Calling over ISDN RRS feed

  • Question




    I'm new to OCS and i want to build a working environment.

    I have a running OCS, an isdn-card inside my OCS and a isdn-connection.

    Now I want to call the rest of the world with my Linksys SPA-921 telephones.

    How could I connect the telephones to the OCS and how should I set up the OCS to make a call over the isdn-card?

    Could someone help me?

    I'm sorry if there is a thread with this question - but i havent found one.


    Kind Regards


    Sunday, May 25, 2008 10:37 AM

All replies

  • Hello and welcome,

    your path to success will be long and rocky, young Padawan. Wink

    Let’s say your goal is really a challenge, but not impossible I guess. I hope you have some time, patience and a suitable budget. I assume that you like to run everything on one machine? If you have any additional server hardware, please use it when you plan to create a productive environment.

    Please note: The following one machine setup is not recommended and I cannot guaranty you that it will work. But I think it is worth trying it, for a lab or demo environment.

    1.       Your phone’s SPA-921 cannot register at OCS 2007. (If you need more details why, please ask for it.)You need a IP-SIP-PBX were they can be registered.

    2.       This IP-SIP-PBX should be compatible with your SPA-921 and able to interact with the OCS Mediation Server (a special role of OCS), and if you like Exchange2007 UM server too.
    I recommend using the IP-SIP-PBX
    pbxnsip. You can get a free trial version with all features for testing – the only limitation is the call-length (3 minutes), as long as you don’t buy a license key.

    3.       If you owned a ISDN card like the Dialogic DIVA V-BRI-2 or 4 and the dedicated SIPcontrol Software you have a good ISDN to SIP basic system. If your ISDN card does not support any additional SIP software, for translating ISDN to SIP you should try to get a Dialogic, including SIPcontrol. Or you run everything in SIP, by configuring a trunk to a VoIP-Provider in pbxnsip.

    4.       You need to run two virtual machines (windows 2003) on the same physical server, were you installed OCS2007. One for pbxnsip and one for the OCS Mediation Server. You can use VirtualPC or Virtual Server for this.

    Your deployment layout will look like this:

    ISDN <–> DIVA-ISDN-Card <-> SIPcontrol <-> pbxnsip(VM) <-> OCS Mediation Server(VM) <-> OCS Standard Edition

    For configuring OCS 2007, OCS2007 Medation Server and pbxnsip please carefully read my Wiki-page:

    Basic Setup for pbxnsip / Office Communications Server 2007 Interoperability

    Divergent from my guide you can configure a trunk in pbxnsip to SIP-Control, which is nothing else than a voip-gateway. The setup steps are similar.

    Note: There will be some pitfalls in your way. If you need any additional help, simply ask for it!

    Best regards,


    Monday, May 26, 2008 3:44 AM