Interop Documentation
Office Communications Server 200
Overview
Microsoft Unified Communications Open Interoperability Program
Microsoft and Cisco: Joint Interoperability Support Statement
  Interoperability Support Between Cisco and Microsoft Products in Unified Communications
IM & Presence
Configure XMPP with Gmail
Configure XMPP with Jabber
  Microsoft Office Communications Server 2007 R2 XMPP Gateway
  Troubleshooting XMPP TCP Dialback Issues with the Communications Server XMPP Gateway
  XMPP to Gmail: Unable to Use Presence and IM—the Problem Might Be Google Apps
RESOLVED - OCS 2007 R2 PIC fails against AOL
  Provision Public IM Connectivity (PIC) with Office Communications Server
  OCS R2 XMPP Gateway Deployment for Gmail (Community Content)
  Fixing interoperability problems between OCS 2007 R2 Public Internet Connectivity and AOL IM (Community Content)
  Time to Panic? OCS Users Can Talk with Gmail Users Now (Community Content)
  Microsoft Lync Server 2010 with CUCM 8 (Community Content)
Video
  General video interop with Polycom and Tandberg
Enterprise Voice
  Direct SIP
  Configure OCS 2007 R2 with Asterisk
  Using Asterisk to Detect and Redirect Fax Calls for Communications Server
  Using Asterisk to Supply Standardized On-Hold Music for Office Communications Server 2007 R2
  Add Key-Press Features to Communications Server when Asterisk is the Gateway
  Setting up the Cisco Call Manager 4.2.1 for “Direct SIP with IP-PBX”
Configure OCS 2007 R2 with CUCM 6.x
  Configure OCS 2007 R2 with CUCM 7.x
  Important OCS CUCM Interop Update: RTCP Timer Issue Solved (Community Content)
  Configuring OCS Simultaneous Ring with CUCM 7.1 (Community Content)
  Archive for the ‘Cisco 7.x Integration’ Category (Community Content)
  Avaya SES and Microsoft OCS interoperability (Community Content)
  SIP Trunk
  Configure Broadvox
  Configure Intelepeer
Configure Thinktele
  Enabling Any SIP Phone & Any SIP Trunking Service Provider with OCS 2007 R2 ! (Community Content)
   
Interop News
IM Interoperability Extended Through XMPP and New Partnerships

Microsoft announces the XMPP Gateway for Office Communications Server 2007 R2 that enables interoperability with Cisco Jabber/XMPP and Google Talk, along with new licensing options for Office Communications Server customers to connect with AOL and Windows Live (read the details of the announcement).

Watch Ashima Singhal (Senior Product Manager) and Albert Kooiman (Senior Product Manager) from the Communication Server team discuss Instant Messaging (IM) interoperability between different networks. This video is posted on the Channel 9 Interoperability topic area: Instant Messaging Interoperability extended through XMPP (Jabber).