Requirements Modelling and Specification for Service Oriented Architecture

6.3. The Mission Grid as a Roadmap for SOA

In the context of contemporary IT systems, the mission grid is about SOA in the large. Each cell in the grid contains descriptions of the services that a business needs in order to operate: sales, logistics, production, etc. The technique has forced us to decide which processes are differentiating or customer facing. We have been encouraged to assign priories based on this analysis and other factors, such as competitive opportunity or technical innovations. Moving to SOA is now best achieved by organizing it around building SOAs for the high priority process areas.

One of the killer mistakes that people make in implementing SOA is ignoring the need for a common language with shared semantics. Without such a language enterprise integration is doomed to fail. Process relationships and business rules in the mission grid can provide the basis for semantic translations, e.g. prospects from the Sales process become customers when an order is created in Order Processing.

The mission grid construction process starts with shared goals. If services are constructed to support these goals they will be more generic, more reusable and more focused on business agility. The mission grid rules show how process areas will be integrated as, area by area, SOA is introduced.

In summary, the mission grid technique:

• gives a top level view of all the processes that are candidates for migration to enterprise SOA;

• helps us prioritize and order the process of transition ...