Abstract
Systems and methods are disclosed for signaling Attachment Circuit (AC) state in an Ethernet Virtual Private Network (EVPN) without withdrawing Ethernet Auto-Discovery per EVPN Instance (ETH-AD per EVI) routes. A local Provider Edge (PE) router sets an AC Down Bit within the Layer 2 Attributes Extended Community of an ETH-AD per EVI route to indicate that an associated AC has transitioned to a non-operational state, while retaining the existing route advertisement and the associated label programming in the control plane and the data plane. A multi-homed PE that receives the route excludes the advertising local PE from Designated Forwarder (DF) election for the affected EVPN Instance. A remote PE performs a switchover to a backup path or removes the affected path from an Equal Cost Multi-Path set without deprogramming labels, which reduces control plane and data plane churn in scaled EVPN deployments.
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Anonymous, "Improvement of AC State Handling in EVPN", Technical Disclosure Commons, (May 18, 2026)
https://www.tdcommons.org/dpubs_series/10147