The SQL Server 2016 User CAL is a licensing model that allows you to pay only for users or devices that access the SQL Server 2016 database server.
A User CAL license gives a user the right to access SQL Server 2016 from any device. A User CAL license is required when a user accesses SQL Server 2016 from multiple devices, such as a PC, laptop or mobile phone.
To use the SQL Server 2016 User CAL license you also need a SQL Server 2016 server license!
The server license allows you to install and run SQL Server 2016 on a server. The server license does not limit the number or size of databases you can install. The SQL Server 2016 User CAL license gives you the flexibility and cost-effectiveness to manage your data with SQL Server 2016.