SIP:Alert-Info header

Alert-Info is handled when received in INVITE

It's for endpoints connected to a non-innovaphone PBX that sends Alert-Info in INVITE.
The heuristic method for handling of Alert-Info is as follows:

An incoming call is tagged as "internal" if either:

• parameter "call-type" is "internal"
• parameter "info" is "alert-internal"
• uri contains "file://Bellcore-dr1/"
• uri contains "internal"

An incoming call is tagged as "re-call" (return from failed blind transfer) if either:

• parameter "call-type" is "callback"
• parameter "info" is "alert-community1"

Otherwise an incoming call is tagged as "external".

Alert-Info is handled when received in provisional response

An outgoing call is tagged as "queued" (call-waiting) if "urn:alert:service:call-waiting" is present in Alert-Info header.

Alert-Info when sending INVITE

The innovaphone PBX does not send Alert-Info in INVITE, since there is no specification of Alert-Info beyond its basic syntax and interpretation is manufacturer specific.