SIP is the IETF's answer to the ITU's H.323. It's very similar in design to HTTP and most major enterprise telephony infrastructure providers have been migrating to it at some non-trivial pace. Of course, the big problem with SIP is your SIP and my SIP aren't always the same. This is becoming less of a problem as more folks deploy it, but if you look at how Cisco bastadized the SIP implementation on the line side of their IP PBX, you'll know what I mean: lots of proprietary extensions to make the various line-side features working.
Heh. I know what SIP is. I've done a lot of telco programming. What I meant was, in what way do you want twilio to support sip? I'm sure it's what they're using on the backend, with a sip trunking provider (or multiple)...
Is there a reason to want them to send SIP rather than calls over the PSTN? If you want SIP, using a hosted solution may not be the answer...
SIP is the IETF's answer to the ITU's H.323. It's very similar in design to HTTP and most major enterprise telephony infrastructure providers have been migrating to it at some non-trivial pace. Of course, the big problem with SIP is your SIP and my SIP aren't always the same. This is becoming less of a problem as more folks deploy it, but if you look at how Cisco bastadized the SIP implementation on the line side of their IP PBX, you'll know what I mean: lots of proprietary extensions to make the various line-side features working.