4. REQUIREMENT phase

The requirement phase basically consists of three activities:

1. Requirement Analysis

2. Requirement Specification

3. Requirement Validation

Requirement Analysis

Requirement Analysis is a software engineering task that bridges the gap between system level software allocation and software design. It provides the system engineer to specify software function and performance indicate software’s interface with the other system elements and establish constraints that software must meet.

The basic aim of this stage is to obtain a clear picture of the needs and requirements of the end-user and also the organization. Analysis involves interaction between the clients and the analysis. Usually analysts research a problem from any questions asked and reading existing documents. The analysts have to uncover the real needs of the user even if they don’t know them clearly. During analysis it is essential that a complete and consistent set of specifications emerge for the system. Here it is essential to resolve the contradictions that could emerge from information got from various parties.

This is essential to ensure that the final specifications are consistent. It may be divided into 5 areas of effort.

1. Problem recognition

2. Evaluation and synthesis

3. Modeling

4. Specification

5. Review

Each Requirement analysis method has a unique point of view. However all analysis methods are related by a set of operational principles. They are:

1. The information domain of the problem must be represented and understood.

2. The functions that the software is to perform must be defined.

3. The behavior of the software as a consequence of external events must be defined.

4. The models that depict information function and behavior must be partitioned in a hierarchical or layered fashion.

5. The analysis process must move from essential information to implementation detail.

Requirement Specification

Software Requirements Specification plays an important role in creating quality software solutions. Specification is basically a representation process. Requirements are represented in a manner that ultimately leads to successful software implementation.

Requirements may be specified in a variety of ways. However there are some guidelines worth following: -

• Representation format and content should be relevant to the problem
• Information contained within the specification should be nested
• Diagrams and other notational forms should be restricted in number and consistent in use.
• Representations should be revisable.

Software Requirements Specifications:

The software requirements specification is produced at the culmination of the analysis task. The function and performance allocated to the software as a part of system engineering are refined by establishing a complete information description, a detailed functional and behavioral description, and indication of performance requirements and design constraints, appropriate validation criteria and other data pertinent to requirements.

An outline of the Software Requirements Specification:

A simplified outline can be given for the framework of the specifications. This is according to the IEEE Standards.