During the past weeks I had numerous conversations with different partners and customers around Microsoft Teams.
In most cases, the general opinion is that Microsoft Teams is perceived as a Skype for Business rebranding.
For this reason, I decided to write the present post to clarify what Microsoft Teams really is and what are the main differences between Microsoft Teams and Skype for Business.
Let’s start from the product design: Skype for Business server is an evolution of Lync 2013 which was a product purely designed for On-Premise implementation. When Office 365 was created, Microsoft decided to adapt this product to the cloud ecosystem, knowing that it wasn’t optimized to handle the number of users we can potentially have in cloud in the near future.
For this reason, Microsoft Teams has been created, and together with it a completely new Skype backend infrastructure for enterprise grade voice, video & meetings. Microsoft leveraged the experience gained with Skype Consumer where 300 million active users are using the service every month.
The new backend is composed by microservices which have different functionalities. The benefit of decomposing an application into different smaller services is that it improves modularity and makes the application easier to understand, develop and test.
A high-level overview of the architecture is represented in the following diagram.
Clients:
The clients for MacOS, Windows and Web App are based on Electron, which allows developers to build a cross platform application.
This allows the user to have a consistent experience and basic functionalities across all devices.
Calling features are provided by an additional component running on the thick client whereas the browser version will user WebRTC in the future.
Microsoft Teams client doesn’t support the SIP protocol anymore, but rather uses HTTPS requests towards different services, as you can see at the bottom of the above diagram.
To establish Audio and Video sessions the protocol used by Microsoft Teams is ICE; the same protocol is used by Skype for Business (see the Transport Relay article in order to understand hsow the client use the audio relay service).
Microsoft Teams Back-End:
The Microsoft Teams back-end is composed by different services, every service providing specific features/capabilities.
There are three main services: Team Service, Chat & Presence and Next Generation Calling.
The Teams Service is used every time the client wants to communicate with SharePoint, Exchange, OneDrive, etc. It receives the request from the client and invokes the specific service for each component.
The Chat & Presence Service allows the users to Chat and see the presence, received notification, etc.
Eventually, the Next Generation Calling services handles all the requests related to Calls and Meeting. This service is also responsible for the interoperability with Skype for Business.
Last but not less important, Microsoft Teams has integration with AAD in order to leverage Identity protection and Authentication.
In the following image you can see how Skype for Business and Microsoft Teams use different services and protocols in order to provide some of the basic functionalities to the user.
Hopefully this article managed to shed some more light into the differences between Skype for Business and Microsoft Teams.
Microsoft Teams is not only the new “Skype for Business client”, it is the core communications client for Office 365 customers.
The idea behind Microsoft Teams is to have one single software that increases the user productivity andfacilitates team collaboration.
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