08 Nov Smart FoIP in Gateways
The wide-scale deployment of V.34 fax terminals is making the design of FoIP-capable IP-PSTN gateways much more of a challenge since V.34 terminals employ a completely different start-up sequence than non-V.34 machines. Moreover, since gateways typically begin calls in G.711 pass-through mode (rather than T.38), V.34-capable endpoints can actually “hear each other” well in advance of the resolution of the SIP signaling resolving the session’s setup. This means the gateways must take an “activist” role to ensure that T.38 is “given a chance” prior to the endpoints going on their merry way, leaving the gateways behind.
Because this technology isn’t widely understood, it’s probably safe to say that there are no T.38 V3 gateways with V.34 support that can actually establish a T.38-based V.34 session outside the lab.
If you’re a gateway developer, you probably know that a called V.34 terminal has a completely different answer tone than a V.17 terminal, and, to make matters worse, it’s the same tone as a V.34/V.90 data modem.And if the calling terminal hears that tone and its response reaches the called terminal prior to T.38 being established, it’s too late for the two gateways to do anything about it. The endpoint machines are off to the races in G.711 mode. If the SIP peers then attempt to switch to T.38, the session will fail. The only hope, then, is for the session to continue in G.711 pass-through mode, where it at least has a fighting chance.
Commetrex’ “Smart FoIP” gives it much more than a fighting chance. With Smart FoIP’s patent-pending technology, even G.711 sessions are reliable. (Yes, you read that correctly.)
So, gateway developers, you need not despair, because Commetrex’ Smart FoIP is here. Smart FoIP handles the four fax-session configurations you need to be concerned about:
- Called GW, V34 fax supported
- Called GW, V34 fax not supported
- Calling GW, V34 fax supported
- Calling GW, V34 fax not supported
And Smart FoIP encapsulates the media technologies you need to do it: V.8 modems, ANSam generation-detection, and call classification…all in one handy module.
There’s only one company with the mantra: “We make FoIP work!”
So, if you intend to do anything about moving to V.34 fax support in your gateway, there’s only one place to go if you want it to actually work.