Document: draft-ietf-pmol-sip-perf-metrics-03.txt Reviewer: Suresh Krishnan Review Date: 8/19/2009 IETF LC Date: 8/18/2009 Summary: This draft has a few issues that need to be fixed before publication as a Proposed Standard. Substantial =========== * Section 3 Page 7 "Clock correction SHOULD be suspended during a T1 to T4 measurement interval, unless the time interval accuracy requirement above will be met." I think it is inappropriate for this document to specify normative requirements on other protocols (e.g. NTP). e.g. Something like "A T1 to T4 measurement SHOULD NOT be performed during clock correction, unless the time interval accuracy requirement above will be met." * Section 4.1 RRD The text describing the RRD measurement in the following figure is ambiguous. Why is the RRD measured from the first REGISTER and not from the second one? UA1 Registrar | | |REGISTER | T1---->|--------------------->| /\ | 401| || |<---------------------| RRD |REGISTER | || |--------------------->| \/ | 200| T4---->|<---------------------| | | The text reads "...first bit of the initial REGISTER message *containing the necessary information* (emphasis mine)..." which pertains more to the second REGISTER than the first. * Section 4.6. Hops per Request It is not clear how or where this measurement is performed. The way I see it, this measurement requires co-ordination between the two endpoints and this makes it very different from the other metrics in this document. I think this needs to be highlighted and/or clarified. Minor ===== * Section 4.12.2. Failed Session Completion This does not seem to be used anywhere. Is there a missing metric or is this section redundant? Also this does not seem to be the complement of the Successful Session Completion metric.