The Unity Licensing Server uses a floating license model.

The Unity Floating Licensing system has two components:

The Unity Licensing Server is an HTTP or HTTPS server built on the ASP.NET framework. It manages a pool of Unity Editor licenses. Computers that have the Unity Licensing Client installed connect to this server to request licenses.

When a user starts the Unity Editor on their computer, the client connects to the server to request the license. If there are enough licenses in the pool, the server removes a license from the pool and assigns it to the client, until the client computer releases it. When the user closes the Unity Editor, the client releases the license back to the pool. If the client computer doesn't renew the license after a specified amount of time, the server releases the license back to the pool automatically.

Any client computer configured to connect to the server can request a license as long as there are still licenses left in the pool.

Starting with version 2.0 of the Unity Licensing Server, users can check out a license to work offline. This feature provides users with a valid Unity Editor license, even when they don't have a network connection to process a license request. For more information, refer to License checkout to work offline.