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    Prof. DG JHA

    System Development Process

    Systems development refers to the process of examining a business situation with the

    aim of improving it through stream-lined procedures and methods. Systems

    development process can be broadly thought of as combination of two components

    Systems Analysis and Systems Design.

    Systems Design is the process of planning a new business system or one to replace or

    complement an existing system.

    Systems Analysis is the process of gathering and interpreting facts, diagnosing

    problems, and using the information to recommend improvements to the system.

    This is the job of Systems Analysts. The major responsibilities of a Systems Analysts

    are

    Defining requirements for improving or replacing the existing information

    system Ensuring cost-effectiveness of recommendations

    Guiding systems development and implementation activities

    Designing system flow and procedures to ensure control and security of data

    Testing system segments to ensure adequacy in meeting requirements.

    Systems Development Life Cycle (SDLC) Methodology:

    System Development Life Cycle (SDLC) methodology is a traditional

    development methodology that consists of a set of development activities that

    have a prescribed order.

    Once a problem or an opportunity for a new system is recognized, a request

    for development of the system is forwarded to planners. If approved and

    scheduled for development, a study is conducted to ensure that the proposed

    information system is feasible. The specification of the system requirements

    follows. Then come the System design, implementation, testing, conversion

    and evaluation. After the system evaluation, a recycling of development of

    activities may occur if problems that call for system modifications and/or

    redevelopment get identified. The term development cycle is used to

    acknowledge the importance of recycling in meeting the information needs.

    SDLC is the standard methodology followed at the time of development of

    information systems. One reason for which it is still favored is that a SDLC

    provides for project control and has logical order, with the output of each stage

    serving as an input for the next.

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    SDLC STAGE 1: Initiating A Development Request

    Once the need for an information system is identified within an organization

    a request for development of the system is forwarded to the person/s in the

    organization responsible for planning. A manager of a functional department,

    operational personnel, customers, unions or computer specialists may initiate

    a development request it sometimes gets originated through a suggestionbox too.

    Most companies have a planning officer or special section often called MIS committee

    that evaluates the requests for new system, to approve decisions and to establish

    development priorities.

    SDLC STAGE 2: Planning

    Planners while deciding upon long and short range planning objectives take into

    consideration: -

    Corporate goals

    Available resources

    Organizational constraints

    Technological trends

    Competitive environment

    SDLC STAGE 3: Feasibility Study

    A feasibility study determines whether a computerized information system can be

    implemented to generate the desired output, given the organizational constraints.

    Also, alternative solutions to the information problem are examined and ranked

    during the study.

    In addition, the cost of the proposed information system, in terms of both monetary

    and benefits is estimated. Proposed problem solutions are tested against the

    following constraints: -

    1. Economic feasibility

    Economic feasibility is conceptually simple if the expected benefits of a

    proposed solution are equal to or exceed the expected cost, the solution can be

    judged as economically feasible.

    In practice however, both sides of this equation are difficult to calculate during a

    feasibility study. The reasons could be

    User requirements are not fully formulated at this stage

    Preliminary cost estimates are often unreliable It is therefore perceived that

    the benefits of the solution are higher than the cost. Its savings that often

    matters the most while determining the feasibility of a particular solution.

    The implementation of an information system could very well result in cost

    reduction. It could be

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    Reduction of operation cost or clerical personnel

    Absorption of routine administrative functions thereby increasing the

    efficiency

    A cost-benefit analysis is also done to determine the economic feasibility.

    The primary objective of the cost-benefit analysis is to find whether it iseconomically worthwhile to invest in the project i.e., if the return on

    investment is good, then the project is considered economically worthwhile.

    Cost-benefit analysis is performed by listing down all the cost associated

    with the project. Cost can be classified into direct and indirect costs.

    Direct costs are those incurred in

    Buying equipment

    Employing people

    Rent etc.

    Indirect costs are those involving Problem time spent by user in discussing problems

    Gathering data about the problem etc.

    The benefits can be classified into

    Tangible Benefits Intangible Benefits

    Direct savings made due to reducing-

    inventories, delays in collecting

    outstanding payments, cost of

    production etc.

    Better service to customers.

    Savings due to reduction in manpower

    or increasing volume of work with thesame manpower.

    Superior quality of products etc.

    The sum of all cost is compared with sum of all savings. But it is not always easy

    to ascertain intangible benefits.

    2. Financial feasibility

    Often a proposed system may sound economically feasible, but the firm may lack

    sufficient capital to support implementation of the system. It is important that the

    study team determine the financial feasibility at this stage i.e., the availability of

    funds to finance systems developments.

    Study teams often consider the economic and financial constraints together and

    issue a single decision on economic and financial feasibility.

    Financial feasibility is based on information provided by personnels in the finance

    section of the organization, who decide on Whether the money is to be borrowed,

    or whether internal financing will suffice, or whether the combining of both is

    required. Capital budgeting decisions in large firms generally require complex

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    calculations to determine relative merits of project competing for funds. In such cases,

    it becomes difficult for the management to decide between allocation of limited

    financial resources to research and development, to plant renovation, to staff

    expansion, to the development of new information system or to other projects and at

    the same time achieve the target rate of investment.

    3. Organizational feasibility

    Proposed solutions must also be tested against organizational constraints

    Does the company have the adequate staff to implement the new system?

    Will the employees support the system or resist it?

    If any organizational constraint exist then the employees may have to

    Alter their work patterns

    Accept some experimentation

    Work in an atmosphere of change

    Acquire administrative and technical skills to implement the system

    The most important factor in testing the organizational feasibility is the attitude of

    the management towards the proposed system. If the management believes that the

    system will not contribute to business objectives and is a waste of corporate

    resources, they will not give the system the support needed to make it a success.

    4. Technological feasibility

    Sometimes the solutions may not be feasible due to technological constraints. For

    Example, an information system that requires reliable, inexpensive equipment to

    read handwriting is not feasible at times because devices meeting this requirement

    may not be available in the market.

    The technological considerations take into the account whether the necessary

    hardware, software and application tools are available for the desired solution

    under study.

    Often there may be risk or probability factor involved, the

    elements/equipments/devices may be future items promised but yet not available.

    It therefore becomes essential for the management to check

    The reliability of the vendor claims

    Whether the particular item is on the critical path

    Insurance in case of late delivery

    Each of the items required must be carefully evaluated to ascertain its relevance in

    information system development. Higher the dependence on sophisticated

    technological items; the greater is the risk factor in selecting a particular application

    for development. It is up to the committee to determine whether the technological

    limitations such as these exist for the problem at hand.

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    5. Operational feasibility

    Quite often, operational feasibility is most overlooked element in the entire

    feasibility analysis. Operational feasibility is whether the proposed solution can fit

    in with existing operations. A particular solution may look technically and

    economically feasible but may fail to produce the forecasted benefits because of the

    fact that the company is unable to make it functional.

    It is necessary to assess management, non-management and general operational

    considerations. The major focus of the application must be ascertained and

    resulting impact on the top, middle and operational management must be analyzed.

    6. Other feasibility consideration

    While doing feasibility analyses it is important to consider the internal as well as

    external constraints. The information system will have little or no value unless they

    are completed as per the schedule.

    The results of the feasibility study are forwarded to the corporate managementalong with the recommendation to continue or discontinue the project. The final

    decision whether to proceed to next phase or not rests with the corporate

    management.

    If the management agrees with committees recommendations and decides to

    proceed with the system development. The following steps are initialized

    A budget for the project is authorized

    A development schedule for the project is prepared

    The long run operational plans and development schedules are updated

    Development policies and procedures are framed

    Development personnel are selected, including the project leader.

    SDLC STAGE 4: Specifying System/User Requirements

    This phase concentrates on defining the system objectives and formulating the

    specifications for the information system under development. A system

    requirements statement is prepared that outlines

    Reports to be generated

    Processes to be performed

    Inputs needed

    Resources required

    Procedures to be followed

    This acts as a framework for the design of the new system

    Corporate management may decide to terminate the project after reviewing the

    system requirement document. Some of the reasons why the project may be shelved

    at this stage could be-

    Management dissatisfaction with the specifications

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    Estimated costs going higher

    Unavailability of expected resources

    Revised corporate priorities

    SDLC STAGE 5: System Design

    During the system design, the analysts draw up entire operational plan. The model(mathematical representation) and algorithm (step-by-step process) to be used in the

    problem solution is selected. The database is designed. Hardware costs, capability,

    speed, error rates and other performance characteristics are specified. Changes to

    be made up in the organizational structure are outlined. Input/Output files, forms

    and procedures are planned. Finally, standards for listing, documentation and

    system control are formulated.

    SYSTEM ANALYSIS v/s SYSTEM DESIGN

    When a computerized information system is under development, analysis activities

    are called systems analysis. The environment in which the system will operate is

    studied, the problems are identified, and the tasks that need to accomplished aredetermined. The specification of users need is the objective of this study.

    What is done during the system analysis?

    Obtain functional specification based on revised user requirement and feasibility

    analysis.

    End product of system analysis phase

    Functional specification

    Budget schedule

    Physical requirement such as storage and processor

    The design phase, called system design consists of planning the use of information

    technology to meet users specifications.

    What is done during the system design?

    Logical design of programs

    Design of database

    Test and implementation plan

    End product of system analysis phase

    Logical design of database, programs and test plans

    SDLC STAGE 6: System Implementation

    The most important part in the implementation of a computerized information

    system isprogramming.

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    The implementation activity also include

    Database organization i.e., creating new files or restructuring the old. The

    collection, verification and storage of additional data may also be required if

    the needed data doesnt already exist in the corporate database.

    Systems orientation and training: it becomes essential for the operating

    personnels to get tuned with the development process as they are the peoplewho are expected to use this system when it goes online.

    Preparation of manuals and documentation of procedures.

    SDLC STAGE 7: Testing The Solution

    Once the programs are written, procedure developed, organizational changes

    implemented, data collected and hardware installed, the new system gets ready for

    testing. Testingand debuggingare vital steps in developing computer programs. In

    general, testing is the process of making sure the program performs as intended;

    debugging is the process of locating and eliminating errors.

    During testing the actual performance of the system is compared with the desiredsystem performance. The common testing methods include pilot testing, parallel run

    and simulation techniques.

    The sequence in which the testing activities normally occur is

    Unit Testing

    (Testing of Individual programs)

    Volume Testing

    (Testing the application for large

    amount of data)

    Acceptance Testing

    (Conducting any tests required by

    the user)

    Unit Testing and Acceptance Testing The main purpose of testing an information system is to find errors and correct

    them. A successful test is one that finds an error.

    Once the modules are developed, the unit testing is carried out to confirm data

    transaction and outputs validity and accuracy. In this testing, transaction level

    processes are checked to confirm the input-process-output relation, and the data

    storage and the transaction level updating.

    System Testing

    (Testing the entire system ofprograms)

    Integration Testing

    (Testing all related sub-systems

    together)

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    When the unit testing is over and module level processes are confirmed, the modules

    are put together to generate the information as determined in the requirement

    definition. The process of putting the modules together is a process of integration. It

    is intended to produce the results of data integration.

    The system so developed is tested as a whole for several aspects such as information

    quality, performance, utility, user acceptance and so on.

    Once the system testing is complete, the system is implemented at site, on the

    hardware and software platform. The system implementation step has its own

    procedure starting from installation of hardware and software, training the users,

    and then shifting to fully designed system.

    While implementing the system minor modification and/or adjustment may be

    required for ease of acceptance by the user. The system is designed keeping this

    natural requirement in post implementation stage. A good system design and itsimplementation has higher user acceptance because it helps solve the problem in

    business performance, and meets the information need, within a stipulated time

    frame, with an assured quality and security of information.

    System Testing

    System-level testing is one of the most essential components before installation of an

    information system. It involves-

    a) Preparation of realistic test data in accordance with the system test plan,

    b) Processing the test data using new equipment,

    c) Thorough checking of the results of all system tests, andd) Reviewing the results with future users, operators and support personnel.

    System-level testing is an excellent time for training employees involved in the

    operation and maintenance of Information System.

    Alpha and Beta Testing

    If software is developed as a product for many customers, it may not meet the

    specific requirements of a typical customer. Normally the group of experts having

    the definite skill set is invited to carry out the test at the developers site to identify

    deviations and/or error with respect to the customers need, it is called Alpha

    testing. The tests are carried out under the developers controlled environment.

    Users of the software do theBeta testingof software at the customers site. The users

    then record the problems and suggest the modification that can be incorporated by

    the developer.

    Unsatisfactory test may results in recycling i.e., repetition of one or more phases

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    of development in order to correct poor performance of the system. It may

    require any or all of the following

    Redesign

    Change in the data flow

    Replace equipment

    Debug program Make other adjustment with the system

    The need for recycle is normal and should be expected.

    SDLC STAGE 8: Conversion

    When the testing results are favorable, conversion takes place. The newly developed

    procedures, manuals, forms, files, software and equipment are placed in operation.

    When a system is replacing an existing one, its implementation becomes critical.

    There are four major types of conversion strategies: -

    Parallel Conversion

    - Old and new system run parallel till new system becomes reliable- Costly but safe approach- Best suited for critical applications

    Direct (Changeover) Conversion

    - Old system is replace by a new system- Less costly but more risky as compared to parallel approach

    - Best suited to non-critical applications

    Modular Prototype Conversion (Pilot Study)

    - One department or unit is testing ground- Good for system that is moderately critical

    Phased Conversion

    - New system is slowly incorporated into the operational environment

    - Safe and conservative approach- Well suited to critical applications

    The entire set of activities and sub activities from feasibility study through to

    conversion needs planning and co-ordination. This is also referred to as Project

    Management.

    SDLC STAGE 9 & 10: Operation And Evaluation

    Once a new system is operational evaluation of the system development process

    begins.

    Management: The process of getting activities completed efficiently and

    effectively with and through people.

    Efficiency: The relationship between inputs and outputs, seeks to minimize

    resource costs.

    Effectiveness: Goal attainment

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    Evaluation provides the feedback necessary to assess the value of information and

    the performance of personnel and technology included in the newly designed

    system. This feedback serves two functions

    It provides information as to what adjustments to the information system

    may be necessary.

    It provides information as to what adjustments should be made inapproaching future information systems development projects.

    The operation evaluation is expected to answer the following questions-

    1. Are all transaction processed on time?

    2. Are all values completed accurately?

    3. Is the system easy to work and understand?

    4. Is terminal response time within acceptable limits?

    5. Are reports processed on time?

    6. Is there adequate storage capacity for data?

    The post-development activities involves 1. Preparation of reports including the strength and weakness of the project.

    (The report might review the need for recycling)

    2. List reason for schedule and budget slippages.

    3. Outline liaison and communications problems that occurred during the

    system development

    4. Identifying the mistakes, analyzing the reasons for the mistakes and how

    they could have been avoided.

    When the mistakes are identified they need corrections. Minor changes to the system

    are called system maintenance, while major changes may initiate system

    redevelopment

    No

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    Problem

    Perceive

    d

    Planning

    Feasibility Study

    Acceptable

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    Yes

    Yes

    No

    Yes

    No

    No Yes

    Introduction to Computer & MIS(Lecture Notes)

    MHRDM/MFM/MMM-III

    Prof. DG JHA

    DocumentationDocumentation is the description of the system used to communicate, instruct and

    record information for historical, operational or reference purposes. Documentation

    establishes and declares the performance criteria of a system and provides

    explanation of the system can be used. It should be designed in a format that is

    easily understandable, so that relevant part of it can be used not only by the analysts

    and technical personnels for implementation and modification, but also by users,

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    Worth

    Pursuing

    ?

    Stop

    Determine System

    Requirement

    Design System

    Implement Design

    Test System

    OK?

    Conversion

    Control &

    Operation

    Evaluation

    OK

    ?

    Recycle to apt.

    Point

    Maintenance

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    management, operational personnel and auditors for efficient operations and

    administration.

    Documentation has the production cycle of its own. Activities related to the

    development and maintenance of documentation are:

    No

    Yes

    Documentation must describe who, what, when, where, and how of each system (or

    subsystem) application. Documentation can be produced in modules catering to the

    specific use. This makes information easily accessible to the specific user for which

    they are prepared, and reduce cost of production and maintenance.

    The lists of manuals normally prepared are:

    Users Manual

    o For management

    o For operations

    Application System Manual

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    State Ob ective

    Plan & organize

    with setting up of

    standards

    Pre are

    Test

    Approve &

    Accept

    Distribute

    Use

    Evaluate

    Delay

    OK

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    Policy and Procedures Manual

    Input Preparation Manual

    Operations Manual

    o For management

    o For operator

    Equipment Manualo For each equipment or device

    Programmers Manual

    Program Maintenance Manual

    Special System Manual

    o Operating System

    o Control System

    o Teleprocessing System

    Standards Manual

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