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Overview

Business domain experts participate in the development of any larger software system. This role has special knowledge and experience in the business domain (e.g., automobile, banking, etc.) of the system being developed. However, domain experts usually have no or only a limited technical background. They mainly participate in the development process during feasibility studies and requirements analyses and help in specifying the functionality and business logic of the system. Therefore, they have to interact closely with the system architects, who have a technical background and are able to tailor their requirements to a component-based software architecture.

For early QoS analyses, domain experts assist system architects in specifying the user interaction with the system. As they are familiar with the business domain and the targeted end-users, they should best be able to specify the anticipated usage scenarios and workloads of the system. The usage specifications may be based on experiences with similar legacy systems or on market analyses of the business domain. In the PCM, the usage specification consists of usage models (see Section 3.5.2), which are similar to UML use cases with attached UML activities. They additionally contain stochastical information (e.g., probabilities of choosing a branch in an alternative) and the notion of workload to characterise the number of users in the system, which is especially relevant for performance predictions. Usage models may be refined with a parameter model (explained in Section 3.5.3) to characterise the data values passed to component services by users.


next up previous contents index
Next: Usage Model Up: Domain Expert Previous: Domain Expert   Contents   Index
Snowball 2007-03-16