Microsoft Lync Server ( previously Microsoft Office Live Communications Server )

Microsoft Lync Server ( previously Microsoft Office Live Communications Server )
http://lync.microsoft.com

http://en.wikipedia.org/wiki/Microsoft_Office_Live_Communications_Server
Microsoft Lync Server (previously Microsoft Office Communications Server) is an enterprise real-time communications server, providing the infrastructure for enterprise instant messaging, presence, file transfer, peer-to-peer and multiparty voiceand video calling, ad hoc and structured conferences (audio, video and web) and, through a 3rd party gateway or SIP trunk,PSTN connectivity.^[1] 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.