Skype For Business

 Skype For Business

Skype for Business (formerly Microsoft Office Communicator and Microsoft Lync) is an instant messaging client used with Skype for Business Server or with Skype for Business Online (available with Microsoft Office 365).^[2] Skype for Business is enterprise software.
On 11 November 2014, Microsoft announced that Skype for Business would replace Lync in 2015. The latest version of the communication software combines features of Lync and of the consumer software Skype. There are two user interfaces – organizations can switch their users from the default Skype for Business interface to the Skype for Business (Lync) interface.
In September 2017, Microsoft announced that Microsoft Teams would replace Skype for Business eventually.
On May 20, 2018, Microsoft retired Skype for Business for Windows Phone..

The Basic features of Skype for Business include:

• Instant messaging
• Voice over IP (VoIP)
• Video conferencing inside the client software

Advanced features relate to integration with other Microsoft software:

• Availability of contacts based on Microsoft Outlook contacts stored in a Microsoft Exchange Server
• Users can retrieve contact lists from a local directory service such as Microsoft Exchange Server
• Microsoft Office can show if other people are working on the same document^.
• All communication between the clients takes place through a Skype for Business Server. This makes communications more secure, as messages do not need to leave the corporate intranet, unlike with the Internet-based Windows Live Messenger. The server can be set to relay messages to other instant messaging networks, avoiding installation of extra software at the client side.
• A number of client types are available for Microsoft Lync, including mobile clients.
• Uses SIP as the basis for its client communication protocol^.
• Offers support for TLS and SRTP to encrypt and secure signaling and media traffic
• Allows sharing files

Note: With the release of Lync Server 2013 in October 2012, a new collaboration feature "Persistent Group Chat" which allows multi-party chat with preservation of content between chat sessions was introduced. However, only the native Windows OS client and no other platform supports this feature at this time.^[17] The main new features of this version are the addition of real-time multi-client collaborative software capabilities, (which allow teams of people to see and simultaneously work on the same documents and communications session). Lync implements these features as follows:

• Collaboration through Whiteboard documents, where the participants have freedom to share text, drawing and graphical annotations.
• Collaboration through PowerPoint documents, where the participants can control and see presentations, as well as allow everybody to add text, drawing and graphical annotations.
• Polling lists, where Presenters can organize polls and all participants can vote and see results.
• Desktop sharing, usually by allowing participants to see and collaborate on a Windows screen
• Windows applications sharing, by allowing participants to see and collaborate on a specific application.

All collaboration sessions get automatically defined as conferences, where clients can invite more contacts. Conference initiators (usually called "organizers") can either promote participants to act as presenters or demote them to act as attendees. They can also define some basic policies about what presenters and attendees can see and do. Deeper details of policy permissions are defined at server level.
Following Microsoft's acquisition of Skype in May 2011, the Lync and Skype platforms could be connected, but sometimes only after lengthy provisioning time.

Extensions

Lync uses a number of extensions to the SIP/SIMPLE instant-messaging protocol for some features. As with most instant-messaging platforms, non-Microsoft instant-messaging clients that have not implemented these publicly available extensions may not work correctly or have complete functionality. Lync supports federated presence and IM to other popular instant message services such as AOL, Yahoo, MSN, and any service using the XMPP protocol. Text instant-messaging in a web browser is available via Lync integration within Exchange Outlook Web App.
Although other IM protocols such as AIM and Yahoo! do have wider support by third-party clients, these protocols have been largely reverse-engineered by outside developers. Microsoft does offer details of its extensions on MSDN and provides an API kit to help developers build platforms that can interoperate with Lync Server and clients.