the server, client application & SDK designed for use with Microsoft Lync Server (or Office 365 Online) to provide Instant Messaging, audio/video, file and desktop sharing features to organisations.
Microsoft Lync (formerly Microsoft Office Communicator) and Microsoft Communicator for Mac are instant messaging clients used with Microsoft Lync Server or Lync Online available with Microsoft Office 365 and Live@Edu. They are replacements for Windows Messenger which was used with Microsoft Exchange Server.
Both Microsoft Lync and Microsoft Communicator for Mac are enterprise software, requiring connection to either an on-premise Lync Server instance, or a server instance in-cloud, such as Office 365.
The Lync client contains a contact list of contacts, along with their Presence status. Presence is automatically updated according to Outlook calendar activity, keyboard locking, making or receiving a AV call etc.
Lync supports a number of modalities, including IM, Audio, Video, Desktop Share, File Share. There is some low-level provision to extend this to add custom modalities.
A typical Lync installation will extend Outlook, Sharepoint and Dynamics CRM to presence-enable any Lync contacts displayed. Microsoft have also made available Silverlight/WPF controls to allow developers to Lync-enable custom applications easily.
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