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. I have read version -02 as TSV-ART reviewer. The document is short and well-written. The described solution for encoding TCP header flags in IPFIX seems to make sense given the recent updates of the TCP standard, and future changes in future. However, please note that I am not an IPFIX expert.