SOA project lifecycle

This topic provides a more comprehensive overview of the service-oriented architecture (SOA) project lifecycle and the artifacts and skills required at each stage.

Figure 1. Guide and early phases of the software lifecycle

Although the approach defined is top-down, the top-down approach may not always be appropriate.

Organizations nowadays investment heavily in existing systems, and service-based solution ultimately rely on those systems for their runtime operations. For this reason, the latter topics of this document discuss the compromises in connection with the top-down methodology described here to ease the task of connecting ideal-world service definitions to existing systems.

Note: understand the methods and principles that underpin a top-down approach before modifying this approach to meet project needs.

The software lifecycle runs from inception of a software project to software implementation and testing. In this lifecycle, IBM Industry Models play a role in all phases up to design.

Note: IBM Industry Models do not play an essential role in:

Final phases of design
SOA implementation and testing

Software lifecycle phases:

Produce distinct outputs in the form of model artifacts
Include methods and principles that govern the creation of those outputs

Figure 2. Outputs of the customization guide

This figure outlines the outputs as they relate to the specific problem of service design. This is not the only task within a project initiative. The derived services only support a subset of the total project requirements. Process analysis also yields details of manual procedures and front-end or channel applications that interact with the identified services to form a complete solution to a business need.

These topics focus on the use of IBM Process and Service Models to identify, analyze and define reusable services, while maintaining a clear picture of how these services relate to business processes. These business processes govern:

Human tasks
Interaction of tasks with front-end applications
Delegations by applications to a services-based infrastructure

Each part of a business process can yield different requirement types. Requirements that indicate the presence of manual procedures can result in the definition of procedure documents guiding employees behavior. Tasks that indicate a requirement for front-end or channel applications often yield detailed Unified Modeling Language (UML) models, describing the operations of applications. The identification and analysis of reusable business services results in service analysis within the Business Object Model (BOM), followed by service design within the Interface Design Model (IDM). Analysis of the overall business process governs how the individual elements come together to satisfy the business requirements.

Strategy, project scoping and value chains
This topic discusses strategy, project scoping and value chains.
Process analysis
Process Analysis is used to identify and define the tasks and activities that take place during each phase of a business process. It is also used to describe the data inputs and outputs for each activity. Process Analysis using the APM Processes can help to understand how the process operates and to identify potential improvements in existing processes.
Service analysis
The objective of the Service Analysis Roadmap step is to use the Business Object Model (BOM) to define an enterprise view of the business concepts and capabilities that relate to the documented requirements, independent of implementation considerations.
Service design
The objective of the Service Design development phase is to use the Interface Design Model (IDM) and one of the platform-specific SOAP Service Design models (Web Services Design Model (WSDM)/Java Services Design Model (JSDM)/or Message Service Design Model (MSDM), or the RESTful API Design Model, for REST Services, to define an enterprise view of the business concepts and services that express a design for the documented requirements, independent of implementation considerations.
Process design
The process design step of the Industry Models Customization Roadmap involves the design of executable processes based on the given business requirements. Design-level processes are composed by the Orchestration Process Model (OPM) in the Process and Service Models.

Parent topic: Structured and model-driven development