On Jan 15, 2008 6:11 PM, Scott Lawrence <[EMAIL PROTECTED]> wrote:

> Why both instead of just using one or the other?

Actually, we've recently been seeing this a fair bit with "number
unavailable" on mobiles here.  One paticular mobile carrier has
recently got in to the habit of sending ringing indication, followed
by a "The person you are calling is currently unavailable.  Please try
again later, or send a text." as early media. urgh.

To work around it, we've started mapping this to a 183 and generating
in-band ringing on our PSTN gateways to stop confusing a number of
broken SIP UAs.

Obviously this particular example is not a long term problem due to it
being simply an impedance mismatch between SIP and the PSTN, but that
is absolutely no excuse for UA implementers to handle incorrectly what
is a perfectly legal scenario!!

 ~ Theo
_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors

Reply via email to