On 9/25/11 1:56 PM, Cesar Fiestas wrote:
> Hello
>
> Can anyone post a valid call flow or session that involves a 300 Multiple
> choices message? Thanks
>
Consider a typical case of a proxy/registrar handling an AOR, with
multiple UAs registered to that AOR.
Then the proxy receives a call addressed to the AOR. It can:
- serial fork the call to the registered contacts
- parallel fork the call to the registered contacts
- pick one of the registered contacts and return a 301/302
with it
- return a 300 with all the registered contacts and let the
UAC do the forking
- ...
If it decides to return a 300 with multiple contacts, it can use
q-values to reflect the relative priority of the contacts, just as they
were specified at registration.
UACs MUST be prepared to deal with this. Really stupid ones will fail
the call. Stupid ones will retry once with the first contact in the 3xx.
Reasonable ones will do serial and parallel forking based on q-values
and/or local policy.
And don't forget that when retrying with the returned contacts, you can
get additional 3xx responses.
3261 describes what you should do.
Thanks,
Paul
_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
