[secdir] secdir review of draft-ietf-xrblock-rtcp-xr-post-repair-loss-count-07

Scott Kelly <scott@hyperthought.com> Mon, 22 December 2014 13:53 UTC

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From: Scott Kelly <scott@hyperthought.com>
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Date: Mon, 22 Dec 2014 05:53:09 -0800
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Subject: [secdir] secdir review of draft-ietf-xrblock-rtcp-xr-post-repair-loss-count-07
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I have reviewed this document as part of the security directorate's ongoing effort to review all IETF documents being processed by the IESG.  These comments were written primarily for the benefit of the security area directors.  Document editors and WG chairs should treat these comments just like any other last call comments.

Here’s the abstract:

   This document defines an RTP Control Protocol (RTCP) Extended Report
   (XR) Block that allows reporting of post-repair loss count metrics
   for a range of RTP applications.

Prior to this mechanism, RTCP Sender Reports (SR)/Receiver Reports (RR) contain, among other things, the cumulative number of packets lost. That number doesn’t indicate the data successfully received, because the receiver can apply repair mechanisms to recover data. This document adds reporting for post-repair metrics.

The security considerations seem complete, but I have one nit. Here’s the first sentence:

   It is believed that this RTCP XR block introduces no new security
   considerations beyond those described in [RFC3611]. 

Who believes this? I would simply assert this (remove “It is believed that”), and if I wasn’t comfortable with that, I’d take that as an indication that more analysis is required.