Windows Server 2003 (sometimes referred to as Win2K3) is a server operating system produced by Microsoft, released on April 24, 2003. An updated version, Windows Server 2003 R2, was released to manufacturing on December 6, 2005. Its successor, Windows Server 2008, was released on February 4, 2008. It is based on Windows XP, basically becoming an enhanced version of XP. According to Microsoft, Windows Server 2003 is more scalable and delivers better performance than its predecessor, Windows 2000.
Windows Server 2003 Enterprise is aimed towards medium to large businesses. It is a full-function server operating system that supports up to 8 physical processors and provides enterprise-class features such as eight-node clustering using Microsoft Cluster Server (MSCS) software and support for up to 64 GB of RAM through PAE (added with the /PAE boot string). Enterprise Edition also comes in specialized versions for the x64 and Itanium architectures. With Service Pack 2 installed, the x64 and Itanium versions are capable of addressing up to 1 TB and 2 TB of RAM, respectively. This edition also supports Non-Uniform Memory Access (NUMA). It also provides the ability to hot-add supported hardware. Windows Server 2003 Enterprise is also the required edition to issue custom certificate templates.