Windows Network Load Balancing (NLB) is an optional component of Windows Server. It load balances network traffic, sent to a cluster virtual IP address, among multiple servers in a cluster. It requires Microsoft Clustering to be used. Complex server deployments using the Windows Server NLB solution can sometimes exhibit poor performance if not configured correctly. A dedicated hardware based load balancing solution, that is separate from the core server infrastructure, provides a more robust and scalable solution.