Tag Archives: Skype for Business Server Roles

Video Interoperability Server

Video Interoperability Server (VIS) is a new server role which has been introduced in Skype for Business (SfB) Server 2015. VIS will simplify interoperability between SfB infrastructure and legacy Video Teleconferencing Systems (VTCs).

Video Teleconferencing Systems (VTCs): Typically Video teleconferencing devices has been used in conference rooms and come up with one or two screens. Few expensive VTCs come up with MCUs which can host the conferences. Cisco/Tandberg VTCs support SIP, H.323 and support SDP for negotiations while support RTP/RTCP and H.264 AVC codec for media.

Legacy Cisco/Tandberg VTCs was the enormous concern for many customers because they were using large number of VTCs in their premises. To overcome this concern, Microsoft has built a new standalone server role called Video Interoperability Server (VIS) in SfB. VIS is a scalable server role which eliminates the need of third party infrastructure to between legacy VTCs and SfB infrastructure.

With the help of VIS, VTC can join the conference meeting as an audio/video endpoint and be displayed in the video gallery to provide the consistent and familiar experience to end users. It can also be used for peer to peer calls. Lync Server 2013 can also take advantage of VIS with SfB deployment, SfB registrar pool will be the next hop for VIS. In the same way VIS is the next hop from CUCM also. VIS sends media to VTC directly, does not support media bypass and VTCs cannot become an ICE candidate behind Edge.

VIS doesn’t support transcoding of video streams. Therefore, Lync 2010 client can’t be displayed on VTC via VIS and vice-versa because Lync 2010 supports RT Video and VTC supports H.264. Lync 2013 and SfB clients can communicate with VTCs via H.264.

VTCs can dial into conference via CAA while drag-and-drop option is not supported. VIS only supports one way call from VTCs to VIS, calls from VIS to VTC is not supported. Application sharing and Telepresence Interoperability Protocol (TIS) is also not support but later can be added.


Difference between Lync Server 2010, 2013 & Skype for Business Server

Skype for Business Server 2015 is a next major release after Lync Server 2013. There is no major architecture level change from the previous release. Skype for Business Server is coming up with many improvements and one new server role “Video Interop Server (VIS)” has been added which will work as an intermediary between third-party video teleconferencing system and Skype for Business Server infrastructure.

Below table gives you a high-level overview of difference between Lync Server 2010, Lync Server 2013 & Skype for Business Server roles.

You can collocate Persistent Chat Server role In Lync Server 2013 & Skype for Business Standard Edition. In Lync Server 2010 A/V Conferencing, Archiving & Monitoring Server roles can be deployed as a stand-alone pool or can be collocated with Front End Server. Skype for Business Server SQL Back End supports all the SQL HA options available such as Mirror, Cluster and Always-On while Lync Server 2013 doesn’t support SQL Always-On.

There are many improvements which has been done in Skype for Business, please stay tuned with me to know more about improvements in detail.


Skype for Business Server Roles

Skype for Business Server 2015 has all the roles which were part of the Lync Server 2013 and comes with SQL Server 2014 Express edition. The new server role “Video Interop Server” has introduced in Skype for Business Server 2015 which will act as an intermediary between Skype for Business server infrastructure and third-part video teleconferencing systems. In this article, will talk about all the server roles which are part of the Skype for Business Server 2015 and collocation of these server roles. Below is the graphical representation of server roles.


Standard Edition Server: Same as Lync Server 2013 Standard Edition Server, Skype for Business Standard Edition Server is basically for small deployments or can be used for branch sites. You can collocate Mediation server or deploy a stand-alone Mediation server according to your design and requirements. Even Persistent chat server also be collocated with Standard Edition Server. Same as Lync Server 2013, if you deploy archiving, monitoring or persistent chat server then you should have dedicated SQL server to deploy their databases.

Front End Server: There are no major changes in Front End Server. Front End Server is a core server role of the entire Skype for Business topology and works in similar way as it was in Lync Server 2013. You can start with minimum three FE servers and can go up to twelve FE servers in a single pool. Same as standard edition server, you can collocate Mediation server with FE pool or can deploy a stand-alone Mediation pool. There are few changes have been done in terms of Windows fabric and services/pool availability which will be written separately in another post. Same as Lync Server 2013, Skype for Business Server Front End pools are the primary store for user and conference data, each user data is replicated among three FE servers and same backed up on Back End Servers.

Back End Server: There are many options which can be used to deploy Back End Servers. Skype for Business support many options to achieve high availability of Back End databases. SQL Server 2012 with SP1 and SQL Server 2014 can be used with SQL Mirror / Failover Clustering or SQL Always-On to deploy Back End Server pool.

Mediation: Same as Lync Server 2013, Mediation server is required to implement Enterprise Voice, Call-via-work, and dial-in-conferencing features. Mediation server works as an intermediary between FE Servers and Enterprise voice setup and facilities signaling and media. In few cases Media can be bypassed but signaling always need Mediation Server component. As discussed earlier, Mediation server can be collocated with FE pool or can be deployed as a stand-alone pool.

Director: Director is still an optional server role or can be deployed as needed. You can have maximum 10 Director Servers in a single pool. Director can simplify your redirection and authentication process if you have multiple pools. It can also save your Front End servers from denial-of-service attack. This role cannot be collocated with any other server role.

Edge Server: Edge Server is require to allow Skype for Business services to those users who are not part of the corporate network, such as users logging remotely. It also allow commination between external/federated users and corporate users. Skype for Business Edge Server works in same way as Lync 2013 Edge Server. This role cannot be collocated with any other server role.

Video Interop Server: This is a new server role which has been introduced in Skype for Business Server. VIP works as an intermediary between Skype for Business infrastructure and third-party video teleconferencing system (VTC) solutions such as Cisco/Tandberg VTC solutions. This is an independent server role cannot be collocated with any other server roles. This role is only required if you need to integrate third party video teleconferencing systems with Skype for Business Server.

Apart from all these roles, there is one more server role which is not part of the Skype for Business Server but it is required if you have to collaborate with external/federated/remote users. Reverse Proxy server is required to share web content such as meeting url etc. The existing reverse proxy server can be used if exist in the environment.