SABSA Development Process
The SABSA Model provides the basis for an architecture development process, since it is clear that through understanding the business requirements, the architect can create the initial vision. This is used by the designers to create the detailed design, which in turn is used by the builder to construct the systems, with components of various sorts provided by specialists. Finally, the facilities manager operates the finished system, but unless the earlier phases take account of the operational needs, this phase in the lifetime of the system will be fraught with difficulty. The development process itself is shown, at a high level, in the following diagram.
The SABSA Development Process
The high-level development process (see diagram above) indicates that there is a natural break after the first two phases. Once the Contextual Architecture and the Conceptual Architecture are agreed and signed off, then work on the later phases can begin, with considerable parallel working. However, it is difficult to make useful progress on the later stages until these first two are fairly fully defined. The temptation to go straight to an implementation of certain products and tools should be avoided, since this is the source of so many severe problems during the operational phase.
It is also important not to be confused by the positioning of the sub-process ‘Define Operational Security Architecture’. The Operational Security Architecture itself cuts across all of the other five layers, but the development process for that Operational Security Architecture is best delayed until after the Contextual and Conceptual Security Architectures have been defined and signed off.