On 7/6/12 1:23 AM, Naarumanchi Kaushik wrote:
> Hi All,
>
> I have two questions:
> 1. When a user calls himself(to the same endpoint), he will get User Busy
> response as his device is already busy. So a User busy response is sent
> based on his device status and not based on comparision between From and To
> URIs. Is this correct?
> 2. If call forward always is enabled for this user, and if he calls
> himself, then giving priority to call forward is correct or not? Should
> this also be a User Busy response?
Your questions are mostly choices an implementer can make.
In general you would not decide an incoming call is from you based on
the From address, because there can be many devices sharing the same
AOR. You could check the Contact address and refuse the call if it is
your own. But that won't work if there is a B2BUA in the call path.
I've been waiting to hear of a possible pathology of this sort:
You call yourself, or call somewhere that is routed back to you. Then
your phone gives you a call waiting indication. You put your current
call (the outgoing one) on hold and answer the incoming call. But then
you hear silence because the caller is on hold. You can then switch
between calls, but one end is always on hold. :-)
Probably we don't hear about this in practice because in general you
won't be able to put the outgoing call on hold to take the incoming call
because the outgoing call still hasn't been answered. (That may not
always be true, depending on what middle boxes are in the call.) But
this may be the answer to your query - if you have an outgoing call that
is incomplete (no 2xx yet), then refuse incoming calls. But ultimately
this is a design decision based on the features of your phone.
Thanks,
Pau
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