ISO/IEC/IEEE 8802-1Q:2020

INTERNATIONAL ISO/IEC/
STANDARD IEEE
8802-1Q
Second edition
2020-08
Telecommunications and exchange
between information technology
systems — Requirements for local and
metropolitan area networks —
Part 1Q:
Bridges and bridged networks
Télécommunications et échange entre systèmes informatiques —
Exigences pour les réseaux locaux et métropolitains —
Partie 1Q: Ponts et réseaux pontés
Reference number
©
IEEE 2018
© IEEE 2018
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ii
Foreword
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ISO/IEC/IEEE 8802-1Q was prepared by the LAN/MAN of the IEEE Computer Society (as IEEE Std 802.1Q-
2018) 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 8802-1Q:2016), which has
been technically revised. It also incorporates the Amendments ISO/IEC/IEEE 8802-1Q:2016/
Amd.1:2017, ISO/IEC/IEEE 8802-1Q:2016/Amd.2:2018, ISO/IEC/IEEE 8802-1Q:2016/Amd.3:2017,
ISO/IEC/IEEE 8802-1Q:2016/Amd.4:2017, ISO/IEC/IEEE 8802-1Q:2016/Amd.5:2017, ISO/IEC/IEEE
8802-1Q:2016/Amd.6:2019, ISO/IEC/IEEE 8802-1Q:2016/Amd.7:2019 and the Corrigendum
ISO/IEC/IEEE 8802-1Q:2016/Cor.1:2017.
A list of all parts in the ISO/IEC/IEEE 8802 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
© IEEE 2018 - All rights reserved
iii
IEEE Std 802.1Q™-2018
(Revision of
IEEE Std 802.1Q-2014)
IEEE Standard for 
Local and Metropolitan Area Networks—
Bridges and Bridged Networks
Sponsor
LAN/MAN Standards Committee 
of the
IEEE Computer Society
Approved 7 May 2018
IEEE-SA Standards Board
Abstract: This standard specifies how the Media Access Control (MAC) Service is supported by
Bridged Networks, the principles of operation of those networks, and the operation of MAC Bridge s
and VLAN Bridges, including management, protocols, and algorithms. 
Keywords: Bridged Network, IEEE 802.1Q™, LAN, local area network, MAC Bridge, metropolitan
area network, MSTP, Multiple Spanning Tree Protocol, Rapid Spanning Tree Protocol, RSTP, PBN,
Provider Bridged Network, Shortest Path Bridging Protocol, SPB Protocol, Time-Sensitive
Networking, TSN, Virtual Bridged Network, virtual LAN, VLAN Bridge
The Institute of Electrical and Electronics Engineers, Inc.
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All rights reserved. Published 6 July 2018. Printed in the United States of America.
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Engineers, Incorporated.
PDF: ISBN 978-1-5044-4929-8 STD23139
Print: ISBN 978-1-5044-4930-4 STDPD23139
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