Definitions for "Client Access License"
Keywords:  sharepoint, cal, portal, license, mspx
A license required for devices accessing certain Microsoft server products.
a software licensing approach used by some vendors, and provides authorization to access a software product
CALs are required for each desktop or user that is accessing a Windows Server, Windows Terminal Services, Exchange, SQL, SMS, SharePoint Portal Server, Office Live Comm Server, and Project Server. Per Processor licenses are available for many of the above products as an alternative licensing method. When do you need a CAL? Microsoft has good discussion of this topic at: Look for "Server Customer Guide" You might also download the "Product Use Rights" which are the final word on license terms under the volume licensing programs.