Subject: [secdir] Secdir review of draft-ietf-xrblock-rtcp-xr-decodability-09

From: Catherine Meadows <[email-masked]>
Date: Fri, 8 Mar 2013 18:45:22 -0500

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.

This ID concerns a new RTP  Control Protocol Extended Report Block that reports decodability
statistics metrics for RTP applications using MPEG2 TS over RTP.   These are parameters necessary or helpful to
ensure that TS transmissions can be decoded.  This includes information
such as transport stream synchronization losses, sync byte errors, and continuity count errors,  and others,  apply to all MPEG2 applications.
The ID gives the format for each of the parameters in the Report Block.

The authors of the document point out in the Security Considerations section that the ID introduces no new security considerations
beyond those  described in RFC 3611.  RFC 3611 describes RTP Extended Reports Blocks in general.  The security considerations discussed
are that the information  in the Report Blocks, which are generally unencrypted, could reveal confidential information, and that an attacker
could possibly take advantage of the size of the Extended Report Blocks to launch a denial of service attack.  I agree that the Report Blocks described
in this ID to not introduce any security considerations beyond that, and thus do not believe that this ID needs any further  examination from
a security point of view.

Cathy

Catherine Meadows
Naval Research Laboratory
Code 5543
4555 Overlook Ave., S.W.
Washington DC, 20375
phone: 202-767-3490
fax: 202-404-7942
email: [email-masked]