Microsoft/Cisco Interoperability Choices

The unified communications sector is in a constant state of change. With each passing day, vendors seem to come out with new products. With these new or improved products come new interoperability options. When Microsoft’s Office Communications Server first arrived on the scene, interoperability with vendors like Cisco was limited but now with updates, OCS direct connect is viable option along with others. So what options are available for interoperability with Cisco Communications Manager (CUCM)?

SIP direct connect (OCS Mediation server -->SIP--> CUCM)

IP-IP Gateway (OCS Mediation Server -->SIP-->ISR or other device-->SIP/H323-->CUCM)

TDM Gateways back to back or TDM gateway to PBX (OCS Mediation Server-->SIP-->TDM Gateway-->T1/E1-->PBX)

Remote Call Control (OCS/LCS-->SIP/CSTA-->CUPS-->CTI-->CUCM)

There is a bunch of information on the web about direct SIP and RCC so for the next few blogs at least I will concentrate on using a Cisco ISR setup as an IP-IP GW(other vendors also have similar solutions). For large enterprises, this option can be attractive to allow a more scalable solution. It also removes compatibility issues and depending on the setup can allow a straightforward setup in CUCM. The IP-IP GW can enable OCS to CUCM (all versions) but also CUCM (4.2.3) to Exchange 2007 Unified Messaging.

Tip of the Day:

For those not familiar, the following TechNet forum offers an excellent source of information to supplement documentation and ask questions related to OCS telephony.

http://social.microsoft.com/forums/en-US/communicationsservertelephony/threads/