Re: [rtcweb] Retransmit: Summary of Alternatives for media keying

[Hadriel Kaplan <[e-mail]>]

On Jul 29, 2011, at 8:59 AM, Randell Jesup wrote:

> No disagreement at all.   I'm discussing that DTLS-SRTP is vulnerable 
> (to a degree) to MITM
> attacks, which is well-known, if you don't have a known-secure signaling 
> channel.  I'm not making the
> argument that Hadriel is.
> 

But that *is* the argument I was making. (or at least trying to :)  
I certainly wasn't claiming SDES nor RTP are as secure as DTLS-SRTP could be.

What I said to start this whole thing was: the two alternatives should not be described as choosing between secure and insecure.  BOTH alternatives require the user to verify something for the call to be secure.  BOTH alternatives have the potential to be very secure.  That is all.

BTW, I am assuming of course that even if we choose the alternative of DTLS+SDES+RTP, that DTLS would always be preferred, and if the peer cannot do it then SDES, and if the peer can't do that then RTP. (assuming the human has set whatever browser knobs are necessary to enable/disable this stuff)
So between two RTCWEB browsers it would always be DTLS-SRTP.

-hadriel