I'm hoping one of you wizards out there might be able to help me with this one.
I've implemented IP trunking for a client so as to allow them to reduce their toll call costs between 3 sites (least cost routing / toll bypass - whatever you want to call it). Each site has a PBX (2x Philips, 1x NEC) with 2x E1 cards, one to the PSTN and one to my Cisco 2800 router. The PBX's have been configured with steering codes (3 digit prefix added to the number dialed). I have successfully got internal extensions working properly, i.e. one site dials the extension of another site and it goes over the WAN to the remote PBX and to the user. The major problem I have is the toll bypass; the number is correctly routed to my router and traverses the WAN and is passed from the remote router to the remote PBX, unfortunately the call doesn't get out to the PSTN - I would say it's not getting an outside line. The PBX's are managed by contracting 3rd parties and they tell me they have checked the configuration and everything looks fine and have spent a bit of time on this and they're running out of ideas. I don't know anything about PBX's (and don't really want to know) but I wouldn't have expected this to be that difficult - isn't this what PBX's are designed to do; route calls?
We're utilising all 30 E1 channels and I've configured the router to source it's clock from the line. Given that internal calls work fine, I'm of the opinion that the issue is with the PBX configuration. Has anyone any idea of where the problem might lie - is there something I can suggest the contractors do or check on the PBX's.
Any feedback would be warmly welcomed, as this is holding up the whole project and I don't know what to do next