";
description
"Indicates whether the DOTS server can be
instructed to send pre-or-ongoing-mitigation
telemetry. If set to 'false' or the data node
is not present, this is an indication that
the server does not support this capability.";
}
leaf telemetry-notify-interval {
type uint16 {
range "1 .. 3600";
}
units "seconds";
must '. >= ../../min-config-values'
+ '/telemetry-notify-interval' {
error-message
"The value must be greater than or equal
to the 'telemetry-notify-interval' value in
the 'min-config-values' attribute";
}
description
"Minimum number of seconds between successive
telemetry notifications.";
}
}
container min-config-values {
description
"Minimum acceptable configuration values.";
uses telemetry-parameters;
leaf telemetry-notify-interval {
type uint16 {
range "1 .. 3600";
}
units "seconds";
description
"Minimum number of seconds between successive
telemetry notifications.";
}
}
container supported-unit-classes {
description
"Supported unit classes and default activation
status.";
uses unit-config;
}
leaf-list supported-query-type {
type query-type;
description
"Indicates which query types are supported by
the server. If the server does not announce
the query types it supports, the client will
be unable to use any of the potential
'query-type' values to reduce the returned data
content from the server.";
}
}
}
list telemetry {
description
"The telemetry data per DOTS client. The keys
of the list are 'cuid' and 'tsid', but these keys are
not represented here because these keys are conveyed
as mandatory Uri-Paths in requests. Omitting keys
is compliant with RFC 8791.";
reference
"RFC 8791: YANG Data Structure Extensions";
choice direction {
description
"Indicates the communication direction in which the
data nodes can be included.";
case server-to-client-only {
description
"These data nodes appear only in a telemetry
message sent from the server to the client.";
leaf tsid {
type uint32;
description
"A client-assigned identifier for the DOTS
telemetry setup data.";
}
}
}
choice setup-type {
description
"Can be a mitigation configuration, a pipe capacity,
or a baseline message.";
case telemetry-config {
description
"Used to set telemetry parameters such as setting
low-, mid-, and high-percentile values.";
container current-config {
description
"Current telemetry configuration values.";
uses telemetry-parameters;
uses unit-config;
leaf server-originated-telemetry {
type boolean;
description
"Used by a DOTS client to enable/disable
whether it requests pre-or-ongoing-mitigation
telemetry from the DOTS server.";
}
leaf telemetry-notify-interval {
type uint16 {
range "1 .. 3600";
}
units "seconds";
description
"Minimum number of seconds between successive
telemetry notifications.";
}
}
}
case pipe {
description
"Total pipe capacity of a DOTS client domain.";
list total-pipe-capacity {
key "link-id unit";
description
"Total pipe capacity of a DOTS client domain.";
leaf link-id {
type nt:link-id;
description
"Identifier of an interconnection link of
the DOTS client domain.";
}
leaf capacity {
type uint64;
mandatory true;
description
"Pipe capacity. This attribute is mandatory
when 'total-pipe-capacity' is included in a
message.";
}
leaf unit {
type unit;
description
"The traffic can be measured using unit
classes: packets per second (pps), bits per
second (bps), and/or bytes per second
(Bps).
For a given unit class, the DOTS agents
auto-scale to the appropriate units (e.g.,
'megabit-ps', 'kilobit-ps').";
}
}
}
case baseline {
description
"Traffic baseline information related to a DOTS
client domain.";
list baseline {
key "id";
description
"Traffic baseline information related to a DOTS
client domain.";
leaf id {
type uint32;
must '. >= 1';
description
"An identifier that uniquely identifies a
baseline entry communicated by a
DOTS client.";
}
uses baseline;
}
}
}
}
}
case telemetry {
description
"Telemetry information.";
list pre-or-ongoing-mitigation {
description
"Pre-or-ongoing-mitigation telemetry per DOTS client.
The keys of the list are 'cuid' and 'tmid', but these
keys are not represented here because these keys are
conveyed as mandatory Uri-Paths in requests.
Omitting keys is compliant with RFC 8791.";
reference
"RFC 8791: YANG Data Structure Extensions";
choice direction {
description
"Indicates the communication direction in which the
data nodes can be included.";
case server-to-client-only {
description
"These data nodes appear only in a telemetry
message sent from the server to the client.";
leaf tmid {
type uint32;
description
"A client-assigned identifier for the DOTS
telemetry data.";
}
}
}
container target {
description
"Indicates the target. At least one of the
attributes 'target-prefix', 'target-fqdn',
'target-uri', 'alias-name', or 'mid-list'
must be present in the target definition.";
uses data-channel:target;
leaf-list alias-name {
type string;
description
"An alias name that points to a resource.";
}
leaf-list mid-list {
type uint32;
description
"Reference to a list of associated mitigation
requests.";
reference
"RFC 9132: Distributed Denial-of-Service Open
Threat Signaling (DOTS) Signal Channel
Specification, Section 4.4.1";
}
}
uses pre-or-ongoing-mitigation;
}
}
}
}
}
<CODE ENDS>
11.2. Vendor Attack Mapping Details YANG Module
<CODE BEGINS> file "ietf-dots-mapping@2022-06-20.yang"
module ietf-dots-mapping {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-dots-mapping";
prefix dots-mapping;
import ietf-dots-data-channel {
prefix data-channel;
reference
"RFC 8783: Distributed Denial-of-Service Open Threat
Signaling (DOTS) Data Channel Specification";
}
organization
"IETF DDoS Open Threat Signaling (DOTS) Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/dots/>
WG List: <mailto:dots@ietf.org>
Author: Mohamed Boucadair
<mailto:mohamed.boucadair@orange.com>
Author: Jon Shallow
<mailto:supjps-ietf@jpshallow.com>";
description
"This module contains YANG definitions for the sharing
of DDoS attack mapping details between a DOTS client and
a DOTS server by means of the DOTS data channel.
Copyright (c) 2022 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject to
the license terms contained in, the Revised BSD License set
forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC 9244; see the
RFC itself for full legal notices.";
revision 2022-06-20 {
description
"Initial revision.";
reference
"RFC 9244: Distributed Denial-of-Service Open Threat
Signaling (DOTS) Telemetry";
}
feature dots-telemetry {
description
"This feature indicates that DOTS telemetry data can be
shared between DOTS clients and servers.";
}
grouping attack-mapping {
description
"A set of information used for sharing vendor attack mapping
information with a peer.";
list vendor {
key "vendor-id";
description
"Vendor attack mapping information related to the
client/server.";
leaf vendor-id {
type uint32;
description
"The Vendor ID is a security vendor's Private Enterprise
Number as registered with IANA.";
reference
"IANA: Private Enterprise Numbers
(https://www.iana.org/assignments/enterprise-numbers/)";
}
leaf vendor-name {
type string;
description
"The name of the vendor (e.g., company A).";
}
leaf description-lang {
type string {
pattern '((([A-Za-z]{2,3}(-[A-Za-z]{3}(-[A-Za-z]{3})'
+ '{0,2})?)|[A-Za-z]{4}|[A-Za-z]{5,8})(-[A-Za-z]{4})'
+ '?(-([A-Za-z]{2}|[0-9]{3}))?(-([A-Za-z0-9]{5,8}'
+ '|([0-9][A-Za-z0-9]{3})))*(-[0-9A-WYZa-wyz]'
+ '(-([A-Za-z0-9]{2,8}))+)*(-[Xx](-([A-Za-z0-9]'
+ '{1,8}))+)?|[Xx](-([A-Za-z0-9]{1,8}))+|'
+ '(([Ee][Nn]-[Gg][Bb]-[Oo][Ee][Dd]|[Ii]-'
+ '[Aa][Mm][Ii]|[Ii]-[Bb][Nn][Nn]|[Ii]-'
+ '[Dd][Ee][Ff][Aa][Uu][Ll][Tt]|[Ii]-'
+ '[Ee][Nn][Oo][Cc][Hh][Ii][Aa][Nn]'
+ '|[Ii]-[Hh][Aa][Kk]|'
+ '[Ii]-[Kk][Ll][Ii][Nn][Gg][Oo][Nn]|'
+ '[Ii]-[Ll][Uu][Xx]|[Ii]-[Mm][Ii][Nn][Gg][Oo]|'
+ '[Ii]-[Nn][Aa][Vv][Aa][Jj][Oo]|[Ii]-[Pp][Ww][Nn]|'
+ '[Ii]-[Tt][Aa][Oo]|[Ii]-[Tt][Aa][Yy]|'
+ '[Ii]-[Tt][Ss][Uu]|[Ss][Gg][Nn]-[Bb][Ee]-[Ff][Rr]|'
+ '[Ss][Gg][Nn]-[Bb][Ee]-[Nn][Ll]|[Ss][Gg][Nn]-'
+ '[Cc][Hh]-[Dd][Ee])|([Aa][Rr][Tt]-'
+ '[Ll][Oo][Jj][Bb][Aa][Nn]|[Cc][Ee][Ll]-'
+ '[Gg][Aa][Uu][Ll][Ii][Ss][Hh]|'
+ '[Nn][Oo]-[Bb][Oo][Kk]|[Nn][Oo]-'
+ '[Nn][Yy][Nn]|[Zz][Hh]-[Gg][Uu][Oo][Yy][Uu]|'
+ '[Zz][Hh]-[Hh][Aa][Kk][Kk][Aa]|[Zz][Hh]-'
+ '[Mm][Ii][Nn]|[Zz][Hh]-[Mm][Ii][Nn]-'
+ '[Nn][Aa][Nn]|[Zz][Hh]-[Xx][Ii][Aa][Nn][Gg])))';
}
default "en-US";
description
"Indicates the language tag that is used for
'attack-description'.";
reference
"RFC 5646: Tags for Identifying Languages, Section 2.1";
}
leaf last-updated {
type uint64;
mandatory true;
description
"The time the mapping table was updated. It is
represented in seconds relative to
1970-01-01T00:00:00Z.";
}
list attack-mapping {
key "attack-id";
description
"Attack mapping details.";
leaf attack-id {
type uint32;
description
"Unique identifier assigned by the vendor for the
attack.";
}
leaf attack-description {
type string;
mandatory true;
description
"Textual representation of the attack description.
Natural Language Processing techniques (e.g.,
word embedding) might provide some utility in
mapping the attack description to an attack type.";
}
}
}
}
augment "/data-channel:dots-data/data-channel:dots-client" {
if-feature "dots-telemetry";
description
"Augments the data channel with a vendor attack
mapping table of the DOTS client.";
container vendor-mapping {
description
"Used by DOTS clients to share their vendor
attack mapping information with DOTS servers.";
uses attack-mapping;
}
}
augment "/data-channel:dots-data/data-channel:capabilities" {
if-feature "dots-telemetry";
description
"Augments the DOTS server capabilities with a
parameter to indicate whether they can share
attack mapping details.";
leaf vendor-mapping-enabled {
type boolean;
config false;
description
"Indicates that the DOTS server supports sharing
attack vendor mapping details with DOTS clients.";
}
}
augment "/data-channel:dots-data" {
if-feature "dots-telemetry";
description
"Augments the data channel with a vendor attack
mapping table of the DOTS server.";
container vendor-mapping {
config false;
description
"Includes the list of vendor attack mapping details
that will be shared with DOTS clients upon request.";
uses attack-mapping;
}
}
}
<CODE ENDS>
12. YANG/JSON Mapping Parameters to CBOR
All DOTS telemetry parameters in the payload of the DOTS signal
channel MUST be mapped to CBOR types as shown in Table 3:
| Note: Implementers must check that the mapping output provided
| by their YANG-to-CBOR encoding schemes is aligned with the
| contents of Table 3.
+======================+==============+======+=============+========+
|Parameter Name |YANG Type |CBOR |CBOR Major | JSON |
| | |Key |Type & | Type |
| | | |Information | |
+======================+==============+======+=============+========+
|tsid |uint32 |128 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|telemetry |list |129 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|low-percentile |decimal64 |130 |6 tag 4 [-2, | String |
| | | |integer] | |
+----------------------+--------------+------+-------------+--------+
|mid-percentile |decimal64 |131 |6 tag 4 [-2, | String |
| | | |integer] | |
+----------------------+--------------+------+-------------+--------+
|high-percentile |decimal64 |132 |6 tag 4 [-2, | String |
| | | |integer] | |
+----------------------+--------------+------+-------------+--------+
|unit-config |list |133 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|unit |enumeration |134 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|unit-status |boolean |135 |7 bits 20 | False |
| | | +-------------+--------+
| | | |7 bits 21 | True |
+----------------------+--------------+------+-------------+--------+
|total-pipe-capacity |list |136 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|link-id |string |137 |3 text string| String |
+----------------------+--------------+------+-------------+--------+
|pre-or-ongoing- |list |138 |4 array | Array |
|mitigation | | | | |
+----------------------+--------------+------+-------------+--------+
|total-traffic-normal |list |139 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|low-percentile-g |yang:gauge64 |140 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|mid-percentile-g |yang:gauge64 |141 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|high-percentile-g |yang:gauge64 |142 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|peak-g |yang:gauge64 |143 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|total-attack-traffic |list |144 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|total-traffic |list |145 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|total-connection- |list |146 |4 array | Array |
|capacity | | | | |
+----------------------+--------------+------+-------------+--------+
|connection |uint64 |147 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|connection-client |uint64 |148 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|embryonic |uint64 |149 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|embryonic-client |uint64 |150 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|connection-ps |uint64 |151 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|connection-client-ps |uint64 |152 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|request-ps |uint64 |153 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|request-client-ps |uint64 |154 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|partial-request-max |uint64 |155 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|partial-request- |uint64 |156 |0 unsigned | String |
|client-max | | | | |
+----------------------+--------------+------+-------------+--------+
|total-attack- |container |157 |5 map | Object |
|connection | | | | |
+----------------------+--------------+------+-------------+--------+
|connection-c |container |158 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|embryonic-c |container |159 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|connection-ps-c |container |160 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|request-ps-c |container |161 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|attack-detail |list |162 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|id |uint32 |163 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|attack-id |uint32 |164 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|attack-description |string |165 |3 text string| String |
+----------------------+--------------+------+-------------+--------+
|attack-severity |enumeration |166 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|start-time |uint64 |167 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|end-time |uint64 |168 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|source-count |container |169 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|top-talker |container |170 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|spoofed-status |boolean |171 |7 bits 20 | False |
| | | +-------------+--------+
| | | |7 bits 21 | True |
+----------------------+--------------+------+-------------+--------+
|partial-request-c |container |172 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|total-attack- |list |173 |4 array | Array |
|connection-protocol | | | | |
+----------------------+--------------+------+-------------+--------+
|baseline |list |174 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|current-config |container |175 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|max-config-values |container |176 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|min-config-values |container |177 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|supported-unit-classes|container |178 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|server-originated- |boolean |179 |7 bits 20 | False |
|telemetry | | +-------------+--------+
| | | |7 bits 21 | True |
+----------------------+--------------+------+-------------+--------+
|telemetry-notify- |uint16 |180 |0 unsigned | Number |
|interval | | | | |
+----------------------+--------------+------+-------------+--------+
|tmid |uint32 |181 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|measurement-interval |enumeration |182 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|measurement-sample |enumeration |183 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|talker |list |184 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|source-prefix |inet:ip-prefix|185 |3 text string| String |
+----------------------+--------------+------+-------------+--------+
|mid-list |leaf-list |186 |4 array | Array |
| +--------------+------+-------------+--------+
| |uint32 | |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|source-port-range |list |187 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|source-icmp-type-range|list |188 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|target |container |189 |5 map | Object |
+----------------------+--------------+------+-------------+--------+
|capacity |uint64 |190 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|protocol |uint8 |191 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|total-traffic-normal- |list |192 |4 array | Array |
|per-protocol | | | | |
+----------------------+--------------+------+-------------+--------+
|total-traffic-normal- |list |193 |4 array | Array |
|per-port | | | | |
+----------------------+--------------+------+-------------+--------+
|total-connection- |list |194 |4 array | Array |
|capacity-per-port | | | | |
+----------------------+--------------+------+-------------+--------+
|total-traffic-protocol|list |195 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|total-traffic-port |list |196 |4 array | Array |
+----------------------+--------------+------+-------------+--------+
|total-attack-traffic- |list |197 |4 array | Array |
|protocol | | | | |
+----------------------+--------------+------+-------------+--------+
|total-attack-traffic- |list |198 |4 array | Array |
|port | | | | |
+----------------------+--------------+------+-------------+--------+
|total-attack- |list |199 |4 array | Array |
|connection-port | | | | |
+----------------------+--------------+------+-------------+--------+
|port |inet:port- |200 |0 unsigned | Number |
| |number | | | |
+----------------------+--------------+------+-------------+--------+
|supported-query-type |leaf-list |201 |4 array | Array |
| +--------------+------+-------------+--------+
| | | |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|vendor-id |uint32 |202 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|ietf-dots- |container |203 |5 map | Object |
|telemetry:telemetry- | | | | |
|setup | | | | |
+----------------------+--------------+------+-------------+--------+
|ietf-dots- |list |204 |4 array | Array |
|telemetry:total- | | | | |
|traffic | | | | |
+----------------------+--------------+------+-------------+--------+
|ietf-dots- |list |205 |4 array | Array |
|telemetry:total- | | | | |
|attack-traffic | | | | |
+----------------------+--------------+------+-------------+--------+
|ietf-dots- |container |206 |5 map | Object |
|telemetry:total- | | | | |
|attack-connection | | | | |
+----------------------+--------------+------+-------------+--------+
|ietf-dots- |list |207 |4 array | Array |
|telemetry:attack- | | | | |
|detail | | | | |
+----------------------+--------------+------+-------------+--------+
|ietf-dots- |container |208 |5 map | Object |
|telemetry:telemetry | | | | |
+----------------------+--------------+------+-------------+--------+
|current-g |yang:gauge64 |209 |0 unsigned | String |
+----------------------+--------------+------+-------------+--------+
|description-lang |string |210 |3 text string| String |
+----------------------+--------------+------+-------------+--------+
|lower-type |uint8 |32771 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
|upper-type |uint8 |32772 |0 unsigned | Number |
+----------------------+--------------+------+-------------+--------+
Table 3: YANG/JSON Mapping Parameters to CBOR
13. IANA Considerations
13.1. DOTS Signal Channel CBOR Key Values
This specification registers the following comprehension-optional
parameters in the IANA "DOTS Signal Channel CBOR Key Values" registry
[Key-Map].
+======================+==========+=======+============+===========+
| Parameter Name | CBOR Key | CBOR | Change | Reference |
| | Value | Major | Controller | |
| | | Type | | |
+======================+==========+=======+============+===========+
| tsid | 128 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| telemetry | 129 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| low-percentile | 130 | 6tag4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| mid-percentile | 131 | 6tag4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| high-percentile | 132 | 6tag4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| unit-config | 133 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| unit | 134 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| unit-status | 135 | 7 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| total-pipe-capacity | 136 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| link-id | 137 | 3 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| pre-or-ongoing- | 138 | 4 | IESG | RFC 9244 |
| mitigation | | | | |
+----------------------+----------+-------+------------+-----------+
| total-traffic-normal | 139 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| low-percentile-g | 140 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| mid-percentile-g | 141 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| high-percentile-g | 142 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| peak-g | 143 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| total-attack-traffic | 144 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| total-traffic | 145 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| total-connection- | 146 | 4 | IESG | RFC 9244 |
| capacity | | | | |
+----------------------+----------+-------+------------+-----------+
| connection | 147 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| connection-client | 148 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| embryonic | 149 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| embryonic-client | 150 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| connection-ps | 151 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| connection-client-ps | 152 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| request-ps | 153 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| request-client-ps | 154 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| partial-request-max | 155 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| partial-request- | 156 | 0 | IESG | RFC 9244 |
| client-max | | | | |
+----------------------+----------+-------+------------+-----------+
| total-attack- | 157 | 5 | IESG | RFC 9244 |
| connection | | | | |
+----------------------+----------+-------+------------+-----------+
| connection-c | 158 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| embryonic-c | 159 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| connection-ps-c | 160 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| request-ps-c | 161 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| attack-detail | 162 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| id | 163 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| attack-id | 164 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| attack-description | 165 | 3 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| attack-severity | 166 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| start-time | 167 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| end-time | 168 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| source-count | 169 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| top-talker | 170 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| spoofed-status | 171 | 7 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| partial-request-c | 172 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| total-attack- | 173 | 4 | IESG | RFC 9244 |
| connection-protocol | | | | |
+----------------------+----------+-------+------------+-----------+
| baseline | 174 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| current-config | 175 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| max-config-values | 176 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| min-config-values | 177 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| supported-unit- | 178 | 5 | IESG | RFC 9244 |
| classes | | | | |
+----------------------+----------+-------+------------+-----------+
| server-originated- | 179 | 7 | IESG | RFC 9244 |
| telemetry | | | | |
+----------------------+----------+-------+------------+-----------+
| telemetry-notify- | 180 | 0 | IESG | RFC 9244 |
| interval | | | | |
+----------------------+----------+-------+------------+-----------+
| tmid | 181 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| measurement-interval | 182 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| measurement-sample | 183 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| talker | 184 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| source-prefix | 185 | 3 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| mid-list | 186 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| source-port-range | 187 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| source-icmp-type- | 188 | 4 | IESG | RFC 9244 |
| range | | | | |
+----------------------+----------+-------+------------+-----------+
| target | 189 | 5 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| capacity | 190 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| protocol | 191 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| total-traffic- | 192 | 4 | IESG | RFC 9244 |
| normal-per-protocol | | | | |
+----------------------+----------+-------+------------+-----------+
| total-traffic- | 193 | 4 | IESG | RFC 9244 |
| normal-per-port | | | | |
+----------------------+----------+-------+------------+-----------+
| total-connection- | 194 | 4 | IESG | RFC 9244 |
| capacity-per-port | | | | |
+----------------------+----------+-------+------------+-----------+
| total-traffic- | 195 | 4 | IESG | RFC 9244 |
| protocol | | | | |
+----------------------+----------+-------+------------+-----------+
| total-traffic-port | 196 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| total-attack- | 197 | 4 | IESG | RFC 9244 |
| traffic-protocol | | | | |
+----------------------+----------+-------+------------+-----------+
| total-attack- | 198 | 4 | IESG | RFC 9244 |
| traffic-port | | | | |
+----------------------+----------+-------+------------+-----------+
| total-attack- | 199 | 4 | IESG | RFC 9244 |
| connection-port | | | | |
+----------------------+----------+-------+------------+-----------+
| port | 200 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| supported-query-type | 201 | 4 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| vendor-id | 202 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| ietf-dots- | 203 | 5 | IESG | RFC 9244 |
| telemetry:telemetry- | | | | |
| setup | | | | |
+----------------------+----------+-------+------------+-----------+
| ietf-dots- | 204 | 4 | IESG | RFC 9244 |
| telemetry:total- | | | | |
| traffic | | | | |
+----------------------+----------+-------+------------+-----------+
| ietf-dots- | 205 | 4 | IESG | RFC 9244 |
| telemetry:total- | | | | |
| attack-traffic | | | | |
+----------------------+----------+-------+------------+-----------+
| ietf-dots- | 206 | 5 | IESG | RFC 9244 |
| telemetry:total- | | | | |
| attack-connection | | | | |
+----------------------+----------+-------+------------+-----------+
| ietf-dots- | 207 | 4 | IESG | RFC 9244 |
| telemetry:attack- | | | | |
| detail | | | | |
+----------------------+----------+-------+------------+-----------+
| ietf-dots- | 208 | 5 | IESG | RFC 9244 |
| telemetry:telemetry | | | | |
+----------------------+----------+-------+------------+-----------+
| current-g | 209 | 0 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
| description-lang | 210 | 3 | IESG | RFC 9244 |
+----------------------+----------+-------+------------+-----------+
Table 4: Registered DOTS Signal Channel CBOR Key Values
13.2. DOTS Signal Channel Conflict Cause Codes
Per this document, IANA has assigned a new code from the "DOTS Signal
Channel Conflict Cause Codes" registry [Cause].
+======+===================+========================+===========+
| Code | Label | Description | Reference |
+======+===================+========================+===========+
| 5 | overlapping-pipes | Overlapping pipe scope | RFC 9244 |
+------+-------------------+------------------------+-----------+
Table 5: Registered DOTS Signal Channel Conflict Cause Code
13.3. DOTS Telemetry URIs and YANG Module Registrations
Per this document, IANA has registered the following URIs in the "ns"
subregistry within the "IETF XML Registry" [RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-dots-telemetry
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-dots-mapping
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
Per this document, IANA has registered the following YANG modules in
the "YANG Module Names" subregistry [RFC6020] within the "YANG
Parameters" registry.
Name: ietf-dots-telemetry
Namespace: urn:ietf:params:xml:ns:yang:ietf-dots-telemetry
Maintained by IANA: N
Prefix: dots-telemetry
Reference: RFC 9244
Name: ietf-dots-mapping
Namespace: urn:ietf:params:xml:ns:yang:ietf-dots-mapping
Maintained by IANA: N
Prefix: dots-mapping
Reference: RFC 9244
14. Security Considerations
14.1. DOTS Signal Channel Telemetry
The security considerations for the DOTS signal channel protocol are
discussed in Section 11 of [RFC9132]. The following discusses the
security considerations that are specific to the DOTS signal channel
extension defined in this document.
The DOTS telemetry information includes DOTS client network topology,
DOTS client domain pipe capacity, normal traffic baseline and
connection capacity, and threat and mitigation information. Such
information is sensitive; it MUST be protected at rest by the DOTS
server domain to prevent data leakage. Note that sharing this
sensitive data with a trusted DOTS server does not introduce any new
significant considerations other than the need for the aforementioned
protection. Such a DOTS server is already trusted to have access to
that kind of information by being in the position to observe and
mitigate attacks.
DOTS clients are typically considered to be trusted devices by the
DOTS client domain. DOTS clients may be co-located on network
security services (e.g., firewall devices), and a compromised
security service potentially can do a lot more damage to the network
than just the DOTS client component. This assumption differs from
the often-held view (often referred to as the "zero-trust model")
that devices are untrusted. A compromised DOTS client can send fake
DOTS telemetry data to a DOTS server to mislead the DOTS server.
This attack can be prevented by monitoring and auditing DOTS clients
to detect misbehavior and to deter misuse, and by only authorizing
the DOTS client to convey DOTS telemetry information for specific
target resources (e.g., an application server is authorized to
exchange DOTS telemetry for its IP addresses but a DDoS mitigator can
exchange DOTS telemetry for any target resource in the network). As
a reminder, this is a variation of dealing with compromised DOTS
clients as discussed in Section 11 of [RFC9132].
DOTS servers must be capable of defending themselves against DoS
attacks from compromised DOTS clients. The following non-
comprehensive list of mitigation techniques can be used by a DOTS
server to handle misbehaving DOTS clients:
* The probing rate (defined in Section 4.5 of [RFC9132]) can be used
to limit the average data rate to the DOTS server.
* Rate-limiting DOTS telemetry, including packets with new 'tmid'
values from the same DOTS client, defends against DoS attacks that
would result in varying the 'tmid' to exhaust DOTS server
resources. Likewise, the DOTS server can enforce a quota and time
limit on the number of active pre-or-ongoing-mitigation telemetry
data items (identified by 'tmid') from the DOTS client.
Note also that the telemetry notification interval may be used to
rate-limit the pre-or-ongoing-mitigation telemetry notifications
received by a DOTS client domain.
14.2. Vendor Attack Mapping
The security considerations for the DOTS data channel protocol are
discussed in Section 10 of [RFC8783]. The following discusses the
security considerations that are specific to the DOTS data channel
extension defined in this document.
All data nodes defined in the YANG module specified in Section 11.2
that can be created, modified, and deleted (i.e., config true, which
is the default) are considered sensitive. Write operations to these
data nodes without proper protection can have a negative effect on
network operations. Appropriate security measures are recommended to
prevent illegitimate users from invoking DOTS data channel primitives
as discussed in [RFC8783]. Nevertheless, an attacker who can access
a DOTS client is technically capable of undertaking various attacks,
such as:
* Communicating invalid attack mapping details to the server
('/data-channel:dots-data/data-channel:dots-client/dots-
telemetry:vendor-mapping'), which will mislead the server when
correlating attack details.
Some of the readable data nodes in the YANG module specified in
Section 11.2 may be considered sensitive. It is thus important to
control read access to these data nodes. These are the data nodes
and their sensitivity:
* '/data-channel:dots-data/data-channel:dots-client/dots-
telemetry:vendor-mapping' can be misused to infer the DDoS
protection technology deployed in a DOTS client domain.
* '/data-channel:dots-data/dots-telemetry:vendor-mapping' can be
used by a compromised DOTS client to leak the attack detection
capabilities of the DOTS server. This is a variation of the
compromised DOTS client attacks discussed in Section 14.1.
15. References
15.1. Normative References
[Private-Enterprise-Numbers]
IANA, "Private Enterprise Numbers",
<https://www.iana.org/assignments/enterprise-numbers/>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC5646] Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying
Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646,
September 2009, <https://www.rfc-editor.org/info/rfc5646>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7252] Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252,
DOI 10.17487/RFC7252, June 2014,
<https://www.rfc-editor.org/info/rfc7252>.
[RFC7641] Hartke, K., "Observing Resources in the Constrained
Application Protocol (CoAP)", RFC 7641,
DOI 10.17487/RFC7641, September 2015,
<https://www.rfc-editor.org/info/rfc7641>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC7959] Bormann, C. and Z. Shelby, Ed., "Block-Wise Transfers in
the Constrained Application Protocol (CoAP)", RFC 7959,
DOI 10.17487/RFC7959, August 2016,
<https://www.rfc-editor.org/info/rfc7959>.
[RFC7970] Danyliw, R., "The Incident Object Description Exchange
Format Version 2", RFC 7970, DOI 10.17487/RFC7970,
November 2016, <https://www.rfc-editor.org/info/rfc7970>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8345] Clemm, A., Medved, J., Varga, R., Bahadur, N.,
Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
2018, <https://www.rfc-editor.org/info/rfc8345>.
[RFC8783] Boucadair, M., Ed. and T. Reddy.K, Ed., "Distributed
Denial-of-Service Open Threat Signaling (DOTS) Data
Channel Specification", RFC 8783, DOI 10.17487/RFC8783,
May 2020, <https://www.rfc-editor.org/info/rfc8783>.
[RFC8791] Bierman, A., Björklund, M., and K. Watsen, "YANG Data
Structure Extensions", RFC 8791, DOI 10.17487/RFC8791,
June 2020, <https://www.rfc-editor.org/info/rfc8791>.
[RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", STD 94, RFC 8949,
DOI 10.17487/RFC8949, December 2020,
<https://www.rfc-editor.org/info/rfc8949>.
[RFC9132] Boucadair, M., Ed., Shallow, J., and T. Reddy.K,
"Distributed Denial-of-Service Open Threat Signaling
(DOTS) Signal Channel Specification", RFC 9132,
DOI 10.17487/RFC9132, September 2021,
<https://www.rfc-editor.org/info/rfc9132>.
15.2. Informative References
[Cause] IANA, "DOTS Signal Channel Conflict Cause Codes",
<https://www.iana.org/assignments/dots/>.
[DOTS-Multihoming]
Boucadair, M., Reddy.K, T., and W. Pan, "Multi-homing
Deployment Considerations for Distributed-Denial-of-
Service Open Threat Signaling (DOTS)", Work in Progress,
Internet-Draft, draft-ietf-dots-multihoming-13, 26 April
2022, <https://datatracker.ietf.org/doc/html/draft-ietf-
dots-multihoming-13>.
[DOTS-Robust-Blocks]
Boucadair, M. and J. Shallow, "Distributed Denial-of-
Service Open Threat Signaling (DOTS) Signal Channel
Configuration Attributes for Robust Block Transmission",
Work in Progress, Internet-Draft, draft-ietf-dots-robust-
blocks-03, 11 February 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-dots-
robust-blocks-03>.
[DOTS-Telemetry-Specs]
Doron, E., Reddy, T., Andreasen, F., Xia, L., and K.
Nishizuka, "Distributed Denial-of-Service Open Threat
Signaling (DOTS) Telemetry Specifications", Work in
Progress, Internet-Draft, draft-doron-dots-telemetry-00,
30 October 2016, <https://datatracker.ietf.org/doc/html/
draft-doron-dots-telemetry-00>.
[Key-Map] IANA, "DOTS Signal Channel CBOR Key Values",
<https://www.iana.org/assignments/dots/>.
[PYANG] "pyang", commit dad5c68, April 2022,
<https://github.com/mbj4668/pyang>.
[RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
"Framework for IP Performance Metrics", RFC 2330,
DOI 10.17487/RFC2330, May 1998,
<https://www.rfc-editor.org/info/rfc2330>.
[RFC4732] Handley, M., Ed., Rescorla, E., Ed., and IAB, "Internet
Denial-of-Service Considerations", RFC 4732,
DOI 10.17487/RFC4732, December 2006,
<https://www.rfc-editor.org/info/rfc4732>.
[RFC5612] Eronen, P. and D. Harrington, "Enterprise Number for
Documentation Use", RFC 5612, DOI 10.17487/RFC5612, August
2009, <https://www.rfc-editor.org/info/rfc5612>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8525] Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K.,
and R. Wilton, "YANG Library", RFC 8525,
DOI 10.17487/RFC8525, March 2019,
<https://www.rfc-editor.org/info/rfc8525>.
[RFC8612] Mortensen, A., Reddy, T., and R. Moskowitz, "DDoS Open
Threat Signaling (DOTS) Requirements", RFC 8612,
DOI 10.17487/RFC8612, May 2019,
<https://www.rfc-editor.org/info/rfc8612>.
[RFC8811] Mortensen, A., Ed., Reddy.K, T., Ed., Andreasen, F.,
Teague, N., and R. Compton, "DDoS Open Threat Signaling
(DOTS) Architecture", RFC 8811, DOI 10.17487/RFC8811,
August 2020, <https://www.rfc-editor.org/info/rfc8811>.
[RFC8903] Dobbins, R., Migault, D., Moskowitz, R., Teague, N., Xia,
L., and K. Nishizuka, "Use Cases for DDoS Open Threat
Signaling", RFC 8903, DOI 10.17487/RFC8903, May 2021,
<https://www.rfc-editor.org/info/rfc8903>.
[RFC9133] Nishizuka, K., Boucadair, M., Reddy.K, T., and T. Nagata,
"Controlling Filtering Rules Using Distributed Denial-of-
Service Open Threat Signaling (DOTS) Signal Channel",
RFC 9133, DOI 10.17487/RFC9133, September 2021,
<https://www.rfc-editor.org/info/rfc9133>.
[RFC9177] Boucadair, M. and J. Shallow, "Constrained Application
Protocol (CoAP) Block-Wise Transfer Options Supporting
Robust Transmission", RFC 9177, DOI 10.17487/RFC9177,
March 2022, <https://www.rfc-editor.org/info/rfc9177>.
[RFC9260] Stewart, R., Tüxen, M., and K. Nielsen, "Stream Control
Transmission Protocol", RFC 9260, DOI 10.17487/RFC9260,
June 2022, <https://www.rfc-editor.org/info/rfc9260>.
Acknowledgments
The authors would like to thank Flemming Andreasen, Liang Xia, and
Kaname Nishizuka, coauthors of [DOTS-Telemetry-Specs], and everyone
who had contributed to that document.
Thanks to Kaname Nishizuka, Yuhei Hayashi, and Tom Petch for comments
and review.
Special thanks to Jon Shallow and Kaname Nishizuka for their
implementation and interoperability work.
Many thanks to Jan Lindblad for the yangdoctors review, Nagendra
Nainar for the opsdir review, James Gruessing for the artart review,
Michael Scharf for the tsv-art review, Ted Lemon for the int-dir
review, and Robert Sparks for the gen-art review.
Thanks to Benjamin Kaduk for the detailed AD review.
Thanks to Roman Danyliw, Éric Vyncke, Francesca Palombini, Warren
Kumari, Erik Kline, Lars Eggert, and Robert Wilton for the IESG
review.
Contributors
The following individuals have contributed to this document:
Li Su
CMCC
Email: suli@chinamobile.com
Pan Wei
Huawei
Email: william.panwei@huawei.com
Authors' Addresses
Mohamed Boucadair (editor)
Orange
35000 Rennes
France
Email: mohamed.boucadair@orange.com
Tirumaleswar Reddy.K (editor)
Akamai
Embassy Golf Link Business Park
Bangalore 560071
Karnataka
India
Email: kondtir@gmail.com
Ehud Doron
Radware Ltd.
Raoul Wallenberg Street
Tel-Aviv 69710
Israel
Email: ehudd@radware.com
Meiling Chen
CMCC
32 Xuanwumen West Street
Beijing
100053
China
Email: chenmeiling@chinamobile.com
Jon Shallow
United Kingdom
Email: supjps-ietf@jpshallow.com