[Freeswitch-users] FS to answer a call with ZRTP and do text-to-speech of SaS

[Jason White]

Fabio Pietrosanti (naif) <lists at infosecurity.ch> wrote:
> Hi all,
> 
> i would like to call from the product my company is going to release 
> (www.privatewave.com, mobile voice encryption with ZRTP for Nokia, 
> iPhone, Blackberry, Android) a FS extension and, without the ZRTP 
> enrollment, having the extension to be answered negotiating ZRTP and 
> playing with Text to Speech the SaS .
> 
> Is this possible with current FS/ZRTP integration?

Possibly, but you'll have to deal with licencing issues first associated with
the ZRTP library. It's under the GNU AGPLv3 licence, as I recall.

ZRTP is negotiated whenever the RTP stream starts; there's no point delaying
it. If there's no ZRTP support on the other end, it just continues as an
unencrypted call.