Related terms
One PRPC system can be supported by more than one node, forming a cluster. The term horizontal cluster means that multiple application servers are deployed on separate physical servers.
For example, a three-node PRPC system can consist of three instances of IBM's WebSphere application server, running on three separate servers. These form a horizontal cluster, providing throughput and high availability.
Horizontal clustering can be used in combination with vertical clustering, which involves multiple PRPC installations on one hardware server.