[asterisk-dev] Provider requires Delay between OK and ReINVITE

[Mark Michelson]

On 08/23/2012 06:22 AM, John R. Covert wrote:
> Thanks, Olle.  I definitely want to get directmedia going if possible,
> and I appreciate your opinion as the main SIP developer that such a
> change would be acceptable for the code base.
>
> Thanks to Mark M as well.  I especially appreciate your opinion
> that the provider's equipment is broken (that was my opinion as
> well) and that developing a "directmediadelay" option might only
> avoid one specific issue and set things up for future problems.
>
> Paul, this is why I wrote to asterisk-dev, not to asterisk-users.
>
> While I am an adamant opponent of "Answer"ing calls before a
> "chargeable" event occurs, i.e. if we are going to ring a human
> or other destination which might not answer or be busy (and had
> already tried "Progress" before the delay with no improvement),
> in the _specific_ application _immediately_ at hand, a chargeable
> event will always occur (an IVR in either the main or a bridged
> machine) so the "Answer" is a workaround until I have a different
> application with this provider.
>
> Based on Mark's feedback, I'm going to continue to push on the
> provider for them to eventually fix their problem.  I've already
> asked them to show me where in the SIP RFC a requirement for any
> sort of delay appears.
>
> Thanks to everyone.
>
> Regards/john
I'm not sure which version of Asterisk you're using, but in 1.8, the 
Answer() dialplan app takes two arguments. One is a delay and the other 
is an option to not answer the CDR. Both of these seem like things you 
could make use of in your situation.

Answer(500,nocdr)

If you do that, then Asterisk will answer the incoming call, wait 500 
milliseconds, and will not mark the CDR as answered yet. This can be 
useful if you're going to be making an outbound call to someone else. 
When that outbound call is answered, then the CDR should get marked as 
answered.

You may want to experiment with this to be sure that the CDR gets marked 
correctly when using the "nocdr" option for Answer() and that the 500 ms 
doesn't cause a jarring "blip" in the ringing audio sent to the caller.

Mark Michelson