[bp]

So, I've seen a few discussions of this, and I'm not satisfied with the answer.

I have an SPA-2000 and an SPA3000 at two different locations, and a hosted machine running Asterisk (for long distance and other call distribution tasks).

I'm trying to get the dialplans right so that the SPAs can call each other, but use all other calling services from the Asterisk server. It's not ok to give the user special codes, and it's desirable that soft-fail be possible (ie, if the SPA3000 basically represents a real POTS line, and the SPA-2000 can't reach it via the network, it should use the Asterisk server's call completion to reach the POTS line associated with the SPA-3000 line).

Everything on Asterisk says to set "canreinvite=no" for SPAs. But, it sounds like that's only really necessary for SPAs behind NAT - all of the given SPAs are on the same network.

Any suggestions? Currently, the SPAs both register to the Asterisk server, which does call routing. But, even though there's no "transfer" permission set on any of the Dial() commands in Asterisk, Asterisk stays in the call pathway when a call is answered.