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Re: [rtcweb] Which servers to trust (Re: Consensus call regarding media security)

Iñaki Baz Castillo <ibc@aliax.net> Tue, 03 April 2012 11:55 UTC

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From: Iñaki Baz Castillo <ibc@aliax.net>
Date: Tue, 03 Apr 2012 13:55:38 +0200
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To: Harald Alvestrand <harald@alvestrand.no>
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Cc: rtcweb@ietf.org
Subject: Re: [rtcweb] Which servers to trust (Re: Consensus call regarding media security)
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2012/4/3 Harald Alvestrand <harald@alvestrand.no>:
>> SDES-SRTP provide a very reliable and simple way to let a WebRTC peer to
>> establish security with the server, assuming that it already have
>> established security trough HTTPS/TLS that's a consolidate trust method.
>
> The term "the server" is a fallacy. The Web server and the media gateway (if
> there is one) are likely not the same server, and may even be operated by
> different entities.
> SDES-SRTP forces you to trust both.


If you trust the Web server (i.e. due to HTTPS usage with a valid
server certificate) then you will also trust that the Web server will
not signal your WebRTC communication to a malicious destination, am I
wrong?

Don't take me wrong but, which kind of security obsession are we
trying to satisfy in rtcweb? a media communication is not more
important than a web access to my back website in which I enter my
credit card PIN. Does IETF define "security standards" for POS ("Point
of sale terminal") for making a bank payment via a 3rd web
(e-commerce)? AFAIK not.

If the Web server (assuming HTTPS) is trusted and SDES-SRTP used, we
should trust the communication. If it fails that is because the Web
server has been attacked. If that occurs, it's really worse the case
in which my bank website has been attacked (I'm giving my credit card
PIN to the attacker).


Regards.


-- 
Iñaki Baz Castillo
<ibc@aliax.net>

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