Licenses for Skype for Business Server are based on physical or virtual servers in combination with Client Access Licenses (CALs) for the users.
A Skype for Business Server license is required for every Skype for Business Server. This applies to both physical and virtual servers. The license is assigned to a physical server. Skype for Business may then run on the licensed server or in a virtual server on that licensed server.
There is no distinction between Skype for Business Server Standard and Enterprise.
Only servers with a “Front-end role” need a license.
Licenses are assigned to physical servers and are associated with them for a minimum of 90 days. If a virtual Skype for Business server moves across multiple physical hosts, the license must be able to move with it. Microsoft calls this License Mobility and that right is included in Software Assurance (SA). Skype for Business virtual servers without SA must remain on the same host, unless all hosts that can land Skype for Business virtual servers have sufficient Skype for Business Server licenses.
Client Access Licenses (CALs)
Licenses are also required on the user side. These can be licenses per user or licenses per end user device (PC, laptop, Thin Client ...).
A per user CAL (user CAL) allows a user to use an unlimited number of devices to access an unlimited number of Skype for Business Servers. With a CAL per device (device CAL), an unlimited number of users can access an unlimited number of Skype for Business Servers via the licensed device.
For most uses, a Skype for Business Standard CAL is sufficient. The Skype for Business Enterprise CAL is available as an additional CAL and offers the following additional functionality:
- Audio, Video en Web Conferencing
- Desktop Sharing
- Room Systems
- Multiple HD Video Streams
There is also a Skype for Business Plus CAL, which offers this extra functionality:
- Voice Telephony
- Call Management
Skype for Business Standard and Enterprise CALs are part of the Core CAL Suite and the Enterprise CAL Suite. These suites are available on a per-user and per-device basis.
The Skype for Business Plus CAL is only available separately.
Microsoft Teams provides the same rights as the Skype for Business Standard and Enterprise CAL. The Plus CAL is included in Microsoft Teams Phone. These licenses are only available per user.
No CALs are required for external users. This applies to both the Standard and the Enterprise functionality.