Last Call Review of draft-ietf-savnet-intra-domain-problem-statement-09
review-ietf-savnet-intra-domain-problem-statement-09-rtgdir-lc-dunbar-2025-01-15-00

General Comments:
The document could benefit from more concise wording. Some sections are overly
verbose and could be streamlined without losing critical information.

The document effectively describes two existing methods for Source Address
Validation (SAV): Access Control Lists (ACLs) and Unicast Reverse Path
Forwarding (uRPF). It highlights that ACLs have a high operational cost due to
the need for manual updates and maintenance in dynamic networks. uRPF, while
automated, struggles with asymmetric routing scenarios, leading to improper
blocking of legitimate traffic. These limitations are well known, and the
document does not provide sufficient new insights into overcoming them.

Section 5 (Requirements for New SAV Mechanisms):

The requirements listed in this section reflect desirable outcomes for any SAV
mechanism, such as automatic updates, accurate validation, and support for
incremental deployment. The previous efforts likely shared similar goals but
may have been deemed too complex or expensive to implement at scale. A more
valuable approach would be to discuss the technical challenges or trade-offs
involved in meeting these requirements and propose specific  frameworks to
address them.

The document would benefit from an exploration of why these challenges remain
unresolved and how new methods could overcome them.

Best Regards,
Linda Dunbar