Internet Engineering Task Force (IETF) D. Eastlake 3rd
Request for Comments: 7042 Huawei
BCP: 141 J. Abley
Obsoletes: 5342 Dyn, Inc.
Updates: 2153 October 2013
Category: Best Current Practice
ISSN: 2070-1721
IANA Considerations and IETF Protocol and Documentation Usage
for IEEE 802 Parameters
Abstract
Some IETF protocols make use of Ethernet frame formats and IEEE 802
parameters. This document discusses several uses of such parameters
in IETF protocols, specifies IANA considerations for assignment of
points under the IANA OUI (Organizationally Unique Identifier), and
provides some values for use in documentation. This document
obsoletes RFC 5342.
Status of This Memo
This memo documents an Internet Best Current Practice.
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
BCPs is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc7042.
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RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
Copyright Notice
Copyright (c) 2013 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
(http://trustee.ietf.org/license-info) in effect on the date of
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include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
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Table of Contents
1. Introduction ....................................................4
1.1. Notations Used in This Document ............................4
1.2. Changes from RFC 5342 ......................................5
1.3. The IEEE Registration Authority ............................5
1.4. The IANA OUI ...............................................5
2. Ethernet Identifier Parameters ..................................5
2.1. 48-Bit MAC Identifiers, OUIs, and Other Prefixes ...........6
2.1.1. EUI-48 Assignments under the IANA OUI ...............6
2.1.2. EUI-48 Documentation Values .........................7
2.1.3. EUI-48 IANA Assignment Considerations ...............8
2.2. 64-Bit MAC Identifiers .....................................8
2.2.1. IPv6 Use of Modified EUI-64 Identifiers .............9
2.2.2. EUI-64 IANA Assignment Considerations ..............10
2.2.3. EUI-64 Documentation Values ........................12
2.3. Other MAC-48 Identifiers Used by the IETF .................12
2.3.1. Identifiers Prefixed "33-33" .......................12
2.3.2. The 'CF Series' ....................................13
2.3.2.1. Changes to RFC 2153 .......................13
3. Ethernet Protocol Parameters ...................................14
3.1. Ethernet Protocol Assignment under the IANA OUI ...........16
3.2. Documentation Protocol Number .............................16
4. Other OUI-Based Parameters .....................................16
5. IANA Considerations ............................................17
5.1. Expert Review and IESG Ratification .......................17
5.2. MAC Address AFNs and RRTYPEs ..............................19
5.3. Informational IANA Web Page Material ......................19
5.4. OUI Exhaustion ............................................19
5.5. IANA OUI MAC Address Table ................................19
5.6. SNAP Protocol Number Table and Assignment .................20
6. Security Considerations ........................................20
7. Acknowledgements ...............................................20
8. References .....................................................21
8.1. Normative References ......................................21
8.2. Informative References ....................................21
Appendix A. Templates .............................................24
A.1. EUI-48/EUI-64 Identifier or Identifier Block Template .....24
A.2. IANA OUI-Based Protocol Number Template ...................24
A.3. Other IANA OUI-Based Parameter Template ...................25
Appendix B. Ethertypes ............................................25
B.1. Some Ethertypes Specified by the IETF .....................25
B.2. Some IEEE 802 Ethertypes ..................................26
Appendix C. Documentation Protocol Number .........................26
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1. Introduction
Some IETF protocols use Ethernet or other IEEE 802-related
communication frame formats and parameters [IEEE802]. These include
MAC (Media Access Control) identifiers and protocol identifiers.
This document specifies IANA considerations for the assignment of
code points under the IANA OUI. It also discusses several other uses
by the IETF of IEEE 802 code points and provides some values for use
in documentation. As noted in [RFC2606] and [RFC5737], the use of
designated code values reserved for documentation and examples
reduces the likelihood of conflicts and confusion arising from their
duplication of code points assigned for some deployed use.
[RFC5226] is incorporated herein except where there are contrary
provisions in this document. In this document, "IESG Ratification"
is used in some cases, and it is specified in Section 5.1. This is
not the same as "IESG Approval" in [RFC5226].
1.1. Notations Used in This Document
This document uses hexadecimal notation. Each octet (that is, 8-bit
byte) is represented by two hexadecimal digits giving the value of
the octet as an unsigned integer. Successive octets are separated by
a hyphen. This document consistently uses IETF bit ordering although
the physical order of bit transmission within an octet on an IEEE
[802.3] link is from the lowest order bit to the highest order bit
(i.e., the reverse of the IETF's ordering).
In this document:
"AFN" stands for Address Family Number [RFC4760].
"EUI" stands for Extended Unique Identifier.
"IAB" stands for Individual Address Block, not for Internet
Architecture Board.
"MAC" stands for Media Access Control, not for Message
Authentication Code.
"OUI" stands for Organizationally Unique Identifier.
"RRTYPE" stands for a DNS Resource Record type [RFC6895].
"**" indicates exponentiation. For example, 2**24 is two to the
twenty-fourth power.
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1.2. Changes from RFC 5342
o Added MAC addresses and IANA OUI-based protocol and other values
for use in documentation, and added relevant Security
Considerations language.
o Eliminated any requirements for parallel unicast and multicast
assignment unless requested. Such requirements had been included
in [RFC5342] on the theory they would make bookkeeping easier for
IANA but they have proved to be problematic in practice.
o Re-casted informational material about relevant IEEE assignment
policies to take into account [RAC-OUI].
o Added AFNs and RRTYPEs for 48-bit and 64-bit MACs.
1.3. The IEEE Registration Authority
Originally the responsibility of Xerox Corporation, the registration
authority for Ethernet parameters is now the IEEE Registration
Authority, available on the web at:
http://standards.ieee.org/regauth/
Anyone may apply to that Authority for parameters. They may impose
fees or other requirements but commonly waive fees for applications
from standards development organizations.
A list of some assignments and their holders is downloadable from the
IEEE Registration Authority site.
1.4. The IANA OUI
The OUI 00-00-5E has been assigned to IANA.
There is no OUI value reserved at this time for documentation, but
there are documentation code points under the IANA OUI specified
below.
2. Ethernet Identifier Parameters
Section 2.1 discusses EUI-48 (Extended Unique Identifier 48) MAC
identifiers, their relationship to OUIs and other prefixes, and
assignments under the IANA OUI. Section 2.2 extends this to EUI-64
identifiers. Section 2.3 discusses other IETF MAC identifier use not
under the IANA OUI.
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[RAC-OUI] indicates that the IEEE Registration Authority Committee is
exploring the feasibility of defining a new "EUI-128" identifier.
2.1. 48-Bit MAC Identifiers, OUIs, and Other Prefixes
48-bit MAC "addresses" are the most commonly used Ethernet interface
identifiers. Those that are globally unique are also called EUI-48
identifiers. An EUI-48 is structured into an initial 3-octet OUI
(Organizationally Unique Identifier) and an additional 3 octets
assigned by the OUI holder or into a larger initial prefix assigned
to an organization and a shorter sequence of additional bits so as to
add up to 48 bits in total. For example, the IEEE has assigned IABs
(Individual Address Blocks), where the first 4 1/2 octets (36 bits)
are assigned, giving the holder of the IAB 1 1/2 octets (12 bits)
they can control; however, IABs will become historic, and a wider
range of prefix lengths will be made available [RAC-OUI].
The IEEE describes its assignment procedures and policies for IEEE
802-related identifiers in [802_O&A], which is being revised.
Two bits within the initial octet of an EUI-48 have special
significance in MAC addresses: the Group bit (01) and the Local bit
(02). OUIs and longer MAC prefixes are assigned with the Local bit
zero and the Group bit unspecified. Multicast identifiers may be
constructed by turning on the Group bit, and unicast identifiers may
be constructed by leaving the Group bit zero.
The Local bit is zero for globally unique EUI-48 identifiers assigned
by the owner of an OUI or owner of a longer prefix. If the Local bit
is a one, the identifier has been considered by IEEE 802 to be a
local identifier under the control of the local network
administrator; however, there may be emerging recommendations from
the IEEE Registration Authority on management of the local address
space. If the Local bit is on, the holder of an OUI has no special
authority over MAC identifiers whose first 3 octets correspond to
their OUI.
An AFN and a DNS RRTYPE have been assigned for 48-bit MAC addresses
(see Section 5.2).
2.1.1. EUI-48 Assignments under the IANA OUI
The OUI 00-00-5E has been assigned to IANA as stated in Section 1.4
above. This includes 2**24 EUI-48 multicast identifiers from
01-00-5E-00-00-00 to 01-00-5E-FF-FF-FF and 2**24 EUI-48 unicast
identifiers from 00-00-5E-00-00-00 to 00-00-5E-FF-FF-FF.
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Of these EUI-48 identifiers, the sub-blocks reserved or thus far
assigned by IANA for purposes of documentation are as follows:
Unicast, all blocks of 2**8 addresses thus far:
00-00-5E-00-00-00 through 00-00-5E-00-00-FF: reserved and require
IESG Ratification for assignment (see Section 5.1).
00-00-5E-00-01-00 through 00-00-5E-00-01-FF: assigned for the
Virtual Router Redundancy Protocol (VRRP) [RFC5798].
00-00-5E-00-02-00 through 00-00-5E-00-02-FF: assigned for the IPv6
Virtual Router Redundancy Protocol (IPv6 VRRP) [RFC5798].
00-00-5E-00-52-00 through 00-00-5E-00-52-FF: used for very small
assignments. Currently, 3 out of these 256 values have been
assigned.
00-00-5E-00-53-00 through 00-00-5E-00-53-FF: assigned for use in
documentation.
Multicast:
01-00-5E-00-00-00 through 01-00-5E-7F-FF-FF: 2**23 addresses
assigned for IPv4 multicast [RFC1112].
01-00-5E-80-00-00 through 01-00-5E-8F-FF-FF: 2**20 addresses
assigned for MPLS multicast [RFC5332].
01-00-5E-90-00-00 through 01-00-5E-90-00-FF: 2**8 addresses being
used for very small assignments. Currently, 4 out of these 256
values have been assigned.
01-00-5E-90-10-00 through 01-00-5E-90-10-FF: 2**8 addresses for
use in documentation.
For more detailed and up-to-date information, see the "Ethernet
Numbers" registry at http://www.iana.org.
2.1.2. EUI-48 Documentation Values
The following values have been assigned for use in documentation:
00-00-5E-00-53-00 through 00-00-5E-00-53-FF for unicast and
01-00-5E-90-10-00 through 01-00-5E-90-10-FF for multicast.
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2.1.3. EUI-48 IANA Assignment Considerations
EUI-48 assignments under the current or a future IANA OUI (see
Section 5.4) must meet the following requirements:
o must be for standards purposes (either for an IETF Standard or
other standard related to IETF work),
o must be for a power-of-two size block of identifiers starting
at a boundary that is an equal or greater power of two,
including the assignment of one (2**0) identifier,
o must not be used to evade the requirement for vendors to obtain
their own block of identifiers from the IEEE, and
o must be documented in an Internet-Draft or RFC.
In addition, approval must be obtained as follows (see the procedure
in Section 5.1):
Small to medium assignments of a block of 1, 2, 4, ..., 32768,
65536 (2**0, 2**1, 2**2, ..., 2**15, 2**16) EUI-48 identifiers
require Expert Review (see Section 5.1).
Large assignments of 131072 (2**17) or more EUI-48 identifiers
require IESG Ratification (see Section 5.1).
([RFC5342] had a requirement for parallel unicast and multicast
assignments under some circumstances even when one of the types was
not included in the application. That requirement has proved
impractical and is eliminated in this document.)
2.2. 64-Bit MAC Identifiers
IEEE also defines a system of 64-bit MAC identifiers including
EUI-64s. EUI-64 identifiers are currently used as follows:
o In a modified form to construct some IPv6 interface identifiers
as described in Section 2.2.1
o In IEEE Std 1394 (also known as FireWire and i.Link)
o In IEEE Std 802.15.4 (also known as ZigBee)
o In [InfiniBand]
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Adding a 5-octet (40-bit) extension to a 3-octet (24-bit) OUI, or a
shorter extension to longer assigned prefixes [RAC-OUI] so as to
total 64 bits, produces an EUI-64 identifier under that OUI or longer
prefix. As with EUI-48 identifiers, the first octet has the same
Group and Local bits.
An AFN and a DNS RRTYPE have been assigned for 64-bit MAC addresses
(see Section 5.2).
The discussion below is almost entirely in terms of the "Modified"
form of EUI-64 identifiers; however, anyone assigned such an
identifier can also use the unmodified form as a MAC identifier on
any link that uses such 64-bit identifiers for interfaces.
2.2.1. IPv6 Use of Modified EUI-64 Identifiers
MAC-64 identifiers are used to form the lower 64 bits of some IPv6
addresses (Section 2.5.1 and Appendix A of [RFC4291] and Appendix A
of [RFC5214]). When so used, the MAC-64 is modified by inverting the
Local/Global bit to form an IETF "Modified EUI-64 identifier". Below
is an illustration of a Modified EUI-64 unicast identifier under the
IANA OUI, where aa-bb-cc-dd-ee is the extension.
02-00-5E-aa-bb-cc-dd-ee
The first octet is shown as 02 rather than 00 because, in Modified
EUI-64 identifiers, the sense of the Local/Global bit is inverted
compared with EUI-48 identifiers. It is the globally unique values
(universal scope) that have the 02 bit on in the first octet, while
those with this bit off are locally assigned and out of scope for
global assignment.
The Local/Global bit was inverted to make it easier for network
operators to type in local-scope identifiers. Thus, such Modified
EUI-64 identifiers as 1, 2, etc. (ignoring leading zeros) are local.
Without the modification, they would have to be
02-00-00-00-00-00-00-01, 02-00-00-00-00-00-00-02, etc. to be local.
As with MAC-48 identifiers, the 01 bit on in the first octet
indicates a group identifier.
When the first two octets of the extension of a Modified EUI-64
identifier are FF-FE, the remainder of the extension is a 24-bit
value as assigned by the OUI owner for an EUI-48. For example:
02-00-5E-FF-FE-yy-yy-yy
or
03-00-5E-FF-FE-yy-yy-yy
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where yy-yy-yy is the portion (of an EUI-48 global unicast or
multicast identifier) that is assigned by the OUI owner (IANA in this
case). Thus, any holder of one or more EUI-48 identifiers under the
IANA OUI also has an equal number of Modified EUI-64 identifiers that
can be formed by inserting FF-FE in the middle of their EUI-48
identifiers and inverting the Local/Global bit.
(Note: [EUI-64] defines FF-FF as the bits to be inserted to create
an IEEE EUI-64 identifier from a MAC-48 identifier. That document
says the FF-FE value is used when starting with an EUI-48
identifier. The IETF uses only FF-FE to create Modified EUI-64
identifiers from 48-bit Ethernet station identifiers regardless of
whether they are EUI-48 or MAC-48 local identifiers. EUI-48 and
local MAC-48 identifiers are syntactically equivalent, and this
doesn't cause any problems in practice.)
In addition, certain Modified EUI-64 identifiers under the IANA OUI
are reserved for holders of IPv4 addresses as follows:
02-00-5E-FE-xx-xx-xx-xx
where xx-xx-xx-xx is a 32-bit IPv4 address. The owner of an IPv4
address has both the unicast- and multicast-derived EUI-64 address.
Modified EUI-64 identifiers from
02-00-5E-FE-F0-00-00-00 to 02-00-5E-FE-FF-FF-FF-FF
are effectively reserved pending the specification of IPv4 Class E
addresses. However, for Modified EUI-64 identifiers based on an IPv4
address, the Local/Global bit should be set to correspond to whether
the IPv4 address is local or global. (Keep in mind that the sense of
the Modified EUI-64 identifier Local/Global bit is reversed from that
in (unmodified) MAC-64 identifiers.)
2.2.2. EUI-64 IANA Assignment Considerations
The following table shows which Modified EUI-64 identifiers under the
IANA OUI are reserved, assigned, or available as indicated. As noted
above, the corresponding MAC addresses can be determined by
complementing the 02 bit in the first octet. In all cases, the
corresponding multicast 64-bit MAC addresses formed by complementing
the 01 bit in the first octet have the same status as the modified
64-bit unicast address blocks listed below.
02-00-5E-00-00-00-00-00 to 02-00-5E-0F-FF-FF-FF-FF reserved
02-00-5E-10-00-00-00-00 to 02-00-5E-10-00-00-00-FF assigned for
documentation use
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02-00-5E-10-00-00-01-00 to 02-00-5E-EF-FF-FF-FF-FF, which is
available for assignment
02-00-5E-F0-00-00-00-00 to 02-00-5E-FD-FF-FF-FF-FF reserved
02-00-5E-FE-00-00-00-00 to 02-00-5E-FE-FF-FF-FF-FF assigned to
IPv4 address holders as described above
02-00-5E-FF-00-00-00-00 to 02-00-5E-FF-FD-FF-FF-FF reserved
02-00-5E-FF-FE-00-00-00 to 02-00-5E-FF-FE-FF-FF-FF assigned for
holders of EUI-48 identifiers under the IANA OUI as described
above
02-00-5E-FF-FF-00-00-00 to 02-00-5E-FF-FF-FF-FF-FF reserved
The reserved identifiers above require IESG Ratification (see
Section 5.1) for assignment. IANA EUI-64 identifier assignments
under the IANA OUI must meet the following requirements:
o must be for standards purposes (either for an IETF Standard or
other standard related to IETF work),
o must be for a power-of-two size block of identifiers starting
at a boundary that is an equal or greater power of two,
including the assignment of one (2**0) identifier,
o must not be used to evade the requirement for vendors to obtain
their own block of identifiers from the IEEE, and
o must be documented in an Internet-Draft or RFC.
In addition, approval must be obtained as follows (see the procedure
in Section 5.1):
Small to medium assignments of a block of 1, 2, 4, ..., 134217728,
268435456 (2**0, 2**1, 2**2, ..., 2**27, 2**28) EUI-64
identifiers require Expert Review (see Section 5.1).
Assignments of any size, including 536870912 (2**29) or more
EUI-64 identifiers, may be made with IESG Ratification (see
Section 5.1).
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2.2.3. EUI-64 Documentation Values
The following blocks of unmodified 64-bit MAC addresses are for
documentation use. The IPv4-derived addresses are based on the IPv4
documentation addresses [RFC5737], and the MAC-derived addresses are
based on the EUI-48 documentation addresses above.
Unicast:
00-00-5E-EF-10-00-00-00 to 00-00-5E-EF-10-00-00-FF general
00-00-5E-FE-C0-00-02-00 to 00-00-5E-FE-C0-00-02-FF and
00-00-5E-FE-C6-33-64-00 to 00-00-5E-FE-C6-33-64-FF and
00-00-5E-FE-CB-00-71-00 to 00-00-5E-FE-CB-00-71-FF IPv4 derived
00-00-5E-FF-FE-00-53-00 to 00-00-5E-FF-FE-00-53-FF EUI-48 derived
00-00-5E-FE-EA-C0-00-02 and
00-00-5E-FE-EA-C6-33-64 and
00-00-5E-FE-EA-CB-00-71 IPv4 multicast derived from IPv4 unicast
[RFC6034]
Multicast:
01-00-5E-EF-10-00-00-00 to 01-00-5E-EF-10-00-00-FF general
01-00-5E-FE-C0-00-02-00 to 01-00-5E-FE-C0-00-02-FF and
01-00-5E-FE-C6-33-64-00 to 01-00-5E-FE-C6-33-64-FF and
01-00-5E-FE-CB-00-71-00 to 01-00-5E-FE-CB-00-71-FF IPv4 derived
01-00-5E-FE-EA-C0-00-02 and
01-00-5E-FE-EA-C6-33-64 and
01-00-5E-FE-EA-CB-00-71 IPv4 multicast derived from IPv4 unicast
[RFC6034]
01-00-5E-FF-FE-90-10-00 to 01-00-5E-FF-FE-90-10-FF EUI-48 derived
2.3. Other MAC-48 Identifiers Used by the IETF
There are two other blocks of MAC-48 identifiers that are used by the
IETF as described below.
2.3.1. Identifiers Prefixed "33-33"
All MAC-48 multicast identifiers prefixed "33-33" (that is, the 2**32
multicast MAC identifiers in the range from 33-33-00-00-00-00 to
33-33-FF-FF-FF-FF) are used as specified in [RFC2464] for IPv6
multicast. In all of these identifiers, the Group bit (the bottom
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bit of the first octet) is on, as is required to work properly with
existing hardware as a multicast identifier. They also have the
Local bit on and are used for this purpose in IPv6 networks.
(Historical note: It was the custom during IPv6 design to use "3"
for unknown or example values, and 3333 Coyote Hill Road, Palo
Alto, California, is the address of PARC (Palo Alto Research
Center, formerly "Xerox PARC"). Ethernet was originally specified
by the Digital Equipment Corporation, Intel Corporation, and Xerox
Corporation. The pre-IEEE [802.3] Ethernet protocol has sometimes
been known as "DIX" Ethernet from the first letters of the names
of these companies.)
2.3.2. The 'CF Series'
The Informational [RFC2153] declared the 3-octet values from CF-00-00
through CF-FF-FF to be OUIs available for assignment by IANA to
software vendors for use in PPP [RFC1661] or for other uses where
vendors do not otherwise need an IEEE-assigned OUI. It should be
noted that, when used as MAC-48 prefixes, these values have the Local
and Group bits on, while all IEEE-assigned OUIs thus far have those
bits off. The Group bit is meaningless in PPP. To quote [RFC2153]:
"The 'CF0000' series was arbitrarily chosen to match the PPP NLPID
'CF', as a matter of mnemonic convenience."
CF-00-00 is reserved, and IANA lists multicast identifier
CF-00-00-00-00-00 as used for Ethernet loopback tests.
In over a decade of availability, only a handful of values in the
'CF Series' have been assigned. (See "Ethernet Numbers"
<http://www.iana.org/assignments/ethernet-numbers> and "PPP Numbers"
<http://www.iana.org/assignments/ppp-numbers>).
2.3.2.1. Changes to RFC 2153
The IANA Considerations in [RFC2153] were updated as follows by the
approval of [RFC5342] (no technical changes were made at that time):
o Use of these identifiers based on IANA assignment was
deprecated.
o IANA was instructed not to assign any further values in the
'CF Series'.
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3. Ethernet Protocol Parameters
Ethernet protocol parameters provide a means of indicating the
contents of a frame -- for example, that its contents are IPv4 or
IPv6.
The concept has been extended to labeling by "tags". A tag in this
sense is a prefix whose type is identified by an Ethertype that is
then followed by either another tag, an Ethertype, or an LSAP (Link-
Layer Service Access Point) protocol indicator for the "main" body of
the frame, as described below. Traditionally, in the [802_O&A]
world, tags are a fixed length and do not include any encoding of
their own length. Any device that is processing a frame cannot, in
general, safely process anything in the frame past an Ethertype it
does not understand. An example is the C-Tag (formerly the Q-Tag)
[802.1Q]. It provides customer VLAN and priority information for a
frame.
There are two types of protocol identifier parameters that can occur
in Ethernet frames after the initial MAC-48 destination and source
identifiers:
Ethertypes: These are 16-bit identifiers appearing as the initial
two octets after the MAC destination and source (or after a
tag), which, when considered as an unsigned integer, are equal
to or larger than 0x0600.
LSAPs: These are 8-bit protocol identifiers that occur in pairs
immediately after an initial 16-bit (two-octet) remaining frame
length, which is in turn after the MAC destination and source
(or after a tag). Such a length must, when considered as an
unsigned integer, be less than 0x5DC, or it could be mistaken
as an Ethertype. LSAPs occur in pairs where one is intended to
indicate the source protocol handler and one the destination
protocol handler; however, use cases where the two are
different have been relatively rare.
Neither Ethertypes nor LSAPs are assigned by IANA; they are assigned
by the IEEE Registration Authority (see Section 1.3 above and
Appendix B). However, both LSAPs and Ethertypes have extension
mechanisms so that they can be used with five-octet Ethernet protocol
identifiers under an OUI, including those assigned by IANA under the
IANA OUI.
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When using the IEEE 802 Logical Link Control (LLC) format (Subnetwork
Access Protocol (SNAP)) [802_O&A] for a frame, an OUI-based protocol
identifier can be expressed as follows:
xx-xx-AA-AA-03-yy-yy-yy-zz-zz
where xx-xx is the frame length and, as above, must be small enough
not to be confused with an Ethertype; "AA" is the LSAP that indicates
this use and is sometimes referred to as the SNAP Service Access
Point (SAP); "03" is the LLC control octet indicating datagram
service; yy-yy-yy is an OUI; and zz-zz is a protocol number, under
that OUI, assigned by the OUI owner. The odd five-octet length for
such OUI-based protocol identifiers was chosen so that, with the LLC
control octet ("03"), the result is 16-bit aligned.
When using an Ethertype to indicate the main type for a frame body,
the special "OUI Extended Ethertype" 88-B7 is available. Using this
Ethertype, a frame body can begin with
88-B7-yy-yy-yy-zz-zz
where yy-yy-yy and zz-zz have the same meaning as in the SNAP format
described above.
It is also possible, within the SNAP format, to use an arbitrary
Ethertype. Putting the Ethertype as the zz-zz field after an all-
zeros OUI (00-00-00) does this. It looks like
xx-xx-AA-AA-03-00-00-00-zz-zz
where zz-zz is the Ethertype.
(Note that, at this point, the 802 protocol syntax facilities are
sufficiently powerful that they could be chained indefinitely.
Whether support for such chaining is generally required is not
clear, but [802_O&A] requires support for
xx-xx-AA-AA-03-00-00-00-88-B7-yy-yy-yy-zz-zz
although this could be more efficiently expressed by simply
pinching out the "00-00-00-88-B7" in the middle.)
As well as labeling frame contents, 802 protocol types appear within
NBMA (Non-Broadcast Multi-Access) Next Hop Resolution Protocol
[RFC2332] messages. Such messages have provisions for both two-octet
Ethertypes and OUI-based protocol types.
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3.1. Ethernet Protocol Assignment under the IANA OUI
Two-octet protocol numbers under the IANA OUI are available, as in
xx-xx-AA-AA-03-00-00-5E-qq-qq
where qq-qq is the protocol number.
A number of such assignments have been made out of the 2**16 protocol
numbers available from 00-00-5E-00-00 to 00-00-5E-FF-FF (see [IANA]).
The extreme values of this range, 00-00-5E-00-00 and 00-00-5E-FF-FF,
are reserved and require IESG Ratification for assignment (see
Section 5.1). New assignments of SNAP SAP protocol (qq-qq) numbers
under the IANA OUI must meet the following requirements:
o the assignment must be for standards use (either for an IETF
Standard or other standard related to IETF work),
o it must be documented in an Internet-Draft or RFC, and
o such protocol numbers are not to be assigned for any protocol
that has an Ethertype (because that can be expressed by putting
an all-zeros "OUI" before the Ethertype as described above).
In addition, the Expert Review (or IESG Ratification for the two
reserved values) must be obtained using the procedure specified in
Section 5.1.
3.2. Documentation Protocol Number
0x0042 is a protocol number under the IANA OUI (that is,
00-00-5E-00-42) to be used for documentation purposes.
4. Other OUI-Based Parameters
Some IEEE 802 and other protocols provide for parameters based on an
OUI beyond those discussed above. Such parameters most commonly
consist of an OUI plus one octet of additional value. They are
usually called "vendor specific" parameters, although "organization
specific" might be more accurate. They would look like
yy-yy-yy-zz
where yy-yy-yy is the OUI and zz is the additional specifier. An
example is the Cipher Suite Selector in IEEE [802.11].
Values may be assigned under the IANA OUI for such other OUI-based
parameter usage by Expert Review except that, for each use, the
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additional specifier values consisting of all zero bits and all one
bits (0x00 (00-00-5E-00) and 0xFF (00-00-5E-FF) for a one-octet
specifier) are reserved and require IESG Ratification (see
Section 5.1) for assignment; also, the additional specifier value
0x42 (00-00-5E-42) is assigned for use in documentation.
Assignments of such other IANA OUI-based parameters must be for
standards use (either for an IETF Standard or other standard related
to IETF work) and be documented in an Internet-Draft or RFC. The
first time a value is assigned for a particular parameter of this
type, an IANA registry will be created to contain that assignment and
any subsequent assignments of values for that parameter under the
IANA OUI. The Expert will specify the name of the registry.
If different policies from those above are required for such a
parameter, a BCP or Standards Track RFC must be adopted to update
this BCP and specify the new policy and parameter.
5. IANA Considerations
The entirety of this document concerns IANA considerations for the
assignment of Ethernet parameters in connection with the IANA OUI and
related matters.
As this document replaces [RFC5342], references to [RFC5342] in IANA
registries have been replaced by references to this document. In
addition, any references in the registries to [DOC-ADDR], which has
been combined into this document, have been replaced by references to
this document.
This document does not create any new IANA registries.
This document assigns MAC address values for documentation. These
values had been previously assigned by [DOC-ADDR]; as noted above,
any references in the registries to [DOC-ADDR] have been replaced by
references to this document.
The only other assignment that has been made by this document is a
protocol number for documentation. See Section 5.6 for details.
No existing assignment is changed by this document.
5.1. Expert Review and IESG Ratification
This section specifies the procedure for Expert Review and IESG
Ratification of MAC, protocol, and other IANA OUI-based identifiers.
The Expert(s) referred to in this document shall consist of one or
more persons appointed by and serving at the pleasure of the IESG.
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RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
The procedure described for Expert Review assignments in this
document is fully consistent with the IANA Expert Review policy
described in [RFC5226].
While finite, the universe of code points from which Expert-judged
assignments will be made is felt to be large enough that the
requirements given in this document and the Experts' good judgment
are sufficient guidance. The idea is for the Expert to provide a
light sanity check for small assignments of EUI identifiers, with
increased scrutiny by the Expert for medium-sized assignments of EUI
identifiers and assignments of protocol identifiers and other IANA
OUI-based parameters. However, it can make sense to assign very
large portions of the MAC identifier code point space. (Note that
existing assignments include one for 1/2 of the entire multicast IANA
EUI-48 code point space and one for 1/16 of that multicast code point
space.) In those cases, and in cases of the assignment of "reserved"
values, IESG Ratification of an Expert Review approval recommendation
is required as described below. The procedure is as follows:
The applicant always completes the appropriate template from
Appendix A below and sends it to IANA <iana@iana.org>.
IANA always sends the template to an appointed Expert. If the
Expert recuses themselves or is non-responsive, IANA may choose
an alternative appointed Expert or, if none is available, will
contact the IESG.
In all cases, if IANA receives a disapproval from an Expert
selected to review an application template, the application
will be denied.
If the assignment is based on Expert Review:
If IANA receives approval and code points are available,
IANA will make the requested assignment.
If the assignment is based on IESG Ratification:
The procedure starts with the first steps above for Expert
Review. If the Expert disapproves the application, they
simply inform IANA; however, if the Expert believes the
application should be approved, or is uncertain and believes
that the circumstances warrant the attention of the IESG,
the Expert will inform IANA about their advice, and IANA
will forward the application, together with the reasons for
approval or uncertainty, to the IESG. The IESG must decide
whether the assignment will be granted. This can be
accomplished by a management item in an IESG telechat as is
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RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
done for other types of requests. If the IESG decides not
to ratify a favorable opinion by the Expert or decides
against an application where the Expert is uncertain, the
application is denied; otherwise, it is granted. The IESG
will communicate its decision to the Expert and to IANA.
5.2. MAC Address AFNs and RRTYPEs
IANA has assigned Address Family Numbers (AFNs) for MAC addresses as
follows:
AFN Decimal Hex Reference
---------- ------- ------ ---------
48-bit MAC 16389 0x4005 [RFC7042]
64-bit MAC 16390 0x4006 [RFC7042]
IANA has assigned DNS RRTYPEs [RFC6895] for MAC addresses as follows:
RRTYPE Code
Data Mnemonic Decimal Hex Reference
---------- -------- ------- ------ -----------
48-bit MAC EUI48 108 0x006C [RFC7043]
64-bit MAC EUI64 109 0x006D [RFC7043]
5.3. Informational IANA Web Page Material
IANA maintains an informational listing on its web site concerning
Ethertypes, OUIs, and multicast addresses assigned under OUIs other
than the IANA OUI. The title of this informational registry is "IEEE
802 Numbers". IANA has merged in those Ethertypes listed in Appendix
B that were not already included. IANA will update that
informational registry when changes are provided by the Expert.
5.4. OUI Exhaustion
When the available space for either multicast or unicast EUI-48
identifiers under OUI 00-00-5E has been 90% or more exhausted, IANA
should request an additional OUI from the IEEE Registration Authority
for further IANA assignment. The appointed Expert(s) should monitor
for this condition and notify IANA.
5.5. IANA OUI MAC Address Table
No changes have been made in the "IANA Unicast 48-bit MAC Addresses"
and "IANA Multicast 48-bit MAC Addresses" tables except for the
updates to references as specified in the first part of Section 5.
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RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
5.6. SNAP Protocol Number Table and Assignment
The "SNAP PROTOCOL IDs" table has been renamed the "SNAP Protocol
Numbers" table. "PID" has been replaced by "Protocol Number".
IANA has assigned 0x0042 as the SNAP protocol number under the IANA
OUI to be used for documentation purposes.
6. Security Considerations
This document is concerned with assignment of parameters under the
IANA OUI and closely related matters. It is not directly concerned
with security except as follows.
Confusion and conflict can be caused by the use of MAC addresses or
other OUI-derived protocol parameters as examples in documentation.
Examples used "only" in documentation can end up being coded and
released or cause conflicts due to later real use and the possible
acquisition of intellectual property rights in such addresses or
parameters. The reservation herein of MAC addresses and parameters
for documentation purposes will minimize such confusion and conflict.
See [RFC7043] for security considerations in storing MAC addresses in
the DNS.
7. Acknowledgements
The comments and suggestions of the following people, listed in
alphabetic order, are gratefully acknowledged:
This document:
David Black, Adrian Farrel, Bob Grow, Joel Jaeggli, Pearl Liang,
Glenn Parsons, Pete Resnick, and Dan Romascanu.
RFC 5342:
Bernard Aboba, Scott O. Bradner, Ian Calder, Michelle Cotton, Lars
Eggert, Eric Gray, Alfred Hoenes, Russ Housley, Charlie Kaufman,
Erik Nordmark, Dan Romascanu, Geoff Thompson, and Mark Townsley.
Eastlake & Abley BCP [Page 20]
RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
8. References
8.1. Normative References
[802_O&A] "IEEE Standard for Local and Metropolitan Area Networks:
Overview and Architecture", IEEE Std 802-2001, 8 March
2002.
"IEEE Standard for Local and Metropolitan Area Networks:
Overview and Architecture / Amendment 1: Ethertypes for
Prototype and Vendor-Specific Protocol Development", IEEE
Std 802a-2003, 18 September 2003.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
8.2. Informative References
[802.1Q] "IEEE Standard for Local and metropolitan area networks /
Media Access Control (MAC) Bridges and Virtual Bridge
Local Area Networks", IEEE Std 802.1Q-2011, 31 August
2011.
[802.3] "IEEE Standard for Ethernet", IEEE Std 802.3-2012, 28
December 2012.
[802.11] "IEEE Standard for Information technology /
Telecommunications and information exchange between
systems / Local and metropolitan area networks / Specific
requirements / Part 11: Wireless LAN Medium Access Control
(MAC) and Physical Layer (PHY) Specifications", IEEE Std
802.11-2012, 29 March 2012.
[DOC-ADDR] Abley, J., "EUI-48 and EUI-64 Address Assignments for use
in Documentation", Work in Progress, March 2013.
[EUI-64] IEEE Registration Authority, "Guidelines for 64-bit Global
Identifier (EUI-64(TM))", <http://standards.ieee.org/
regauth/oui/tutorials/EUI64.html>, November 2012.
[IANA] Internet Assigned Numbers Authority,
<http://www.iana.org>.
[IEEE802] IEEE 802 LAN/MAN Standards Committee,
<http://www.ieee802.org>.
Eastlake & Abley BCP [Page 21]
RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
[InfiniBand]
InfiniBand Trade Association, "InfiniBand Architecture
Specification Volume 1", November 2007.
[RAC-OUI] Parsons, G., "OUI Registry Restructuring", Work in
Progress, September 2013.
[RFC1112] Deering, S., "Host extensions for IP multicasting", STD 5,
RFC 1112, August 1989.
[RFC1661] Simpson, W., Ed., "The Point-to-Point Protocol (PPP)", STD
51, RFC 1661, July 1994.
[RFC2153] Simpson, W., "PPP Vendor Extensions", RFC 2153, May 1997.
[RFC2332] Luciani, J., Katz, D., Piscitello, D., Cole, B., and N.
Doraswamy, "NBMA Next Hop Resolution Protocol (NHRP)", RFC
2332, April 1998.
[RFC2464] Crawford, M., "Transmission of IPv6 Packets over Ethernet
Networks", RFC 2464, December 1998.
[RFC2606] Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS
Names", BCP 32, RFC 2606, June 1999.
[RFC3092] Eastlake 3rd, D., Manros, C., and E. Raymond, "Etymology
of "Foo"", RFC 3092, April 1 2001.
[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, February 2006.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760, January
2007.
[RFC5214] Templin, F., Gleeson, T., and D. Thaler, "Intra-Site
Automatic Tunnel Addressing Protocol (ISATAP)", RFC 5214,
March 2008.
[RFC5332] Eckert, T., Rosen, E., Ed., Aggarwal, R., and Y. Rekhter,
"MPLS Multicast Encapsulations", RFC 5332, August 2008.
[RFC5342] Eastlake 3rd, D., "IANA Considerations and IETF Protocol
Usage for IEEE 802 Parameters", BCP 141, RFC 5342,
September 2008.
[RFC5737] Arkko, J., Cotton, M., and L. Vegoda, "IPv4 Address Blocks
Reserved for Documentation", RFC 5737, January 2010.
Eastlake & Abley BCP [Page 22]
RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
[RFC5798] Nadas, S., Ed., "Virtual Router Redundancy Protocol (VRRP)
Version 3 for IPv4 and IPv6", RFC 5798, March 2010.
[RFC6034] Thaler, D., "Unicast-Prefix-Based IPv4 Multicast
Addresses", RFC 6034, October 2010.
[RFC6895] Eastlake 3rd, D., "Domain Name System (DNS) IANA
Considerations", BCP 42, RFC 6895, April 2013.
[RFC7043] Abley, J., "Resource Records for EUI-48 and EUI-64
Addresses in the DNS", RFC 7043, October 2013.
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RFC 7042 IANA/IETF and IEEE 802 Parameters October 2013
Appendix A. Templates
This appendix provides the specific templates for IANA assignments of
parameters. Explanatory words in parentheses in the templates below
may be deleted in a completed template as submitted to IANA.
A.1. EUI-48/EUI-64 Identifier or Identifier Block Template
Applicant Name:
Applicant Email:
Applicant Telephone: (starting with country code)
Use Name: (brief name of Parameter use such as "Foo Protocol"
[RFC3092])
Document: (ID or RFC specifying use to which the identifier or block
of identifiers will be put.)
Specify whether this is an application for EUI-48 or EUI-64
identifiers:
Size of Block requested: (must be a power-of-two-sized block, can be
a block of size one (2**0))
Specify multicast, unicast, or both:
A.2. IANA OUI-Based Protocol Number Template
Applicant Name:
Applicant Email:
Applicant Telephone: (starting with country code)
Use Name: (brief name of use of code point such as "Foo Protocol")
Document: (ID or RFC specifying use to which the protocol identifier
will be put.)
Note: (any additional note)
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A.3. Other IANA OUI-Based Parameter Template
Applicant Name:
Applicant Email:
Applicant Telephone: (starting with country code)
Protocol where the OUI-Based Parameter for which a value is being
requested appears: (such as: Cipher Suite selection in IEEE 802.11)
Use Name: (brief name of use of code point to be assigned, such as
"Foo Cipher Suite" [RFC3092])
Document: (ID or RFC specifying use to which the other IANA OUI-based
parameter value will be put.)
Note: (any additional note)
Appendix B. Ethertypes
This appendix lists some Ethertypes specified for IETF protocols or
by IEEE 802 as known at the time of publication. A more up-to-date
list may be available on the IANA web site, currently at [IANA]. The
IEEE Registration Authority page of Ethertypes,
http://standards.ieee.org/regauth/ethertype/eth.txt, may also be
useful. See Section 3 above.
B.1. Some Ethertypes Specified by the IETF
0x0800 Internet Protocol Version 4 (IPv4)
0x0806 Address Resolution Protocol (ARP)
0x0808 Frame Relay ARP
0x22F3 TRILL
0x22F4 L2-IS-IS
0x8035 Reverse Address Resolution Protocol (RARP)
0x86DD Internet Protocol Version 6 (IPv6)
0x880B Point-to-Point Protocol (PPP)
0x880C General Switch Management Protocol (GSMP)
0x8847 MPLS
0x8848 MPLS with upstream-assigned label
0x8861 Multicast Channel Allocation Protocol (MCAP)
0x8863 PPP over Ethernet (PPPoE) Discovery Stage
0x8864 PPP over Ethernet (PPPoE) Session Stage
0x893B TRILL Fine Grained Labeling (FGL)
0x8946 TRILL RBridge Channel
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B.2. Some IEEE 802 Ethertypes
0x8100 IEEE Std 802.1Q - Customer VLAN Tag Type (C-Tag, formerly
called the Q-Tag) (initially Wellfleet)
0x8808 IEEE Std 802.3 - Ethernet Passive Optical Network (EPON)
0x888E IEEE Std 802.1X - Port-based network access control
0x88A8 IEEE Std 802.1Q - Service VLAN tag identifier (S-Tag)
0x88B5 IEEE Std 802 - Local Experimental Ethertype
0x88B6 IEEE Std 802 - Local Experimental Ethertype
0x88B7 IEEE Std 802 - OUI Extended Ethertype
0x88C7 IEEE Std 802.11 - Pre-Authentication (802.11i)
0x88CC IEEE Std 802.1AB - Link Layer Discovery Protocol (LLDP)
0x88E5 IEEE Std 802.1AE - Media Access Control Security
0x88F5 IEEE Std 802.1Q - Multiple VLAN Registration Protocol
(MVRP)
0x88F6 IEEE Std 802.1Q - Multiple Multicast Registration
Protocol (MMRP)
0x890D IEEE Std 802.11 - Fast Roaming Remote Request (802.11r)
0x8917 IEEE Std 802.21 - Media Independent Handover Protocol
0x8929 IEEE Std 802.1Qbe - Multiple I-SID Registration Protocol
0x8940 IEEE Std 802.1Qbg - ECP Protocol (also used in 802.1BR)
Appendix C. Documentation Protocol Number
Below is the template based on which an IANA OUI-based protocol
number value was assigned for document use. (See Section 3 and
Appendix A.2.)
Applicant Name: Donald E. Eastlake 3rd
Applicant Email: d3e3e3@gmail.com
Applicant Telephone: 1-508-333-2270
Use Name: Documentation
Document: This document.
Note: Request value 0x0042
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Authors' Addresses
Donald E. Eastlake 3rd
Huawei Technologies
155 Beaver Street
Milford, MA 01757
USA
Phone: +1-508-634-2066
EMail: d3e3e3@gmail.com
Joe Abley
Dyn, Inc.
470 Moore Street
London, ON N6C 2C2
Canada
Phone: +1 519 670 9327
EMail: jabley@dyn.com
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