BRI/S-Bus FAX Server with SIP Trunk 1

[Maerad]

Hi guys!

Tomorrow we change our phone line from ISDN to SIP. After some help from here, the SIP Trunk itself works fine and we can already call out. No problems so far...

But I missed something really important - our FAX...

Not the analogue faxes, those should work fine with SIP and I already found the guides for it. My real problem is, that we have a FAX Server (Windows) with an ISDN USB connector going over a special S0 converter/cable to the BRI. Offical cables from Avaya, nothing self made.

Internal Fax Number 40
External Fax Number 50

(needed because of old fax machines)

Current Config:
Lines ISDN FAX
- BRI Card 3, Port 12
- Incoming Group 11, Outgoing Group 12
- Type: S-Bus

SIP Trunk:
- Line Number 100 (incoming/outgoing)
- FAX set to G.711
- Option G.711 FAX ECAN enabled

Incoming Call Routing:
- ISDN Line(s) (Group Number 0)
- external Number 50 routed to internal number 40 (one of our analogue faxes still has number 50 and I want to reroute everything to the fax server)

Function Code:
40, DIAL, Line 12

Fax Server CAPI:
- EURO ISDN
- MSN 40
- nothing special, everything standard

Incoming faxes shouldn't be a problem, I already have another SIP Trunk that uses the FAX Server with incoming connections. That's why I assumed somewhere in my head, the outgoing connection shouldn't be a problem too. But now I face the problem, that I don't really get HOW I can enable the S-Bus to work with the SIP Trunk...

Any ideas?

 

[ipohead]

I've only been briefly involved in this but I understand the SBus + converter is basically a crossover with some terminating resistors so it need an active ISDN trunk to work.

There no actual conversion from SIP to ISDN unlike say analogue extensions which still work if you change from ISDN trunks to SIP.

 

[janni78]

You can call from SIP to PRI so why not SIP to BRI?

Do a Monitor trace to begin with, what happens when it tries to dial out?

"Trying is the first step to failure..." - Homer

 

[Maerad]

You can call from SIP to PRI so why not SIP to BRI?

Do a Monitor trace to begin with, what happens when it tries to dial out?

That's the main problem - I don't know HOW I can get the ISDN S0 to dial out over SIP. Right now the converter is patched between the fax modem an the BRI. I didn't create a User or Phone for it. Simply added a function code (40, call, 40, Line 12 (the ISDN BRI)) so I could route the incoming calls to the fax server msn. And I added the MSN in the capi driver of the fax server of course.

Any idea how I can get the "S0" to dial over the SIP Trunk and not over the ISDN lines?

 

[amriddle01]

It will match system shortcodes, just like a handset would, so if system shortcodes route to the SIP so will it. You may have a line shortcode taking priority in the SO line settings, so check that

 

[Maerad]

Hi guys!

It works! Here's what I did:

Function Code:
40, dial, 40 > Line 12 (the S0 Port, so didn't change anything here)

Line Setup:
S0-Bus, Line 12
Function Code:
? / Faxdial / . / 100 (SIP Trunk)

I'm still playing around a bit, till I get used to the new stuff. Will post any changes / problems I encountered here (back then I added a ISDN 3100 hz to the analogue faxes as function code, because they had some issues with some other fax machines...). Thanks so much for all the replies :3