Migration of a Chosen Architectural Pattern to Service Oriented ...

Chapter 5. Guidelines 138namely vendor implementation, played more significant role than it was expected.This fact underlines a role of vendor selection and in the same time it questionsvendor diversity as SOA advantage. Additionally, application of some guidelinesdid not bring any result because there was no related code ( see figure 5.21 forthe result architecture ).5.5 DiscussionApplication of guidelines migrates systems that base on MVC architectural patternto Service Oriented Architecture. This section presents the target architectureand the guidelines in context of previously presented information.5.5.1 ProcessesAccording to section 4.3.2, creation of SOA is a result of sequence of followingactivities: Service Identification, Service Categorisation, Service Specification,Service Orchestration and Service Realisation. The guidelines presented in thissection match this process with small modifications. The modifications are causedby the fact that the original process is meant to elaborate system based on SOAfrom scratch while the guidelines migrate an existing system to SOA. The processof migration can be described as following activities:1. Context Establishment(a) Service Layers(b) Schema Centralisation(c) Policy Centralisation2. Service Categorisation + Service Identification(a) Entity Abstraction(b) Rules Centralisation(c) Canonical Resources(d) Utility Abstraction(e) Inventory Endpoint3. Service Orchestration(a) Process Abstraction(b) State Repository4. Frontend Migration