Load balancing is an optimizing feature you use with clustered Integration Servers. Load balancing controls how requests are distributed to the servers in the cluster. A load balancer can be useful if you need load balancing for multiple types of servers, for example, web servers and application servers, in addition to Integration Servers. Load balancers also offer virtual IP support, but they are not "out of the box." Most load balancers perform load balancing in a round-robin manner or based on network level metrics such as TCP connections and network response time.

You can always use load balancing with stateful clusters. You can use load balancing with stateless clusters if you are not using any of the unsupported features or components listed in the table above..