[VOIPSEC] RTP packet signature

[Hadriel Kaplan]

Depends on what you want to decode - SRTP only encrypts the codec payload
(and optionally adds an MKI and auth tag).  But the RTP headers are left
alone.  So you could use the same techniques to decode an SRTP stream as you
would an RTP stream.  

Obviously it would be very difficult to decode the codec for playback
though. (although I wonder how difficult for g711, given all the redundant
bytes in the codec payload during silence)

-hadriel


-----Original Message-----
From: Voipsec-bounces at voipsa.org [mailto:Voipsec-bounces at voipsa.org] On
Behalf Of Haluska, John J
Sent: Wednesday, October 05, 2005 1:52 PM
To: mailinglist at pbxnsip.com
Cc: Voipsec at voipsa.org
Subject: Re: [VOIPSEC] RTP packet signature

I had the impression that the original question was regarding a third
party, not the intended recipient (who would have had access to the
signaling protocol). Third party would also not be able to decode the
packet if it's SRTP.