[Freeswitch-users] How to call multi gateways for failover with early media?

[David Knell]

On Sat, 2009-04-04 at 03:32 -0400, Kristian Kielhofner wrote:

> 
>   180/183 with SDP is a bit ambiguous.  I always get frustrated when
> various people /insist/ on using 183 w/ SDP just for ringback.  Have
> they never heard of 180 w/o SDP?  Let me generate my own local
> ringback and/or handle the situation accordingly!

Ah, well, that's where you're trying to change the way that things
have been done for some decades.  Ringback has historically been
generated close to the called party, which is why you hear different
ringback if you call people in different countries.

Furthermore, that audio path is used to convey all sorts of messages:
"the number you have called has been changed", "the cellphone you have
called has not responded", "calls to 1-800 numbers are not free if 
made from overseas.."  Lastly, there's no guarantee that it'll be
possible to differentiate between one of these and ringback from the
signalling alone and, in many cases, there is simply no mechanism 
available to provide such differentiation.

You're probably best advised to swim with the tide on this one..!

Cheers --

Dave