This product can only be purchased with a Fujitsu server Windows Server powers many of the worlds' largest datacentres, enables small businesses around the world, & delivers value to organizations of all sizes in between. Building on this legacy, Windows Server 2012 redefines the category, delivering hundreds of new features & enhancements spanning virtualization, networking, storage, user experience, cloud computing, automation, & more. Simply put, Windows Server 2012 helps you transform your IT operations to reduce costs & deliver a whole new level of business value. A server Client Access License (CAL) is a license that gives users & devices the legal right to access a server installed with Microsoft server software. 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, but not for anonymous users who access it over the Internet.