[Freeswitch-users] SIP alaw to SIP T.38 gateway

[Steve Underwood]

On 07/20/2010 11:16 PM, Weera Suriya wrote:
> Hello list,
> I have a question about t.38 fax gateway feature in FS(mod_spandsp).
> here is my setup.
> PSTN <----SS7--->YATE(doesn't support T.38 fax 
> gateway)<----IAX2--alaw---->CallWeaver-Faxgateway<------SIP--T.38------->OpenSIPs<------->ATAs(T.38)<---->fax 
> machines
> I've 16 E1s connected with my Yate server and Yate server send faxes 
> to Callweaver servers (6 servers for CallWeaver) via IAX2(alaw) . then 
> CallWeaver servers send faxes to OpenSIPs server via  SIP T.38 and 
> OpenSIPs server send SIP calls to ATAs
>
> Now I want to expand this setup by adding 16 more E1 connections and I 
> want to replace these 6 CallWeaver servers with one or two FreeSwitch 
> :) I would like to know one thing. does FS able to convert SIP alaw 
> fax (or IAX2 alaw fax) into SIP T.38 fax (I know TDM to SIP t.38 works 
> with FS)
>
We have T.38 gateway functionality implemented in FS now. At this point 
it should be more robust than Callweaver in its call negotiation logic, 
and the logic in the T.38 engine. However, it has not yet been pushed as 
hard as Callweaver with concurrent channels. The design looks good, but 
we still need to prove no processing spikes, or similar issues, prevent 
the concurrent channels going right up to the limits of the processors. 
If you want to try high volumes with FS we will be grateful for any 
feedback, and I will consider addressing any performance issues you 
might find a priority.

Steve