Good morning Srinivas, If I understand your question,  under Windows 2008, Microsoft has removed the CAL restrictions and is now on the honor system.  You only have to have the licenses on file.     If you are asking about virtual clients, you have one physical key and one virtual key.  For additional virtual clients, you will purchase those keys.  Regards,
I had  dell power edge r 710  with Windows 2008 Server with CALs  pls let us know which key has to be used to install the clients. virtual key or physical key pls clarify.   regards srinivas
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