Re: [secdir] sec-dir review of draft-ietf-avt-forward-shifted-red-05.txt

Qiaobing Xie <> Mon, 19 July 2010 17:06 UTC

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Date: Mon, 19 Jul 2010 12:07:05 -0500
From: Qiaobing Xie <>
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Subject: Re: [secdir] sec-dir review of draft-ietf-avt-forward-shifted-red-05.txt
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Thanks for the comments. I will try to reword the security section to 
make it more readable when I update the draft.


Derek Atkins wrote:
> Hi,
> 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 document defines a simple enhancement to RFC 2198 to support RTP
>    sessions with forward-shifted redundant encodings, i.e., redundant
>    data sent before the corresponding primary data.  Forward-shifted
>    redundancy can be used to conceal losses of a large number of
>    consecutive media frames (e.g., consecutive loss of seconds or even
>    tens of seconds of media).
> The security considerations section is not written in gramatically
> correct English.  While this reader was able to decipher the meaning,
> I hope that someone with more editorial capabilities can massage the
> text into actual correct English sentences.
> Beyond the editorial issues, the document does address the single
> issue I see, which is the potential denial of service attack where the
> sender sends bogus forward-shifted data, potentially claiming large
> buffers in the receiver.  Once the security considerations section is
> cleaned up it will more clearly state that "outrageous values" should
> be ignored.
> -derek