Re: [rtcweb] use cases, F20 and encryption, SCTP - comments on draft-ietf-rtcweb-use-cases-and-requirements-07

Martin Thomson <martin.thomson@gmail.com> Sat, 28 April 2012 03:51 UTC

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Date: Fri, 27 Apr 2012 20:51:05 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Dan Wing <dwing@cisco.com>
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Cc: rtcweb@ietf.org, draft-ietf-rtcweb-use-cases-and-requirements@tools.ietf.org
Subject: Re: [rtcweb] use cases, F20 and encryption, SCTP - comments on draft-ietf-rtcweb-use-cases-and-requirements-07
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> 1. Requirement F20 states:
>
>   F20  It MUST be possible to protect streams from eavesdropping.
>
> Consensus in the room during my presentation to RTCWEB at IETF83 was that we
> don't need to support un-encrypted media (RTP) at all, and that all media
> would be SRTP.  Can that be captured in F20 by re-wording, or perhaps in a
> new requirement if we can't reword F20?  If there is a need or desire to
> validate that consensus on list, let's please ask the chairs to do that.

This requirement probably requires a bit more examination.  I tend to
agree that something more specific regarding SRTP would be good, but
that doesn't cover the whole story.

SRTP alone doesn't protect against the site (or sites).  If there is
mutual authentication, then it might be possible to prevent an
application from being able to eavesdrop (conditional on some degree
of trust in the identity provider).