This document has been reviewed as part of the transport area review team's ongoing effort to review key IETF documents. These comments were written primarily for the transport area directors, but are copied to the document's authors and WG to allow them to address any issues raised and also to the IETF discussion list for information. When done at the time of IETF Last Call, the authors should consider this review as part of the last-call comments they receive. Please always CC tsv-art@ietf.org if you reply to or forward this review. As far as I can see there are no fundamental transport-related issues in this document. All in all, the impact of selecting a Group Designated Router may be quite similar to the existing PIM-SM selection of a Designated Router. A little bit of wordsmithing: In Section 6, it could be useful to replace the term "enough total capacity" by another term, such as "enough available capacity" or "enough spare capacity". The router links can obviously also carry other, non-PIM traffic. Then there must be enough available bandwidth left for the PIM traffic on top of non-PIM traffic. The term "total capacity" is a bit vague; it could possibly refer to the physical link capacity (e.g., 1 Gbit/s for Gigabit Ethernet). Only considering the physical link capacity would not be correct. Actually, one could write more about the traffic engineering aspects of GDR selection, e.g., whether it is realistic that traffic distribution is really equal. Yet, given that there seems to be only one implementation according to the shepherd write-up, just changing the term may be sufficient.