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. Thanks to the authors for this clear and useful document. Reducing the overhead of redundant multicast packets is a good improvement! The main transport-related comment I have is for section 3.3.1: “ Routers MAY support a configurable option for sending PackedAssert messages twice in short order (such as 50msec apart), to overcome possible loss, but only when the following two conditions are met.” How will an end point decide to retransmit like that or not? How is loss detected? I did find several nits: “RP” is mentioned in the introduction before it is defined. It would be useful to expand this here. It would also be good to expand “AT” on first use. Section 3.2 seems to have a formatting issue, with “ If the P)acked flag is 0”. Do you mean “ If the (P) flag is 0”? This section also says “If the (P) flag is 2”; how can a 1-bit flag have a value of 2? In section 3.3, “Only the compactness of their encoding” is a sentence fragment, not a complete sentence. In section 3.3.1, this normative requirement is confusingly worded: “ Implementation SHOULD NOT send only Asserts, but no PackedAsserts under all conditions, when all routers on the LAN do support Assert Packing.” Can you rephrase? In the same section, please add a reference when discussing DSCP markings. In section 4: In the packed form, are the version/flags fields repeated? Do we need to mandate normatively that the packed flags are not nested? It’s implied but not normatively said. In section 4.4.1, the field description order doesn’t seem to match the structure values in the diagram.