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Server CAL requirements by product
Windows Server 2012 R2 and Windows Server 2012
Windows Server 2012 user and device CALs should be purchased separately for Windows Server 2012 and 2012 R2 products as shown in the table below. The Windows Server 2012 CALs may be used for prior Windows Server Versions. The CALs may be bought in packs of 1 and 5.
A server client access license (CAL) is a license that gives users and devices the legal right to access Microsoft server software installed on a server.
Server client access license (CAL) overview
When you sell a copy of Windows Server, the customer will receive a server license permitting installation of the operating system on one computer. A server license by itself does not provide the legal right for others to connect to that computer, whether they work for the company or not. Instead, each user needs a client access license (CAL).
Customers will need a CAL for each employee, or each employee device, that accesses the Windows Server installation, but not for anonymous users who access it over the Internet.
Server CALs are cost effective and affordable, allowing customers to pay only for the licensing they need with the option of buying more as their businesses grow.