[asterisk-users] is encrypted iax safe and secure?

[Cavalera Claudio Luigi]

Hello,
I'm doing some research concerning iax encryption, I haven't find any
clients (softphones or hardphones) which implement so I have not tested
it yet.

There was also this message on asterisk-security mailing list
http://archives.free.net.ph/message/20070507.101933.222987b2.en.html
which got no answers and this makes me think that this iax encryption is
not much interesting for the community.

Anyway, in iax specification there is this statement:
"Only the data portion of the messages are encoded."

Which are the consequences of this, is it true as stated on 
http://www.voip-info.org/wiki/view/IAX+encryption
that
"The calling/called numbers are still passed in the clear over encrypted
IAX, so you are still vulnerable to traffic analysis."
?

If it's true how to deal with this?
Would you consider media payload encryption enough?
Maybe it's better to just forget about iax encryption and consider some
more general approach like using openvpn
http://www.voip-info.org/wiki/view/IAX_OpenVPN ?

This half-encrypted iax encryption doesn't make much sense to me,
therefore I think there's probably something I'm
missing/misunderstanding.

Best Regards,
Claudio


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