Network Load Balancing
Network Load Balancing (NLB) allows you to load balance network traffic (sent to a cluster virtual IP address) among multiple servers in an NLB cluster.
To use NLB, install NLB on a server and add two or more machines to the NLB cluster. Each machine uses two IP addresses: a unique address and the cluster address. This allows the DNS server to respond to clients by sending them to a single IP address. Each server in the cluster runs an algorithm to determine which server responds to the next request. You can have up to 32 machines in an NLB cluster.
NLB is a dynamic method for load balancing in that if a server fails (or if a server is added to the cluster), NLB recognizes the change and compensates for it through convergence, a process whereby the server is removed from (or added to) the cluster.