Re: [rtcweb] Question about srtp_mki in DTLS/SRTP

Martin Thomson <martin.thomson@gmail.com> Wed, 14 January 2015 01:31 UTC

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From: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [rtcweb] Question about srtp_mki in DTLS/SRTP
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On 13 January 2015 at 17:24, 🔓Dan Wing <dwing@cisco.com> wrote:
> For WebRTC, I don't see SRTP MKI being used.

I'm not aware of anyone using it.  I too would rather prohibit its
use.  That limits two-party session length, but from a practical
perspective, that limit is going to be reached rarely, if ever without
a re-handshake.

Note that EKT isn't a perfect replacement because we should be
prohibiting the initiation of EKT from browser endpoints (well,
applications shouldn't be able to set the value used, though I guess
they could request that the browser initiate EKT).