ISO/IEC/IEEE 8802-1AX:2021

Telecommunications and exchange between information technology systems — Requirements for local and metropolitan area networks — Part 1AX: Link aggregation

Télécommunications et échange entre systèmes informatiques — Exigences pour les réseaux locaux et métropolitains — Partie 1AX: Agrégation de lien

General Information

• Status: Published
• Publication Date: 12-Sep-2021
• ICS: 35.110 - Networking
• Technical Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Drafting Committee: ISO/IEC JTC 1/SC 6 - Telecommunications and information exchange between systems
• Current Stage: 6060 - International Standard published
• Start Date: 13-Sep-2021
• Due Date: 28-Aug-2022
• Completion Date: 13-Sep-2021

Relations

• Revises: ISO/IEC/IEEE 8802-1AX:2016 - Information technology — Telecommunications and information exchange between systems — Local and metropolitan area networks — Specific requirements — Part 1AX: Link aggregation
• Effective Date: 18-Apr-2021

Standards Content (Sample)

INTERNATIONAL ISO/IEC/
STANDARD IEEE
8802-1AX
Second edition
2021-09
Telecommunications and exchange
between information technology
systems — Requirements for local and
metropolitan area networks —
Part 1AX:
Link aggregation
Télécommunications et échange entre systèmes informatiques —
Exigences pour les réseaux locaux et métropolitains —
Partie 1AX: Agrégation de lien
Reference number
ISO/IEC/IEEE 8802-1AX:2021(E)
©
IEEE 2020

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ISO/IEC/IEEE 8802-1AX:2021(E)

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Email: [e-mail]
Website: www.ieee.org
Published in Switzerland
ii © IEEE 2020 – All rights reserved

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ISO/IEC/IEEE FDIS 8802-1AX:2021(E)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
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The procedures used to develop this document and those intended for its further maintenance are
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different types of ISO/IEC documents should be noted.
IEEE Standards documents are developed within the IEEE Societies and the Standards Coordinating
Committees of the IEEE Standards Association (IEEE-SA) Standards Board. The IEEE develops its
standards through a consensus development process, approved by the American National Standards
Institute, which brings together volunteers representing varied viewpoints and interests to achieve the
final product. Volunteers are not necessarily members of the Institute and serve without compensation.
While the IEEE administers the process and establishes rules to promote fairness in the consensus
development process, the IEEE does not independently evaluate, test, or verify the accuracy of any of the
information contained in its standards.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights. Details
of any patent rights identified during the development of the document will be in the Introduction and/or
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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
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 www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
ISO/IEC/IEEE 8802-1AX was prepared by the LAN/MAN of the IEEE Computer Society (as IEEE Std
802.1AX-2020) and drafted in accordance with its editorial rules. It was adopted, under the “fast-track
procedure” defined in the Partner Standards Development Organization cooperation agreement between
ISO and IEEE, by Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 6,
Telecommunications and information exchange between systems.
This second edition cancels and replaces the first edition (ISO/IEC/IEEE 8802-1AX:2016), which has
been technically revised. It also incorporates the Technical Corrigendum ISO/IEC/IEEE 8802-
1AX:2016/Cor 1:2018.
A list of all parts in the ISO/IEC/IEEE 8802 series can be found on the ISO and IEC websites.
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committees.
© IEEE 2020 – All rights reserved iii

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IEEE Std 802.1AX™-2020
(Revision of IEEE Std 802.1AX-2014)
IEEE Standard for
Local and Metropolitan Area Networks—
Link Aggregation
Developed by the
LAN/MAN Standards Committee
of the
IEEE Computer Society
Approved 30 January 2020
IEEE SA Standards Board

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ISO/IEC/IEEE 8802-1AX:2021(E)
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ISO/IEC/IEEE 8802-1AX:2021(E)
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ISO/IEC/IEEE 8802-1AX:2021(E)
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ISO/IEC/IEEE 8802-1AX:2021(E)
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ISO/IEC/IEEE 8802-1AX:2021(E)
Participants
At the time this revision was submitted to the IEEE SA for approval, the IEEE P802.1 Working Group had
the following membership:
Glenn Parsons, Chair
John Messenger, Vice Chair
János Farkas, Chair, Time-Sensitive Networking Task Group
Stephen Haddock and Jessy Rouyer, Co-Editors
Astrit Ademaj Yoshihiro Ito
Maximilian Riegel
Ralf Assmann Michael Karl Atsushi Sato
Jens Bierschenk Stephan Kehrer Frank Schewe
Christian Boiger Randy Kelsey Michael Seaman
Paul Bottorff Hajime Koto Maik Seewald
James Lawlis
Radhakrishna Canchi Johannes Specht
Feng Chen Christophe Mangin Marius Stanica
Weiying Cheng Scott Mansfield Guenter Steindl
Paul Congdon Kenichi Maruhashi Karim Traore
Rodney Cummings David McCall
Hao Wang
Josef Dorr Larry McMillan Tongtong Wang
Hesham Elbakoury Tero Mustala Xinyuan Wang
Thomas Enzinger Roy Myers Karl Weber
Donald Fedyk Hiroki Nakano Brian Weis
Bob Noseworthy
Norman Finn Ludwig Winkel
Geoffrey Garner Tomoki Ohsawa Jordon Woods
Craig Gunther Hiroshi Ohue Takahiro Yamaura
Marina Gutierrez Donald R. Pannell Nader Zein
Mark Hantel Michael Potts
William Zhao
Marc Holness Dieter Proell Helge Zinner
Satoko Itaya Wei Qiu Harald Zweck
Karen Randall
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ISO/IEC/IEEE 8802-1AX:2021(E)
The following members of the balloting committee voted on this standard. Balloters may have voted for
approval, disapproval, or abstention.
Raj Jain Bansi Patel
Thomas Alexander
Sangkwon Jeong
Richard Alfvin Brian Petry
Butch Anton Pranav Jha David Piehler
Lokesh Kabra Walter Pienciak
Stefan Aust
Srinivas Kandala
Harry Bims Rick Pimpinella
Kenneth Bow Piotr Karocki Clinton Powell
Stuart Kerry R. K. Rannow
Rich Boyer
Evgeny Khorov
Nancy Bravin Maximilian Riegel
Vern Brethour Yongbum Kim Robert Robinson
Robert Landman
Demetrio Bucaneg Jessy Rouyer
Hyeong Ho Lee
William Byrd John Sargent
Radhakrishna Canchi John Lemon Frank Schewe
James Lepp
Paul Cardinal Michael Seaman
Michael Lynch
Juan Carreon Thomas Starai
Pin Chang John Mackay Walter Struppler
Roger Marks
János Farkas Michael Thompson
Arthur Marris
John Fletcher Mark-Rene Uchida
Avraham Freedman Jeffery Masters James Van De Ligt
Brett Mcclellan
Devon Gayle Dmitri Varsanofiev
Zhigang Gong Richard Mellitz George Vlantis
Randall Groves Jose Morales Stephen Webb
Ronald Murias
Stephen Haddock Karl Weber
Marek Hajduczenia Bruce Muschlitz Hung-Yu Wei
Marco Hernandez Nick S. A. Nikjoo Scott Willy
Satoshi Obara
Werner Hoelzl Peter Wu
Yasuhiro Hyakutake Carlos Pardo Oren Yuen
Satoko Itaya Nader Zein
When the IEEE-SA Standards Board approved this standard on 30 January 2020, it had the following
membership:
Gary Hoffman, Chair
Vacant Position, Vice Chair
Jean-Philippe Faure, Past Chair
Konstantinos Karachalios, Secretary
Ted Burse Howard Li Dorothy Stanley
J. Travis Griffith Dong Liu Mehmet Ulema
Grace Gu Kevin Lu Lei Wang
Guido R. Hiertz Paul Nikolich
Sha Wei
Joseph L. Koepfinger* Damir Novosel Philip B. Winston
John D. Kulick Jon Walter Rosdahl Daidi Zhong
David J. Law Jingyi Zhou
*Member Emeritus
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ISO/IEC/IEEE 8802-1AX:2021(E)
Introduction
(This introduction is not part of IEEE Std 802.1AX-2020, IEEE Standard for Local and Metropolitan Area
Networks—Link Aggregation.)
Link Aggregation allows one or more links to be aggregated together to form a Link Aggregation Group
(LAG) so that the Link Aggregation Client can treat the LAG as if it were a single link. Link Aggregation
was originally published as IEEE Std 802.3ad™-2000 and subsequently incorporated into the
IEEE Std 802.3™, 2000 Edition. In 2008 Link Aggregation was removed from IEEE Std 802.3 and
published as IEEE Std 802.1AX-2008. These standards specified the aggregation of full-duplex point-to-
point links using IEEE Std 802.3 media of the same speed.
An amendment, IEEE Std 802.1AXbk™-2012, specified changes to the addressing used by the link
aggregation control and marker protocols to allow a LAG to span Two-Port Media Access Control (MAC)
Relays (TPMRs) and to span Provider Bridged Networks and Provider Backbone Bridge Networks.
A revision, IEEE Std 802.1AX-2014, extended Link Aggregation in three areas. First, it explicitly allowed
the aggregation of point-to-point links of any speed using any physical media or logical connection capable
of supporting the Internal Sublayer Service specified in IEEE Std 802.1AC™. Second, it specified
Conversation-Sensitive Collection and Distribution (CSCD) that provides a mechanism to identify the
distribution algorithm in use to map data frames to individual links in the LAG and to convey that
information to the Link Aggregation Partner via Link Aggregation Control Protocol Data Units (LACPDUs)
containing version 2 type/length/values (TLVs). Third, it specified Distributed Resilient Network
Interconnect (DRNI) that allows a LAG to terminate at two or three cooperating Systems so that the LAG
provides resiliency to System-level failures as well as link level failures. A corrigendum, IEEE Std
802.1AX-2014/Cor 1-2017, provided technical and editorial corrections to CSCD.
This revision, IEEE Std 802.1AX-2020, makes significant refinements and simplifications to the Link
Aggregation Control Protocol (LACP) as well as to CSCD and DRNI. In LACP, the Periodic state machine
and Transmit state machine are combined to a single machine, and the Mux machine is optimized to reduce
the likelihood of excessive Link Aggregation Control Protocol Data Unit (LACPDU) transmissions. CSCD
is refined to eliminate the TLVs that led to LACPDUs greater than 128 bytes in length. DRNI is significantly
revised and simplified to support a LAG terminating at just two (not three) cooperating Systems.
Every effort has been made to maintain interoperability, without prior configuration, with LACP
implementations conforming to IEEE Std 802.3ad-2000, IEEE Std 802.1AX-2008, or IEEE Std 802.1AX-
2014 and with CSCD implementations conforming to IEEE Std 802.1AX-2014. The changes to DRNI, and
in particular the Distributed Relay Control Protocol (DRCP), are such that an implementation conforming to
this standard will not interoperate with a DRCP implementation conforming to IEEE Std 802.1AX-2014.
The DRCP version number in this standard has been changed to version 2, and care has been taken so that a
DRCP implementation conformant to IEEE Std 802.1AX-2014 will discard version 2 DRCPDUs as invalid
and that implementations of this standard will discard version 1 DRCPDUs.
This standard contains state-of-the-art material. The area covered by this standard is undergoing evolution.
Revisions are anticipated within the next few years to clarify existing material, to correct possible errors, and
to incorporate new related material. Information on the current revision state of this and other IEEE 802
standards may be obtained from
Secretary, IEEE-SA Standards Board
445 Hoes Lane
Piscataway, NJ 08854
USA
8
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ISO/IEC/IEEE 8802-1AX:2021(E)
Contents
1. Overview. 18
1.1 Scope. 18
1.2 Purpose. 18
1.3 State diagram conventions . 19
2. Normative references. 20
3. Definitions . 21
4. Acronyms and abbreviations . 24
5. Conformance. 25
5.1 Requirements terminology. 25
5.2 Protocol implementation conformance statement. 25
5.3 Link Aggregation. 25
5.3.2 Link Aggregation options . 26
5.4 Distributed Resilient Network Interconnect (DRNI). 26
5.4.2 DRNI options. 27
6. Link Aggregation. 28
6.1 Overview. 28
6.1.1 Goals and objectives . 28
6.1.2 Positioning of Link Aggregation within the IEEE 802 architecture. 29
6.1.3 Protocol Parser/Multiplexer. 29
6.1.3.1 Protocol Parser state diagram . 30
6.2 Link Aggregation operation. 31
6.2.1 Principles of Link Aggregation. 33
6.2.2 Service interfaces. 34
6.2.3 Frame Collector . 34
6.2.3.1 Frame Collector state diagram. 35
6.2.4 Frame Distributor. 36
6.2.4.1 Frame Distributor state diagram . 36
6.2.5 Marker Generator/Receiver (optional). 37
6.2.6 Marker Responder. 38
6.2.7 Aggregator Parser/Multiplexer . 38
6.2.7.1 Aggregator Parser/Multiplexer state diagrams . 38
6.2.8 Aggregator . 42
6.2.9 LACP Parser/Multiplexer . 43
6.2.10 Addressing . 43
6.2.10.1 Source address (SA). 43
6.2.10.2 Destination address (DA). 43
6.3 Link Aggregation Control.
...

FINAL
INTERNATIONAL ISO/IEC/
DRAFT
STANDARD IEEE/FDIS
8802-1AX
ISO/IEC JTC 1/SC 6
Telecommunications and exchange
Secretariat: KATS
between information technology
Voting begins on:
2021-03-11 systems — Requirements for local
and metropolitan area networks —
Voting terminates on:
2021-07-29
Part 1AX:
Link aggregation
Télécommunications et échange entre systèmes informatiques
— Exigences pour les réseaux locaux et métropolitains —
Partie 1AX: Agrégation de lien
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/IEC/IEEE FDIS 8802-1AX:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. IEEE 2020

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ISO/IEC/IEEE FDIS 8802-1AX:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© IEEE 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from IEEE at the address below.
Institute of Electrical and Electronics Engineers, Inc
3 Park Avenue, New York
NY 10016-5997, USA
Email: [e-mail]
Website: www.ieee.org
Published in Switzerland
ii © IEEE 2020 – All rights reserved

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ISO/IEC/IEEE FDIS 8802-1AX:2021(E)
Foreword
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Commission) form the specialized system for worldwide standardization. National bodies that are
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The procedures used to develop this document and those intended for its further maintenance are
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different types of ISO/IEC documents should be noted.
IEEE Standards documents are developed within the IEEE Societies and the Standards Coordinating
Committees of the IEEE Standards Association (IEEE-SA) Standards Board. The IEEE develops its
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ISO/IEC/IEEE 8802-1AX was prepared by the LAN/MAN of the IEEE Computer Society (as IEEE Std
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© IEEE 2020 – All rights reserved iii

---------------------- Page: 3 ----------------------
IEEE Std 802.1AX™-2020
(Revision of IEEE Std 802.1AX-2014)
IEEE Standard for
Local and Metropolitan Area Networks—
Link Aggregation
Developed by the
LAN/MAN Standards Committee
of the
IEEE Computer Society
Approved 30 January 2020
IEEE SA Standards Board

---------------------- Page: 4 ----------------------
ISO/IEC/IEEE 8802-1AX:2021(E)
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ISO/IEC/IEEE 8802-1AX:2021(E)
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ISO/IEC/IEEE 8802-1AX:2021(E)
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ISO/IEC/IEEE 8802-1AX:2021(E)
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Copyright © 2020 IEEE. All rights reserved.

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ISO/IEC/IEEE 8802-1AX:2021(E)
Participants
At the time this revision was submitted to the IEEE SA for approval, the IEEE P802.1 Working Group had
the following membership:
Glenn Parsons, Chair
John Messenger, Vice Chair
János Farkas, Chair, Time-Sensitive Networking Task Group
Stephen Haddock and Jessy Rouyer, Co-Editors
Astrit Ademaj Yoshihiro Ito
Maximilian Riegel
Ralf Assmann Michael Karl Atsushi Sato
Jens Bierschenk Stephan Kehrer Frank Schewe
Christian Boiger Randy Kelsey Michael Seaman
Paul Bottorff Hajime Koto Maik Seewald
James Lawlis
Radhakrishna Canchi Johannes Specht
Feng Chen Christophe Mangin Marius Stanica
Weiying Cheng Scott Mansfield Guenter Steindl
Paul Congdon Kenichi Maruhashi Karim Traore
Rodney Cummings David McCall
Hao Wang
Josef Dorr Larry McMillan Tongtong Wang
Hesham Elbakoury Tero Mustala Xinyuan Wang
Thomas Enzinger Roy Myers Karl Weber
Donald Fedyk Hiroki Nakano Brian Weis
Bob Noseworthy
Norman Finn Ludwig Winkel
Geoffrey Garner Tomoki Ohsawa Jordon Woods
Craig Gunther Hiroshi Ohue Takahiro Yamaura
Marina Gutierrez Donald R. Pannell Nader Zein
Mark Hantel Michael Potts
William Zhao
Marc Holness Dieter Proell Helge Zinner
Satoko Itaya Wei Qiu Harald Zweck
Karen Randall
6
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ISO/IEC/IEEE 8802-1AX:2021(E)
The following members of the balloting committee voted on this standard. Balloters may have voted for
approval, disapproval, or abstention.
Raj Jain Bansi Patel
Thomas Alexander
Sangkwon Jeong
Richard Alfvin Brian Petry
Butch Anton Pranav Jha David Piehler
Lokesh Kabra Walter Pienciak
Stefan Aust
Srinivas Kandala
Harry Bims Rick Pimpinella
Kenneth Bow Piotr Karocki Clinton Powell
Stuart Kerry R. K. Rannow
Rich Boyer
Evgeny Khorov
Nancy Bravin Maximilian Riegel
Vern Brethour Yongbum Kim Robert Robinson
Robert Landman
Demetrio Bucaneg Jessy Rouyer
Hyeong Ho Lee
William Byrd John Sargent
Radhakrishna Canchi John Lemon Frank Schewe
James Lepp
Paul Cardinal Michael Seaman
Michael Lynch
Juan Carreon Thomas Starai
Pin Chang John Mackay Walter Struppler
Roger Marks
János Farkas Michael Thompson
Arthur Marris
John Fletcher Mark-Rene Uchida
Avraham Freedman Jeffery Masters James Van De Ligt
Brett Mcclellan
Devon Gayle Dmitri Varsanofiev
Zhigang Gong Richard Mellitz George Vlantis
Randall Groves Jose Morales Stephen Webb
Ronald Murias
Stephen Haddock Karl Weber
Marek Hajduczenia Bruce Muschlitz Hung-Yu Wei
Marco Hernandez Nick S. A. Nikjoo Scott Willy
Satoshi Obara
Werner Hoelzl Peter Wu
Yasuhiro Hyakutake Carlos Pardo Oren Yuen
Satoko Itaya Nader Zein
When the IEEE-SA Standards Board approved this standard on 30 January 2020, it had the following
membership:
Gary Hoffman, Chair
Vacant Position, Vice Chair
Jean-Philippe Faure, Past Chair
Konstantinos Karachalios, Secretary
Ted Burse Howard Li Dorothy Stanley
J. Travis Griffith Dong Liu Mehmet Ulema
Grace Gu Kevin Lu Lei Wang
Guido R. Hiertz Paul Nikolich
Sha Wei
Joseph L. Koepfinger* Damir Novosel Philip B. Winston
John D. Kulick Jon Walter Rosdahl Daidi Zhong
David J. Law Jingyi Zhou
*Member Emeritus
7
Copyright © 2020 IEEE. All rights reserved.

---------------------- Page: 10 ----------------------
ISO/IEC/IEEE 8802-1AX:2021(E)
Introduction
(This introduction is not part of IEEE Std 802.1AX-2020, IEEE Standard for Local and Metropolitan Area
Networks—Link Aggregation.)
Link Aggregation allows one or more links to be aggregated together to form a Link Aggregation Group
(LAG) so that the Link Aggregation Client can treat the LAG as if it were a single link. Link Aggregation
was originally published as IEEE Std 802.3ad™-2000 and subsequently incorporated into the
IEEE Std 802.3™, 2000 Edition. In 2008 Link Aggregation was removed from IEEE Std 802.3 and
published as IEEE Std 802.1AX-2008. These standards specified the aggregation of full-duplex point-to-
point links using IEEE Std 802.3 media of the same speed.
An amendment, IEEE Std 802.1AXbk™-2012, specified changes to the addressing used by the link
aggregation control and marker protocols to allow a LAG to span Two-Port Media Access Control (MAC)
Relays (TPMRs) and to span Provider Bridged Networks and Provider Backbone Bridge Networks.
A revision, IEEE Std 802.1AX-2014, extended Link Aggregation in three areas. First, it explicitly allowed
the aggregation of point-to-point links of any speed using any physical media or logical connection capable
of supporting the Internal Sublayer Service specified in IEEE Std 802.1AC™. Second, it specified
Conversation-Sensitive Collection and Distribution (CSCD) that provides a mechanism to identify the
distribution algorithm in use to map data frames to individual links in the LAG and to convey that
information to the Link Aggregation Partner via Link Aggregation Control Protocol Data Units (LACPDUs)
containing version 2 type/length/values (TLVs). Third, it specified Distributed Resilient Network
Interconnect (DRNI) that allows a LAG to terminate at two or three cooperating Systems so that the LAG
provides resiliency to System-level failures as well as link level failures. A corrigendum, IEEE Std
802.1AX-2014/Cor 1-2017, provided technical and editorial corrections to CSCD.
This revision, IEEE Std 802.1AX-2020, makes significant refinements and simplifications to the Link
Aggregation Control Protocol (LACP) as well as to CSCD and DRNI. In LACP, the Periodic state machine
and Transmit state machine are combined to a single machine, and the Mux machine is optimized to reduce
the likelihood of excessive Link Aggregation Control Protocol Data Unit (LACPDU) transmissions. CSCD
is refined to eliminate the TLVs that led to LACPDUs greater than 128 bytes in length. DRNI is significantly
revised and simplified to support a LAG terminating at just two (not three) cooperating Systems.
Every effort has been made to maintain interoperability, without prior configuration, with LACP
implementations conforming to IEEE Std 802.3ad-2000, IEEE Std 802.1AX-2008, or IEEE Std 802.1AX-
2014 and with CSCD implementations conforming to IEEE Std 802.1AX-2014. The changes to DRNI, and
in particular the Distributed Relay Control Protocol (DRCP), are such that an implementation conforming to
this standard will not interoperate with a DRCP implementation conforming to IEEE Std 802.1AX-2014.
The DRCP version number in this standard has been changed to version 2, and care has been taken so that a
DRCP implementation conformant to IEEE Std 802.1AX-2014 will discard version 2 DRCPDUs as invalid
and that implementations of this standard will discard version 1 DRCPDUs.
This standard contains state-of-the-art material. The area covered by this standard is undergoing evolution.
Revisions are anticipated within the next few years to clarify existing material, to correct possible errors, and
to incorporate new related material. Information on the current revision state of this and other IEEE 802
standards may be obtained from
Secretary, IEEE-SA Standards Board
445 Hoes Lane
Piscataway, NJ 08854
USA
8
Copyright © 2020 IEEE. All rights reserved.

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ISO/IEC/IEEE 8802-1AX:2021(E)
Contents
1. Overview. 18
1.1 Scope. 18
1.2 Purpose. 18
1.3 State diagram conventions . 19
2. Normative references. 20
3. Definitions . 21
4. Acronyms and abbreviations . 24
5. Conformance. 25
5.1 Requirements terminology. 25
5.2 Protocol implementation conformance statement. 25
5.3 Link Aggregation. 25
5.3.2 Link Aggregation options . 26
5.4 Distributed Resilient Network Interconnect (DRNI). 26
5.4.2 DRNI options. 27
6. Link Aggregation. 28
6.1 Overview. 28
6.1.1 Goals and objectives . 28
6.1.2 Positioning of Link Aggregation within the IEEE 802 architecture. 29
6.1.3 Protocol Parser/Multiplexer. 29
6.1.3.1 Protocol Parser state diagram . 30
6.2 Link Aggregation operation. 31
6.2.1 Principles of Link Aggregation. 33
6.2.2 Service interfaces. 34
6.2.3 Frame Collector . 34
6.2.3.1 Frame Collector state diagram. 35
6.2.4 Frame Distributor. 36
6.2.4.1 Frame Distributor state diagram . 36
6.2.5 Marker Generator/Receiver (optional). 37
6.2.6 Marker Responder. 38
6.2.7 Aggregator Parser/Multiplexer . 38
6.2.7.1 Aggregator Parser/Multiplexer state diagrams . 38
6.2.8 Aggregator . 42
6.2
...