[Freeswitch-dev] Implementing preferred channel selection in freetdm using sangoma isdn ?

[Michael Jerris]

It's not setup to do that right now, as you found.  I'm not sure how invasive the changes may be to do this.

On Jul 15, 2014, at 3:26 AM, Matteo <mbrancaleoni at voismart.it> wrote:

> Hi,
> 
> the following applies to ftmod_sangoma_isdn.
> 
> Scenario:
> some pri isdn switches does not like exclusive channel selection,
> but needs the setup message to carry a preferred channel selection ie.
> 
> Adding this in freetdm (in setup message) and making it configurable
> is easy and an example patch is attached.
> 
> BUT!
> 
> If the remote switch changes the channel, we need to "move" the current
> freetdm channel to the one specified in the provisional response or setup ack.
> 
> According to q.931 is wrong to allocate a b channel before having
> confirmed the right one to use, but right now freetdm allocates it immediately.
> (maybe is worth changing that?)
> 
> So, I'm trying to understand all the stuff between freetdm and ftmod_sangoma_isdn
> in order to modify it and make the preferred b channel selection working.
> 
> Any hint ? Which is the best way to "swap" a freetdm channel or move to another?
> Is something the stack already allows or needs some major modifications?
> 
> mat<pri_exclusive.diff>_________________________________________________________________________