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. Overall, the document has no direct transport issues. There are potential issues in coupled documents, notably in draft-ietf-idr-rfc5575bis. Section 4.2.2.4 of that other document indicates three issues of concern: 1) inability to handle transport protocols other than TCP and UDP (e.g., SCTP or DCCP), 2) inability to handle any but initial fragments, and 3) the omission of addressing MTU issues in the associated tunnels. Presumably those will be addressed when that document is reviewed more thoroughly. Nits: I would encourage a revision of the abstract to focus on this document and its contributions, particularly as a single paragraph. The abstract of this document buries the lede; the final sentence would be usefully moved to the front and supporting material explaining context can be moved into the intro or a background section. The abstract could more usefully provide a summary of the actual contents of this document instead, e.g., from paragraph 7 of the introduction. The introduction has similar issues; the document itself is not discussed until the 6th paragraph. Again, it would be useful to focus on this document and address the relation of its contents to other documents and the overall PCE architecture in a background section separately. It also seems odd that this paragraph (#6 of the intro) undermines the terminology of the document that this supplements (as cited in the abstract). These documents as a pair should have consistent use of terminology, coining new terms as needed rather than redefining a key term as different in the two.