SIPAddHeader(Alert-Info: Ring Answer)

In implementing paging I inject in an extra SIP header to force the phone to automatically answer. This works just fine to use Ring Answer. However, I am wondering if there is just an Answer. As in I do not want ringing at all. I want it to be like an intercom, where the caller can speak immediately and know that sound is coming out of all phones. I tried using SIPAddHeader(Call-Info: answer-after=0) but this did not work. Also, I understand some SIP headers are phone specific (I’m using PolyCom).


Ask the phone manufacturer.

Yeah I wasn’t sure which side of the this was going to be on so I did already cross post to Polycom. At any rate, as a general question, are you aware of what other possible left-hand-side value for the Alert-Info SIP header are? I was searching through the RFC for this header and couldn’t find much about alternative lhs values for it.

Thanks again.