Main Phases of Development Processes for Large Scale Software Systems (1)

The development process for a large scale system being developed using a RUP method comprises of mainly six parts. These include:

1) Requirements

2) Specification

3) Provisioning & Assembly

4) Testing

5) Deployment

This process is usually aimed at developing systems at a large scale which are usually characterized by increase in complexity, increase in overhead due to management of a larger pool of resources[1], sheer scale of the system, and virtualization. As listed before, the process and models produced at each phase include:

1) Requirements At this phase, the requirements for the system are captured and defined. These requirements can be split into Social Context requirements and Technology requirements.

Social Context requirements are the factors taken into account such as the Enterprises’ objectives, product innovation, the model of the Enterprises business process, legal rules, stakeholders etc.

Technology requirements on the other hand deals with user-friendliness, ease of use and other non-functional requirements, integration issues with any current software etc [2]. Both requirement types are important for the system in order to enable development of the system to be a success.

From the Business processes, three requirement models can be deduced. These include: a) Business, b) System, and c) Domain models which each of them are depicted using Use-Case diagrams. Together the three models can be referred to as the Requirement Model as shown in figure below [3]:

A Business Concept Model is developed. This model simply describes the business concepts and relationships between these concepts, business rules usually obtained from business documents such as memos, reports and anything relevant to the project.

Domain models are more detailed than the Business Concept models though there are no clear-cut boundaries as to where the Business Concept model stops and where the Domain model starts. They are as a result of dividing the Business model so as to apply Object Oriented principles and take architectural guidelines into consideration [3].

System models which are a specialization of the Domain model [3], are obtained by infusing an architectural feedback. The System model and the Domain model are not completely distinct unlike the Business model.

Also use-case models which are used to identify any operations and interfaces are developed at this phase. This model gives a view of the requirements for the system to be developed and also help in showing how the software will meet its responsibilities. It is also used to identify system interfaces and operations This model is produced at the initial stage as its modelling process stops at the Assembly phase.

It is particularly important that there must be a relationship between the Business and Domain requirement models in order to manage changes to requirements.

References

[1] Developing Large-scale Systems with the Rational Unified Process By Maria Ericsson. Rational Software White Paper. Rational

[2] Chris Simons. Component Based Software. Lecture 2 — Requirements Capture & Testing For Large Scale Software Systems. CEMS, UWE. Bristol

[3] JOURNAL OF OBJECT TECHNOLOGY. Online at https://www.jot.fm. Published by ETH Zurich, Chair of Software Engineering ?JOT, 2008 Vol. 7, №8, November-December 2008. Requirements analysis for large scale systems Roger Johnson, George Roussos,and Lucas Vetti Tagliati. https://www.jot.fm/issues/issue_2008_11/article3.pdf