Lync and Cisco Direct-SIP integration RRS feed

  • Question

  • Hi,

      Has anybody done direct-sip integration between Lync and Cisco CUCM?  I am wondering how the media flow will be.

      Say we provide simring on the Lync side :

    PSTN -> Voice GW -> Lync  simring to Cisco --Direct SIP--> Cisco --> IP Phone

      If Cisco IP Phone answers the call,  does media flow  directly between Voice GW and IP Phone?  Or does it go through mediation server or MTP in between?


    Wednesday, March 2, 2011 1:22 AM

All replies

  • Hello Danny,

    In your simultaneous ring scenario, the Media would flow from the cisco system to the cisco phone. When you have simultaneous ring set up, both phone endpoints are rang. When one picks up, it is up to the Cisco PBX/Lync to inform the other phone endpoint that the call was picked up and to cancel the ring. If you pick up on the Cisco phone, Cisco will sent a SIP CANCEL to the Lync client to make it stop ringing and to close down any media negotiation.



    Richard McGiboney, Support Escalation Engineer, Microsoft
    Sunday, March 6, 2011 11:35 PM
  • Hi,

    Sure, I do co-existing deployments every now and then. You can implement simring in several ways. (I have outlined a few options over at my blog at http://tech.rundtomrundt.com/ Look for the posts "Lync in coexistence with cucm part 1-3).

    No matter how you set it up, during the sim ring the call is only signalling, there is no media set up at that point, and it does not use MTP's or MCU's until the voice path is set up. At which point it will use whatever MTP's or MCU needed (if an at all. This will depend on codec setup end-to-end)




    Saturday, May 28, 2011 8:50 PM