This review is performed as part of the INTAREA cross-area review. There do not appear to be any INTAREA issues in this document. NOTE: as author of the UDP options on which this document is based, I have some other concerns noted below, which are the "issues" indicated in the review result (ready with issues). There are some misconceptions about UDP options that should be corrected in this document: Regarding SAFE options: - “Such options can be silently ignored by receivers without affecting the meaning of the UDP user data” - Should be “Such options can be silently ignored by legacy receivers because they do not alter the UDP user data” Regarding UNSAFE options: - “Such options are not safe to ignore” - Should be “Such options are not safe tor legacy receivers to ignore because they alter the UDP user data” The document should be more clear that UDP options occur per-packet within a flow and can be introduced at any time in the flow (unlike TCP). Sec 4.1 needs to indicate use of a field with 256 possible values; it currently is defined for only 32 or 64 values.