BGP EVPN Multihoming Extensions for Split-Horizon Filtering

Metadata

Publisher: IETF
Doc Type: Standard
Pages: 17
Abstract: An Ethernet Virtual Private Network (EVPN) is commonly used with Network Virtualization Overlay (NVO) tunnels as well as with MPLS and Segment Routing (SR) tunnels. The multihoming procedures in EVPN may vary based on the type of tunnel used within the EVPN Broadcast Domain. Specifically, there are two multihoming split-horizon procedures designed to prevent looped frames on multihomed Customer Edge (CE) devices: the Ethernet Segment Identifier (ESI) Label-based procedure and the local-bias procedure. The ESI Label-based split-horizon procedure is applied to MPLS-based tunnels such as MPLS over UDP (MPLSoUDP), while the local-bias procedure is used for other tunnels such as Virtual eXtensible Local Area Network (VXLAN) tunnels. Current specifications do not allow operators to choose which split-horizon procedure to use for tunnel encapsulations that support both methods. Examples of tunnels that may support both procedures include MPLSoUDP, MPLS over GRE (MPLSoGRE), Generic Network Virtualization Encapsulation (Geneve), and Segment Routing over IPv6 (SRv6) tunnels. This document updates the EVPN multihoming procedures described in RFCs 7432 and 8365, enabling operators to select the split-horizon procedure that meets their specific requirements.
Publication Date: 2025-03-01
Status Note: Proposed Standard
DOI: 10.17487/RFC9746
Link: https://doi.org/10.17487/RFC9746
Author(s): Jorge Rabadan
Kiran Nagaraj
Wen Lin
Ali Sajassi
Keyword(s): EVPN, Split Horizon Filtering, ESI, Encapsulation

Latest version of IETF RFC 9746

Document Versions — IETF RFC 9746

▶ IETF RFC 9746 (2025-03-01)

THIS DOC [ACTIVE] [LATEST VERSION]

Normative Reference(s)

IETF RFC 2119 [Active*]
IETF RFC 7432 [Active*]
IETF RFC 8126 [Active*]
IETF RFC 8174 [Active*]
RFC8365 — RFC8365 EXTERNAL
RFC9252 — RFC9252 EXTERNAL

Bibliographic Reference(s)

IETF.draft-ietf-bess-evpn-geneve-08 — I-D.ietf-bess-evpn-geneve EXTERNAL
IETF.draft-ietf-nvo3-vxlan-gpe-13 — I-D.ietf-nvo3-vxlan-gpe EXTERNAL
IANA, "Border Gateway Protocol (BGP) Tunnel Encapsulation", <https://www.iana.org/assignments/bgp-tunnel-encapsulation>. EXTERNAL
IETF RFC 4023 [Active*]
IETF RFC 7348 [Active*]
IETF RFC 7510 [Active*]
IETF RFC 7606 [Active*]
IETF RFC 7637 [Active*]
RFC8402 — RFC8402 EXTERNAL
RFC8660 — RFC8660 EXTERNAL
RFC8754 — RFC8754 EXTERNAL
RFC8926 — RFC8926 EXTERNAL
RFC8986 — RFC8986 EXTERNAL
IETF RFC 9012 [Active*]

Source Data (JSON)

Full registry record with provenance metadata. Open directly: /api/doc/RFC9746.json

Amends:

IETF RFC 7432 [Active*]

RFC8365 — RFC8365 EXTERNAL

Reference Tree

Explore all references and references to this document, as a navigable tree.

Open Reference Tree

Reference this Doc

Plain text (ISO 690 compliant)

Preview:

IETF RFC 9746, BGP EVPN Multihoming Extensions for Split-Horizon Filtering. Available at https://doi.org/10.17487/RFC9746

Snippet:

IETF RFC 9746, BGP EVPN Multihoming Extensions for Split-Horizon Filtering. Available at https://doi.org/10.17487/RFC9746

HTML (ISO 690 compliant)

Preview:

IETF RFC 9746, BGP EVPN Multihoming Extensions for Split-Horizon Filtering. Available at https://doi.org/10.17487/RFC9746

Snippet:

<span class="citation"><cite>IETF RFC 9746</cite>, BGP EVPN Multihoming Extensions for Split-Horizon Filtering. Available at <a href="https://doi.org/10.17487/RFC9746" target="_blank" rel="noopener">https://doi.org/10.17487/RFC9746</a></span>

SMPTE's HTML Pub

Preview:

IETF RFC 9746, BGP EVPN Multihoming Extensions for Split-Horizon Filtering
doi: 10.17487/RFC9746
url: https://doi.org/10.17487/RFC9746

Snippet:

<li>
<cite id="bib-rfc9746">IETF RFC 9746</cite>, BGP EVPN Multihoming Extensions for Split-Horizon Filtering
<span class="doi">10.17487/RFC9746</span>
</li>