Client Access License. A license granting access to certain Microsoft server software.• User CAL A Core User CAL allows a unique user to access Microsoft server software from many devices, such as a work computer, a home computer, a laptop, an Internet kiosk, or a personal digital assistant (PDA), without having to acquire CALs for each device.• Device CAL A Core Device CAL allows users to access Microsoft server software through a single device.• Core CAL A license that allows customers to access Microsoft Windows Server, Microsoft Exchange Server, Microsoft SharePoint Portal Server, and Microsoft Systems Management Server through a single device.• User Core CAL A Core User CAL allows a unique user to access Microsoft server software from many devices, such as a work computer, a home computer, a laptop, an Internet kiosk, or a PDA, without having to acquire CALs for each device.• Device Core CAL A Core CAL based on the number of qualified desktops that access licensed server software. For example, a Core Device CAL allows users to access Microsoft server software through a single device.
The companion to a server license, a CAL must be acquired for every authenticated user on a network. The CAL allows a client application that runs on a personal computer or workstation to access a server and its program(s) to perform operations on the local computer.