IETF Last Call Review of draft-ietf-lsr-igp-flex-algo-reverse-affinity-06
review-ietf-lsr-igp-flex-algo-reverse-affinity-06-secdir-lc-hallam-baker-2025-06-04-00

 have reviewed this document as part of the security directorate's
ongoing effort to review all IETF documents being processed by the
IESG. These comments were written primarily for the benefit of the
security area directors. Document editors and WG chairs should treat
these comments just like any other last call comments.

The summary of the review is that the document is ready with the
exception of the TBD in the acknowledgements which isn't in security scope.

The document correctly incorporates by reference the security 
considerations of RFC9350 which in turn refer to existing drafts and
raise the point that the only security controls possible at this
layer are limited to authenticating the source of information, there
is no practical in-protocol mechanism for protecting against a 
node with authentication capability that is captured by an attacker 
beyond identifying rogue behavior and reacting accordingly.

[And this review is late because I spent rather too much time trying to
think up alternatives]