Orchestration is always related to task-orchestrated services and non-agnostic workflows that are devised for covering a single (but complex) business operation, which we discussed in Chapter 1, SOA Ecosystem – Interconnected Principles, Patterns, and Frameworks. This master service is a chain of service invocations and simple request-responses and/or complex transactions that involve several services at a time (ACID- or BASE-style). As mentioned earlier, this master service fulfills the runtime role called Composition Controller, which controls the service's composition members or other subcontrollers. This is a pure runtime role, and the next time you decide to include this master-controller into a more complex composition, the new role will be different (becomes a subcontroller). We also know that Composition Controller does not always start the service interaction (or service activities) within the composition. More often than not, a composition...