CurrentPROPOSED STANDARDIETF stream

RFC 9234: Route Leak Prevention and Detection Using Roles in UPDATE and OPEN Messages

In plain English — editorial summary, not part of the RFC

Route leaks are the propagation of BGP prefixes that violate assumptions of BGP topology relationships, e.g., announcing a route learned from one transit provider to another transit provider or a lateral (i.e., non-transit) peer or announcing a route learned from one lateral peer to another lateral peer or a transit provider. These are usually the result of misconfigured or absent BGP route filtering or lack of coordination between autonomous systems (ASes). Existing approaches to leak prevention rely on marking routes by operator configuration, with no check that the configuration corresponds to that of the External BGP (eBGP) neighbor, or enforcement of the two eBGP speakers agreeing on the peering relationship. This document enhances the BGP OPEN message to establish an agreement of the peering relationship on each eBGP session between autonomous systems in order to enforce appropriate configuration on both sides. Propagated routes are then marked according to the agreed relationship, allowing both prevention and detection of route leaks.

Document record

Document ID: RFC9234
Published: May 2022
Authors: A. Azimov; E. Bogomazov; R. Bush; K. Patel; K. Sriram
Status: PROPOSED STANDARD
Stream: IETF
Area: rtg
Pages: 12
Also known as: —

Topics

Also filed under

About this page

The document record above — title, authors, date, status, stream, area, relationships, DOI and errata — is imported verbatim from the public RFC Editor index. The “in plain English” section is editorial: written by The metasystema editorial team, not part of the RFC. Where the two differ, the RFC text governs.

Last checked against the RFC Editor index on 23 August 2026. RFCs are never revised after publication; changes are issued as new documents.

Data sources · Editorial policy · Report a correction · What is an RFC?