Remote Desktop Licensing (Terminal Services Licensing) is one of those things that is not well understood, and there hasn’t been a lot of quality documentation on it…until recently. The Directory Services team at Microsoft has written a good article that should answer all the questions you’ll ever have on Remote Desktop Licensing, such as: 

• The different types of CALs and how they work
• License Server Discovery and how it works
• How the Grace Period really works
• Installing or Migrating CALs
• Lots more useful stuff

The article can be found here.

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