Last Call Review of draft-ietf-pim-drlb-13
review-ietf-pim-drlb-13-secdir-lc-wallace-2019-11-14-00

I 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.

This document defines an extension to the PIM-SM protocol to allow some
responsibilities of is Designated Router to be distributed amongst a set of
routers instead of the router elected as DR.

The document is well written and has clear examples. The security
considerations references those of the DR as applicable to the new mechanism.
This seems fine.  One minor comment, the last sentence in the operational
considerations section seemed odd to me. It wasn't clear to me why migration
between different hash algorithms is not considered in this document (or why
this is much different from changes in DR priority, which is also required to
be considered as a GDR candidate).

The document is ready to my eye.