Microsoft Cluster Server (MSCS) is computer program that allows server computers to work together as a computer cluster, to provide failover and increased availability of applications, or parallel calculating power in case of high-performance computing (HPC) clusters (as in supercomputing).Microsoft has three technologies for clustering: Microsoft Cluster Service (MSCS), Component Load Balancing (CLB) (part of Application Center 2000), and Network Load Balancing Services (NLB).