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Analysis

Systems development has two major components: Systems Analysis and Systems Design.

System Analysis is the process of gathering and interpreting facts, diagnosing problems and using the information to recommend improvements to the system. This job is done by the system analyst.

For this the systems analyst needs to do the requirement analysis. A requirement is a feature that must be included in a new system. It may include a way of capturing or processing data, producing information, controlling a business activity, or supporting management. The determination of requirements entails studying the existing system and collecting details about it to find out what these requirements are

Requirements Determination can be viewed it through three major activities they are:-

1.     Requirements Anticipation

2.     Requirements Investigation

3.     Requirements Specification

Requirement Anticipation

Requirements anticipation can be a mixed blessing. On the one hand, experience from previous studies can lead to investigation of areas that would otherwise go from previous studies can lead to investigation of areas that would otherwise go unnoticed by an experienced analyst. Having the background to know what to ask or which aspects to investigate can be a benefit to the organization.

On the other hand, if a bias is introduced or shortcuts are taken in conducting investigation, requirements anticipation becomes a problem.

Requirements Investigation

This activity is at the heart of system analysis. Using a variety of tools and skills, analysts study the current system and document its features for further analysis.

Requirements investigation relies on the fact-finding techniques and includes methods for documenting and describing system features.

Requirements Specification

The data produced during the fact-finding investigation are analyzed to determine requirements specifications, the description of features for a new system. This activity has three interrelated arts:-

a.     Analysis of Factual Data: The data collected during the fact-finding study and included in data flow and decision analysis documentation are examined to determine how well the system is performing and whether it will meet the organization’s demands.

b.     Identification of essential requirements: These state the features that must be included in a new system, ranging from operational details to performance criteria, is specified.

c.      Selection of Requirements Fulfillment Strategies: The methods that will be used to achieve the stated requirements are selected. These form the basis for systems design, which follows requirements specification.

All three activities are important and must be performed correctly. The requirements specification places a great deal of responsibility on the systems analyst, for the quality of the work performed.

Fact-Finding Techniques

The specific methods analysts use for collecting data about requirements are called fact-finding techniques. These include the interview, questionnaire, record inspections, on-sight review and observation. Analysts usually employ more than one of these techniques to help ensure an accurate and comprehensive investigation. The fact-finding techniques are briefly described below:

Interview

Analysts use interviews to collect information from individuals or from groups. The respondents are generally current users of the existing system or potential users of the proposed system.

The respondents and analysts converse during an interview – the respondents are not being interrogated. Interviews provide analysts with opportunities for gathering information from respondents who have been chosen for their knowledge of their system under study. This method is frequently the best source of qualitative information. Other fact finding methods are likely to be more useful for collecting quantitative data. This method can be especially helpful for gathering information from individuals who do not communicate effectively in writing or who may not have the time to complete questionnaires.

Interviews can be either structured or unstructured.

In the present context this technique has been used where the information is gathered by interviewing the respondents and asking them questions regarding the existing system and what changes they want in the new system.

Questionnaire

The questionnaire is a method of data collection which can be used by the analyst in situations where it is impossible to interview all desired respondents because either the physical distances or the number of desired respondents are too large.

In this context questionnaire can be used to collect data from customers and suppliers. Questionnaires can be conveyed to respondents by mail, telephone or in person. These questionnaires can be constructed in two ways- Open-ended questionnaires and Closed questionnaires.

Record Review

In record reviews, analysts examine information that has been recorded about the system and users. In the present context also this technique is used to collect information as this involves various records like annual reports, business plans and forecasts, company handbooks and manuals, etc.

Observation

In this fact-finding technique the analysts observe and study the user in their workplace. This helps to understand how each employee works and interact with the current system. In the present scenario when this technique is applied it can be observed that the employees are doing paper work most of the time.

SOFTWARE REQUIREMENTS SPECIFICATION

Once the analysis is complete, the requirements must be written or specified. The final output is the software requirements specification document (SRS). A good SRS is: Understandable, Unambiguous, Complete, Verifiable, Consistent, Modifiable, and Traceable.

The SRS should specify the following basic issues: Functionality, Performance, Design constraints imposed on an implementation, External interfaces.

The basic structure of the SRS is as under:

1.     Introduction: - This includes Purpose, Scope, Definitions, Acronyms, and Abbreviations, References, Overview.

2.     General Description: - This includes Product Perspective, Product Functions, User Characteristics, General Constraints, Assumptions and Dependencies.

3.     Functional Requirements: - This includes Functional Requirements 1, 2, 3, so on. And each functional requirement consists of Introduction, Inputs, Processing, and Outputs.

4.     External Interface Requirements: - This includes User Interfaces, Hardware Interfaces, and Software Interfaces.

5.     Performance Requirements

6.     Design Constraints: - This includes Standards Compliance, and Hardware Limitations.

7.     Other Requirements

Design

Systems Design is the process of planning a new business system or one to replace or complement an existing system. The objective of the software design phase is to transform the SRS into design that is implementable using some programming language i.e. plan a solution for the requirements into a ‘blue print’ for construction. The design determines the success of the system. System Design is abridge between the requirements specifications and the final solution. Systems design goes through two phases of development:         

1.     Logical Design

DFD shows the logical flow of a system and defines the boundaries of the system. It describes the inputs (source), outputs (destination), data basis (data stores), and procedures (data flows), all in a form that meets the user’s requirements. In the present scenario this has been designed to determine the information flow into the system and the required resources. The design covers the following:

a.     Reviews the current physical system, its data flows, file contents, volumes, frequencies, etc.

b.     Prepares output specifications that is, it determines the format, content, and frequency of reports, including terminal specifications and locations.

c.      Prepares input specifications – it determines format, content and most of the input functions. This includes determining the flow of the document from the input data source to the actual input location.

d.     Prepares credit security, and control specifications. This includes specifying the rules for edit correction backup, procedures, and the controls that ensure processing and file integrity.

e.      Specifies the implementation plan.

f.       Prepares the logical design walkthrough of the information flow, output, input, controls, and implementation plan.

g.     Reviews benefits, costs, target dates, and system constraints.

2.     Physical Design

Following the logical design is the physical design. It produces the working system by defining design specifications that specifies what the system must do. In the design stage, the programming language and the platform in which the new system will run are also decided. Specifically, physical system design consists of the following steps:

a.     Design the physical system.

                                                                               i.            Specify input/output media.

                                                                             ii.            Design the data base and specify back up procedures.

                                                                          iii.            Design Physical information flow through the system and a physical design walkthrough.

b.     Plan system implementation.

                                                                               i.            Prepare a conversion schedule and a target date.

                                                                             ii.            Determine training procedure, courses, and timetable.

c.      Devise a test and implementations plan and specify any new hardware/software.

d.     Update benefits, costs, conversion date, and system constraints (legal, financial, hardware, etc.).