[Freeswitch-users] Transcoding and TLS Handling Proxy

[Adam Sherman]

Good Morning,

I have an existing SIP-based hosted PBX service running on a commercial platform. To handle some edge cases, I would like to setup a proxy to achieve two purposes: transcoding from iLBC, SILK & G.722 to G.711 and offering SIP over TLS and SRTP to customers that require it. I was originally looking to see if OpenSIPS could do this, but I now believe this is better achieved by a B2BUA and thus FreeSWITCH (please comment on that logic).

Some key points I have found, so far:

1. Since the proxy will be transcoding and/or handling SRTP streams, it will also need to handle NAT traversal;

2. It should be completely stateless, I think;

3. UACs will be registering through it (they will be configured with it as an outbound proxy);

4. If one UAC ends up being connected to another UAC (e.g. extension to extension dialling), we want the SRTP stream to simply be relayed;

5. This proxy will simply relay all signalling and decrypted/transcoded media to the existing switch;

6. If I run into scaling issues, I can use Sangoma's hardware transcoding solution with FreeSWITCH;

It would be great to hear all your comments and suggestions of what components and modules to use and any other tidbits you can provide.

Also, if anyone has done something like this already and wants to offer commercial services to replicate it for me, send me an email.

Thanks,

A.

-- 
Adam Sherman
Technologist
Deputy SARCOM, SAR Global 1
Coordonnateur de L'AQBRS, région 07 Outaouais
+1 613 797 6819