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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>All,<o:p></o:p></p><p class=MsoNormal>I hadn’t looked into the convergence layers section of the draft BPv7 blue book [1] earlier, and understand that these comments are coming late in the draft process.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The requirements in Section B2.1.4 “LTP Convergence Layer Adapter” currently don’t actually specify which LTP Client Service ID is to be used for this CLA and because this “multiple bundles within a block” encoding scheme is different than what is defined for Client Service code point 1, I think that a new Client Service code point needs to be allocated for this encoding. It would also be valuable for a decoder to understand whether this encoding form allows only BPv7 bundles to be present or also v6 (or even a mix of the two). These are all considerations that if left unspecified will lead to interoperability failures.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Separate from the Client Service ID, the notion of a “length prefixed set of bytes” within CBOR is actually how the byte string major type [4] operates and this encoding seems like it would be better understood by encoders and decoders as a byte string type. In fact, this pattern of CBOR-within-byte-string is common enough that there is both CDDL schema for it as well as CBOR diagnostic notation for it. This second comment is less of an interoperability issue and more of a way to stick to existing tooling conventions for handling bstr-embedded CBOR.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The CDDL for this would be something like:<o:p></o:p></p><p class=MsoNormal style='margin-left:.5in'><span style='font-family:Consolas'>bp-in-block = (+bundle-bytes) ; encoded as a CBOR sequence<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span style='font-family:Consolas'>bundle-bytes = bstr .cbor bundle<o:p></o:p></span></p><p class=MsoNormal style='margin-left:.5in'><span style='font-family:Consolas'>; where “bundle” symbol is from Appendix B of </span>RFC 9171<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>and the diagnostic notation is to enclose items with “<<” and “>>” brackets [5].<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks for any consideration,<o:p></o:p></p><p class=MsoNormal>Brian S.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>[1] <a href="https://public.ccsds.org/review/CCSDS%20734.2-P-1.1/734x2p11e1.pdf">https://public.ccsds.org/review/CCSDS%20734.2-P-1.1/734x2p11e1.pdf</a><o:p></o:p></p><p class=MsoNormal>[2] <a href="https://www.iana.org/assignments/ltp-parameters/ltp-parameters.xhtml#client-service-ids">https://www.iana.org/assignments/ltp-parameters/ltp-parameters.xhtml#client-service-ids</a><o:p></o:p></p><p class=MsoNormal>[3] <a href="https://sanaregistry.org/r/ltp_serviceid/">https://sanaregistry.org/r/ltp_serviceid/</a><o:p></o:p></p><p class=MsoNormal>[4] <a href="https://www.rfc-editor.org/rfc/rfc8949.html#section-3.1-2.5">https://www.rfc-editor.org/rfc/rfc8949.html#section-3.1-2.5</a><o:p></o:p></p><p class=MsoNormal>[5] <a href="https://www.rfc-editor.org/rfc/rfc8610#appendix-G.3">https://www.rfc-editor.org/rfc/rfc8610#appendix-G.3</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>