Mediation Server doesn't send SIP ACK RRS feed

  • Question

  • Hi all!

    I hope that someone can assist me with this issue.  I currently have an OCS2007 Standard Edition setup, with a Standard Edition server and a Mediation Server.  I've not configured any edge servers.  I've found a PSTN Gateway provider that supports SIP via TCP.  When I make calls, the calls are routed correctly to my provider.  A packet capture shows that the session starts getting setup up.  When the recipient answers, the caller can hear the recipient for about 5 seconds, at which point the recipient drops the call.  From what I've seen in the packet capture, the PSTN gateway provider is sending 200 OK messages back to my Mediation Server, but my Mediation Server doesn't send a SIP ACK back, causing the gateway to close the call.  Also, my Mediation Server is inserting it's internal FQDN in the Contact: field of the SIP packet, when it seems like it should be it's external FQDN.

    I've read all the guides - I am working on a small deployment for a small organization that wants big functionality.  Can someone refer me to a document or provide some assistance on how to appropriately configure a OCS2007 Standard Edition server with PSTN access through an external gateway?

    Thank you!
    Thursday, January 3, 2008 11:07 PM

All replies

  • Hi ng,


    Dont know if this helps but the NIC that you use to talk to your gateway on the mediation server shouldnt be registering in DNS only the internal OCS pointing interface should be. I have also heard of issue with using two interfaces on the same NIC card . This can be fixed by just using the one interface to do both internal and external functions, well that is what I have read.


    You can  change the DNS registration under the TCP/IP properties of your interface that talks to the gateway.




    Friday, January 4, 2008 5:55 AM
  • Chris,

    Thank you for your response!  Right now it is configured with two NICs, each with a single IP.  The NIC hosting the external address does not register in DNS.

    Does this sound like the settings you are describing above?
    Saturday, January 5, 2008 6:50 AM
  • Hi,


    Based on your post I understand that you are trying to connect your Mediation Server directly to a PSTN Gateway provider without using a Media Gateway. If this is correct please note that this is currently not a supported configuration. Please refer to this web site http://technet.microsoft.com/en-us/office/bb735838.aspx for a list of support and tested configurations and media gateways. By using these configurations you will get a smooth ride. We are updating the web site with new configurations and media gateways as they become available.


    best regards



    Saturday, January 5, 2008 4:10 PM
  • If you go into the TCP/IP properties and the register in DNS is unselected you should be fine.

    Are the ports on the same card? I have heard that this can be an issue also.


    The fact the call comes up for 5 seconds is pretty strange. I guess the mediation server is timing out somehow. I think you should post your packet capture for people to have a look it may help.






    Saturday, January 5, 2008 4:16 PM
  • I can't say that I am not frustrated about this.  I don't want to host my own connections to the PSTN - I want this at an outsourced provider both for the reasons of costs and availability.  Are you saying that the only Microsoft-support way to make this work is to buy a Media Gateway that effectively takes the SIP traffic from the OCS server and translates that to SIP that can be used else where?  Seems cumbersome.

    There must be a better, less expensive way than this.  What is Microsoft's recommendation for businesses like mine that want the connection to the PSTN outsourced?
    Saturday, January 5, 2008 6:34 PM
  • I have to agree with the other post. If you are not connecting to a PSTN gateway such as a Cisco ISR router or other supported gateway you are going to run into support issues and is probably the reason you are having problems to start with. I would suggest to interface to your serivce provider via one of the gateways listed by MS as supported until they make direct connections to a SIP service provider supported. Sorry I cant be much more help than this.




    Monday, January 7, 2008 4:26 AM