Essentially Lync 2013 is the successor of Lync 2010 but it provides you with a seamless across all platforms and ranges of devices from desktop to web to mobile. What all the features in Lync 2013 focus at is a better collaborative environment which would be more supportive of the cloud architecture.
Starting off with the topology changes, monitoring and archiving were two separate server roles in the previous version but with Lync 2013, they have moved both in the front end server roles and that too as optional features. Support for IPv6 and Skype federation has also been provided. To ensure high availability, Lync 15 bricks have been introduced which is nothing but front end servers that would be used during scale out scenarios. Security is another important feature in this regard support for RBAC custom roles for enterprise has been provided. Protocol validation has also been improved.
The Lync web app has been considerably improved, support has been provided for audio and video in the browsers so users that don’t have a Lync client installed can also participate in meetings which also means that Lync attendee is gone which also reduces the role on the system administration because there is one less role to manage.
Persistent Chat has been introduced which was formerly known as group chat but as the name suggests, with persistent chat, users message history is archived and can be viewed which is of great significance for new comers in the chat room. It collectively provides a list of components:
Not only this but the management tools for persistent chat is also embedded in the Lync Server control panel and can also be accessed using the cmdlets.
Enterprise voice features have been improved; this has been done by improving the routing features such as support for multiple trunks between meditation servers and gateways. Apart from that it now has the capability of manager/delegate simultaneous ringing, voicemail escape and caller ID presentation.
Developer options are a high priority area as far as Lync is concerned so 3 development roles have been provided in it, namely:
1) Lync On premises (a complete on premises model)
2) Lync Online (purely cloud based services)
3) Lync Hybrid (a combination of both of the above)
Multiple new interesting features have been provided in Content sharing ranging from option of adding animations to slides to automatically muting attendees during a video to the ability of viewing speaker notes during a presentation. The look and feel of Office 365 has also been incorporated in it.
Lastly talking a little bit about disaster recovery and high availability, just like the previous version, server pools with redundant roles running are still the primary source of ensuring high availability but one can now pair front-end pools in different data centers so if one pool fails, the administrator can switch over to another pool.