A service topology is a pattern for composing a distributed application.

Different types of topologies will exist in computing environments. Typically, a physical network will have a topology as identified by the actual wires connecting the computing devices. The next level of abstraction, the logical network, an addressing scheme may utilize a point-to-point topology that abstracts the participants from the physical schema. Above all of this, the service topology is abstracts the participants from both the physical and logical network.

Thus, the service network may have a single or composite topology. This topology is abstracted from the lower layers. One can be on a hub & spoke physical network, where packets are directed along a point-to-point logical network and utilize a hub & spoke service-brokering mechanism (like WSO)

See: Hub & Spoke, Point-to-Point