Dealing with Windows Terminal Services licensing issues

Terminal Services complex licensing requirements -- specifically TS Licensing role service -- can be intimidating. Learn how to choose the most cost-effective licensing scheme.

Microsoft Corp. is notorious for having complicated license requirements for many of its products. But this isn't...

necessarily a bad thing.

A couple of years ago, I asked Microsoft CEO Steve Ballmer why the company tends to overcomplicate software licensing. He explained that licensing requirements are designed to give organizations multiple options for licensing software and thus allow an organization to choose the most cost-effective licensing scheme.

There are multiple license requirements for Windows Terminal Services (TS). These requirements vary depending on how TS is used and what version of Windows it is being used on (This article deals with Windows Server 2008).

Available license types
Five types of licenses are available for Terminal Services in Windows Server 2008:

License Function
Windows Server License Every Windows 2008 server requires a Windows Server License. This license allows TS to be used.
Windows Server Client Access License Any computer connecting to a Windows server requires a Client Access License (CAL). Although the basic CAL does not cover TS use, it is still required for general connectivity to the Terminal Server.
TS Device CAL In addition to the CAL, computers connecting to TS require an incremental CAL that is specific to Terminal Services. One option is to use a TS Device CAL. This CAL licenses any device to connect to Terminal Services, regardless of how many users actually use that device.
TS User CAL An alternative to the TS Device CAL is the TS User CAL. This CAL allows one user to connect to Terminal Services from any device.
TS External Connector The TS External Connector license allows external users to connect to Terminal Services. This is a server-level license, and you will have to license each Terminal Server if you provide external connectivity.
Service Provider License The Service Provider License is intended for service providers that offer hosted services to their customers.

Typically, the most cost-effective way to license TS is either TS User CALs or TS Device CALs. Alternatively, you can use a combination of TS User and TS Device CALs should the need arise.

TS Licensing Role Service
The actual license requirements for Terminal Services aren't that complicated, but many administrators are intimidated by the TS Licensing Role Service requirement. The TS Licensing Role Service isn't a license type, but rather a mechanism for enforcing Terminal Services licensing.

Before deploying TS Licensing Role Service, keep in mind that it must be hosted on a server running Windows Server 2008. Although similar functionality existed in Windows Server 2003, a Windows 2008 Terminal Server can't communicate with a Windows 2003 license server. But it is possible for a Windows 2003 Terminal Server to communicate with a Windows 2008 license server.

In previous versions of Windows, the licensing server could only track per-device licenses. In Windows Server 2008, the TS Licensing Role Service is also capable of tracking TS User CALs, provided that users are domain members. This requirement exists because the Active Directory database is used in user-level license tracking. Essentially, each user connecting to the Terminal Services must have a TS User CAL (unless they have a TS Device CAL). If a TS User CAL does not exist for the user, then a CAL is retrieved from the TS Licensing Role Service.

It is important to have the proper licenses for Terminal Services. Not only does TS Licensing Role Service enforce proper TS licensing, but there can also be civil and criminal penalties for incorrect licensing.

Brien M. Posey, MCSE, is a Microsoft Most Valuable Professional for his work with Exchange Server and has previously received Microsoft's MVP award for Windows Server and Internet Information Server (IIS). He has served as CIO for a nationwide chain of hospitals and was once responsible for the Department of Information Management at Fort Knox. As a freelance technical writer, Posey has written for Microsoft, TechTarget, CNET, ZDNet, MSD2D, Relevant Technologies and other technology companies. You can visit his personal website at www.brienposey.com.

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