Windows 2000 Advanced Server is a variant of Windows 2000 Server operating system designed for medium-to-large businesses. It offers clustering infrastructure for high availability and scalability of applications and services, including main memory support of up to 8GB. It supports TCP/IP load balancing and enhanced two-node server clusters based on the Microsoft Cluster Server (MSCS) in Windows NT Server 4.0. Limited number of copies of an IA-64 version, called Windows 2000 Advanced Server, Limited Edition were made available via OEMs. System requirements are similar to those of Windows 2000 Server, however they may need to be higher to scale to larger infrastructure.