[AVTCORE] Review of draft-ietf-avtcore-aria-srtp-00

Eric Rescorla <ekr@rtfm.com> Mon, 05 November 2012 18:17 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 05 Nov 2012 13:17:02 -0500
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Subject: [AVTCORE] Review of draft-ietf-avtcore-aria-srtp-00
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I have reviewed draft-ietf-avtcore-aria-srtp-00.

I'm leaving aside the question of whether it's useful to define
another symmetric encryption algorithm for SRTP (my view is generally
no, especially since we have already specified SEED)
but the WG seems to have decided that.

With that said I don't really understand why you are defining three
key sizes and three counter modes. I would recommend defining only 128
and 256-bit GCM unless there is some actual reason not to.

Other than that, this seems like a reasonably plausible draft.