164 ◾ Information Security Management Handbook
Web Services and SOA: An Alternative Service Bus
Unlike an internal SOA, a Web Services-based SOA cannot rely upon a single monolithic ser-
vice bus. To this end, Web Services are based on slightly different principles than a traditional
SOA. Each service needs to be reusable, stateless, autonomous, abstract, discoverable, and loosely
coupled. Instead of a form of service bus, you have a service integration layer, which operates as a
logical or a virtual service bus.
e services engage with this service integration layer and with each other through a for-
mal contract that defines the terms of information exchanged and provides supplemental service
description. Since services need to be discoverable, ...