RFC 9117

Revised Validation Procedure for BGP Flow Specifications, August 2021

File formats:

icon for HTML icon for text file icon for v3pdf icon for XML
Also available: XML file for editing
RFC 8955
J. Uttaro
J. Alcaide
C. Filsfils
D. Smith
P. Mohapatra
idr (rtg)

Cite this RFC: TXT  |  XML  |   BibTeX

DOI:  https://doi.org/10.17487/RFC9117

Discuss this RFC: Send questions or comments to the mailing list idr@ietf.org

Other actions: Submit Errata  |  Find IPR Disclosures from the IETF  |  View History of RFC 9117


This document describes a modification to the validation procedure defined for the dissemination of BGP Flow Specifications. The dissemination of BGP Flow Specifications as specified in RFC 8955 requires that the originator of the Flow Specification match the originator of the best-match unicast route for the destination prefix embedded in the Flow Specification. For an Internal Border Gateway Protocol (iBGP) received route, the originator is typically a border router within the same autonomous system (AS). The objective is to allow only BGP speakers within the data forwarding path to originate BGP Flow Specifications. Sometimes it is desirable to originate the BGP Flow Specification from any place within the autonomous system itself, for example, from a centralized BGP route controller. However, the validation procedure described in RFC 8955 will fail in this scenario. The modification proposed herein relaxes the validation rule to enable Flow Specifications to be originated within the same autonomous system as the BGP speaker performing the validation. Additionally, this document revises the AS_PATH validation rules so Flow Specifications received from an External Border Gateway Protocol (eBGP) peer can be validated when such a peer is a BGP route server.

This document updates the validation procedure in RFC 8955.

For the definition of Status, see RFC 2026.

For the definition of Stream, see RFC 8729.

Advanced Search