Hi,

I have an application where answering an incoming call and establishing
outbound audio is required in the shortest possible time.

Using wireshark on my application the timing is

0ms         INVITE
3ms         100 Trying
123ms    180 Ringing
132ms    200 OK with SDP
134ms    First RTP/RTPC

In my code I process a variety of events, including

CALLSTATE_NEWCALL  - I respond with sipxCallAccept
CALLSTATE_OFFERING - I respond with sipxCallAnswer
CALLSTATE_ALERTING - I don't respond.

In all cases I respond as quickly as possible - however I have
duplicated the event and am responding to the duplicate on a processing
thread rather than original event on the API thread.

My question is whether the internal sequence NEWCALL/OFFERING/ALERTING
has API-side timers? If so, are they tweakable? My target is low 10's of
milliseconds to first RTP.

Alternatively, are there hooks that allow mic audio to be intercepted
outside of the call context?  This is so I can delay audio slightly till
the call is established and normal processing ensues. I know about the
in-call audio hooks but that doesn't help me while the call is
establishing. In my case every millisecond of audio is valuable but it
can be delayed slightly without problem.

Thanks in advance

Jeremy

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