Segment Routing Path MTU in BGP

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Document Type Expired Internet-Draft (individual)
Last updated 2019-06-30 (latest revision 2018-12-27)
Replaced by draft-ietf-idr-sr-policy-path-mtu
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


Segment routing is a source routing paradigm that explicitly indicates the forwarding path for packets at the ingress node. An SR policy is a set of candidate SR paths consisting of one or more segment lists with necessary path attributes. However, the path maximum transmission unit (MTU) information for SR path is not available in the SR policy since the SR does not require signaling. This document defines extensions to BGP to distribute path MTU information within SR policies.


Cheng Li (
Zhenbin Li (

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