VoIP tunnelling using Asterisk


I would like to know if I could use Asterisk for my below given scenario, if yes, how?

SIP Client <--------SecureSIP----->Asterisk (As VPN Tunnel / Tunnelled Proxy)<-----SIP-----> SoftSwitch
SIP Client <--------SRTP----->Asterisk (As VPN Tunnel / Tunnelled Proxy)<-----RTP-----> SoftSwitch

I already have setup Android SIP client which works fine with the softswitch, and I want to add Asterisk as SIP Proxy (Tunnelled) so that calls could be established while on ISP which has VoIP blockade.


Maqbul Khan

VPN tunnelling is a function of the OS, not Asterisk. You can use it with Asterisk, but you do not configure it with Asterisk.

Hi David,

Thanks for your response, so basically, I just want to enable tunnelling between my sip clients and switch, any suggestions?


Use a VPN router. Ask on a Linux forum about Linux support for VPNs.

Can asterisk be setup as SIP proxy to work on SIP/TLS and SRTP? and pass calls to another switch?
As far as I know, Asterisk supports SIP / TLS?

Asterisk cannot be set up as a SIP proxy.

Asterisk is a back to back user agent.

Asterisk can be used as a tandem PABX.

Asterisk will always be man in the middle to encrypted media if used as a tandem switch. Incoming and outgoing legs will be encrypted separately.