i just finished two days Microsoft Office365 Summit in Amsterdam, where i attended all IT-pro sessions about Skype For Business server 2015, yes Microsoft could’ve done better job with the naming.

Anyway it was really educational for me, and i decided to share the notes i took in the sessions which some could be repeated and mentioned in other articles for other bloggers that already attended the Office summit in other countries…but hay i want my readers and followers to have everything needed here in my blog.

Note: if you already don’t know you can download the presentations of the event from Office summit website (

Note also: i will be using Skype4b to refer to Skype For business server 2015 ….urgh see why i have to do that 🙂

article will contain notes from 5 sessions that i attended:

  1. Skype4B: Architecture and Design Consideration
  2. Skype4B: New Meeting and Video Investment
  3. Skype4B: Upgrading To Skype4B – Correct the name
  4. Skype4B: Server Core & Voice Improvement
  5. Skype4B: Ensuring Media Quality in the network (Nothing much here except for SDN)

Skype4B: Architecture & Design Consideration

  • although this goes without saying, focus on adoption of the technology, train the users get them engaged to get the best out of the Skype4b experience
  • lifecycle of Skype4B start with planning then deploying, run it and administrate it and “DOES NOT” end at adoption.


  • Skype4B still support Resource Forest / user forest as well as Resource Forest / Multiuser forest but the later one is not recommended by Microsoft.
  • Skype4B as a Resource forest need FIM and Directory Sync
  • when moving to Skype4B (n-2) role still applies, which mean it is possible to move to Skype4B from Lync 2010 and Lync 2013 but not from OCS 2007 R2.
  • moving to Skype4B while having co-existence Lync 2010/2013 is not Supported, doable but will produce unstable and buggy deployment.
  • in place upgrade is now possible (only from Lync 2013)
  • Side by side migration is still possible, although i don’t see why would you think of that?
  • SQL Always-on is now supported
  • an upgrade from SQL Mirroring to Always-on will be available in Future
  • Lync 2013 / 2010 clients would be able to connect to Skype4B frontends.
  • Patching and updating the servers been improved (is done faster now and easier)
  • Smart Setup option which check for available updates before start deploying Skype4B

Video Interoperability Server VIS

following notes are actually combined from two sessions to make it easier for the reader

  • Skype4B / Lync team tired approaching Cisco to make a solution for integrating Skype4B with legacy VTC but Cisco as always “too cool for school” and didn’t help so Microsoft introduced new server role “VIS” Video Interoperability Server.
  • VIS is not a transcoding solution
  • VIS is a software solution
  • VIS allows p2p with Cisco VTC
  • VIS will be included already in the licenses, no extra costs or hidden fees.
  • VIS is dedicated server can be a pool to do signaling between Skype4b and the VT
  • no drag and drop
  • No calling from Skype4b to VTC, only VTC to Skype4b
  • Skype4B connection to the VTC will be over SIP-Trunk
  • VIS terminate the connection at one system and then connect to the other system.
  • VIS pool can serve multi VTC, but VTC can be registered only to one VIS pool
  • Need VTC running TC7.0.0 or above, some releases need to be validated after the release of Skype4b RTM.

Skype4B: Servicing the Existing Deployment & Upgrading to Skype for Business

Microsoft introduced two upgrade paths

  1. Migrate User mode (no-downtime)
  2. Offline mode (downtime)
  • no in-place upgrade from Lync 2010 to Skype4B, will have to use Co-existence way to migrate.
  • in-place upgrade from Lync 2013 to Skype4B will most probably require Lync 2013 CU5
Migrate User Mode (no-downtime)
  • to upgrade to Skype4B without downtime, you will need two different pools (Pool-1 & Pool-2)
  • move users from Pool-1 to Pool-2, do the in-place upgrade on the servers in Pool-1, then move the users back to Pool-1.
  • test Pool-1 make sure you are happy with the results – no going back here 🙂
  • move users to Pool-1 again, upgrade pool-2.
  • when moving from Lync 2010 to Skype4B, build a new Skype4B infrastructure, carry on with the Co-existence scenario,as in test, move users, move CMS then decommission Legacy Lync 2010.
  • if you have Co-existence between Lync 2010 & Lync 2013, you should move to purely Lync 2013 then make in-place upgrade to Skype4B, as mentioned before you can do the movement to Skype4B while having Co-existence but it will produce problems and bugs and you cannot complain to Microsoft.
  • this will be needed like when migrating from single Standard edition pool for example.
  • you won’t have to migrate users to other pool.
Other Notes:
    • for in-place upgrade you need to be running SQL 2012 SP1, if not you ha
Offline Mode (Downtime)
  • ve to upgrade the SQL first (require downtime) then run the in-place upgrade which will upgrade it to SQL 2014.
  • SBA (like AudioCodes) won’t have in-place upgrade
  • Already existing integration with Exchange should not be affected.
  • enabling Topology in Skype4B need time so be patient with it even if it look like it is not responding
  • no need for Schema, Domain or forest extending – Not sure about that*
  • when talking about Edge server with Skype4B, role of (n-1) applies, meaning Lync Edge 2013 will support Skype4B
  • SQL Always on is supported in same subnet
  • SQL always on is aimed for High availability not for DR
  • in-place upgrade for SQL to Always-on is possible
  • Start-CsPool is new cmdlet which will check the Services , windows fabric and then start the frontend in the pool
  • Windows Fabric V2 is used with Skype4B which solved a lot of known issue with Lync 2013 (e.g. frontend services in Lync 2013 stuck in starting status)
  • Invoke-CsFailover is used when patching the servers, it take care of checking the health status of the servers as well as draining the services before stopping them.

Skype4B: Core Server & Voice Improvements

Core Server Improvements
  • Reduction of the Traffic for sign-in by 25% is achieved by allowing Lync client to cache most of the required information
  • Improved the Mobile experiences when switching between Wi-Fi and 3G
  • improve the forking when it comes to IM, to overcome the problem of lost IM
  • For mobile Multifactor authentication, ADAL (Azure AD Directory Auth Library) can provide that
  • same conversation history across different platforms (Mobile , Desktop), Skype4B save last 50 recent conversation
Conference Improvements
  • When failover inside same pool or between pools, Conferencing was disconnected, with Skype4b Conference State is now synced to the backend, and the conference status traffic is prioritized over other Skype4b Traffic
  • scheduled conference has now longer expiring date for better handling of expired dates.
Voice Improvements (download the PPT and check the voice part)
  • Call via work is the replacement of RCC
  • RCC is supported with Lync but not supported with Skype4B
  • In Skype4b, when calling via work, Skype4b will not call back to your phone, it will call back to your PBX phone (or the defined call back number by user or admin)
  • Call via work, will allow to call federated partner and Skype4C
  • Call via work is only an outbound call, not inbound
  • Only available on-primes, not available for Skype4B online.
  • Presence will now be updated when you in a call using the PBX phone
  • Response group were re-written and has improved scalability

Skype4B: New Meeting and Video Investments

  • Outlook add-on will always automatically fixes problem with meeting by checking them, and the expiration time for scheduled meetings is extended by 1 year.
  • Client Telemetry can be enabled to your entire infrastructure and you can report bugs and problems which is handled by Microsoft team for fixing
  • Client telemetry for Outlook add-in is release in October 2014 update
  • With Lync 2013 when failover , meetings might work, with Skype4b made sure that meetings continue
  • While uploading a presentation, no message will appear to other participants until the upload is done and ppt is approved.
  • The Microsoft Surface hub does not mean that LRS is no more, the LRS still going to be produced.
  • Surface Hub is different from LRS, different requirements, different user base.
  • Direct search on Skype directory using name and city
  • No share desktop, no ppt as of yet
  • Using Silk for audio and SVC for Video
  • Enhanced TLS connection between Skype4B and Skype4C
  • WebRTC coming soon with Skype4B
  • Azure media services using webRTC and no plug-in – coming soon allowing 1000+ participants in same meeting.
  • SKype4B will support large number of meetings – more than 250 users
  • Enterprise Voice will be available online in future but not with all functionality of PBX – first in the USA then world
  • In future Skype4B will support Dial-in access numbers – first in the USA then the world
  • You can hide attendees in Lync as well as Skype4B – i did not know that 🙂

Skype4B: Ensuring Media Quality in the Network

  • MOS Audio max value 4.72 so don’t expect anything more than that 😛
  • Skype4B will have the pop up message after conversation to rate the call
  • Use the CQM to monitor the quality in your network where it check the following:
    • Servers (hardware, software …etc.)
    • Network
    • End point
Skype4B & SDN
  • Application that can be installed on Lync serer “LDL” send the information to the SDN manager pool about the subnet which is forwarded then to the Controllers, which then decide what to do to make the network better.
  • Openflow is smart to know there is another possible path for media incase the used path is busy following best diagram describe that


  • Current SDN providers
    • Nectar
    • HP
    • Aruba
  • Cisco were also “Too cool for school” and decided to go with another way with SDN and use programming languages like Java instead of the open standard protocols.

so here you go, that was my notes from Microsoft Office 365 Summit in Amsterdam hope you found them useful and stay tuned for more news about Skype for Business.