In this chapter we saw how the architect realizes particular quality attribute requirements. These requirements are the means by which a system achieves business goals. Our interest here was in the tactics used by the architect to create a design using architectural patterns and strategies.
We provided a list of well-known tactics for achieving the six quality attributes elaborated in Chapter 4: availability, modifiability, performance, security, testability, and usability. For each we discussed the tactics that are available and widely practiced.
As we discussed, in relating tactics to patterns the architect's task has only just begun when the tactics are chosen. Any design uses multiple tactics, and understanding what attributes are achieved by them, what their side effects are, and the risks of not choosing other tactics is essential to architecture design.