Lync Server (new Microsoft release of Office Communication Server) is an enterprise real-time communications server, providing the infrastructure for enterprise instant messaging, presence, file transfer, peer-to-peer and multiparty voice and video calling, ad hoc and structured conferences (audio, video and web) and PSTN connectivity. These features are available within an organization, between organizations, and with external users on the public internet, or standard phones, on the PSTN as well as SIP trunking,
For Office Communication Servers and Exchange there was a program for enterprise telephony services to guide customers to the qualified infrastructure that meet rigorous and extensive testing requirements,
Lately we have Open Interoperability Program OIP page for Lync Server 2010 here.
In this page you will find all Microsoft Lync Server 2010 supported IP-PBXs, and the Qualified Direct SIP Gateways, Survivables Branch Appliance, SIP Truking Services and E-911 Service Providers and Partners.