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CS507 - Information Systems - Lecture Handout 17

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Planning for System Development

The management should prefer to have a plan for IT development so as to help it to take various software development projects in a structured way. At the very start, planning is done by the management regarding following issues

  • Scope of software development – certain selected areas or the entire organization.
  • How to get the project done – in-house committee or hired consultants.
  • How much resource and time commitment can be made.
  • Any written policy on which model is needed to be followed for software development.

IT planning provides a structured means of addressing the impact of technologies, including emerging technologies, on an organization. Through the planning process, relevant technologies are identified and evaluated in the context of broader business goals and targets. Based on a comparative assessment of relevant technologies, the direction for the organization can be established. Business planning is an accepted responsibility of management. Plans provide a direction and framework for action. Plans enunciate business goals and the actions that need to be initiated to achieve those goals including related benefits, resources and timeframes.

Increasingly, information technologies not only support but, also may drive or enable business strategies. In this context information technologies are an integral part of the business planning process itself. If such potential is evident after the completion of the business plan, then the business plan must be revisited and, if appropriate, revised.

Phases of IT planning

Although information technology plans are unique, the planning process and the underlying activities are similar.

  • Orientation -- This start-up phase is required to establish the scope of the plan and the methodology and techniques to be applied
  • Assessment -- Major steps in this phase are
    • Confirm business direction and drivers;
    • Review technology trends; outline future requirements;
    • Inventory existing information systems; and
    • Develop an assessment of what is needed.
    • In the concluding step of this phase there should be a well-developed assessment of the current and future business needs,
  • Strategic Plan -- This phase commences with developing the vision and desired future positioning of information technology within the organization.
  • Tactical Plan -- The selected strategies are divided into a series of projects which are scheduled for implementation depending upon relative priorities and resource availability. The planning process is concluded by recommending a monitoring and control mechanism.

What is System Development?

System development refers to the structuring of hardware and software to achieve the effective and efficient processing of information. Information systems are developed keeping in view the needs to be met. There can be two reasons for system development.

  • A manual information system is to be computerised.
  • An already computerised information system is to be replaced with a system that addresses the growing and changing needs of the organization or the old system has become too slow or there are newer more efficient and user friendly development tools are available.

In both the above mentioned situations, the phases followed for system development would be the same.
The extent of system study, analysis & design may depend on the fact whether the existing system is manual or computerised. To develop systems, various development models or techniques are deployed. Let us understand why these development models are used.

Models Used for System Development

Initially software development consisted of a programmer writing code to solve a problem or automate a procedure. Nowadays, systems are so big and complex that teams of architects, analysts, programmers, testers and users must work together to create the millions of lines of custom-written code that drive our enterprises. To manage this, a number of models for system development have been created. The most famous of these models is the system development lifecycle model (SDLC) or Lifecycle Models.

Systems Development Life Cycle

System Development Life Cycle (SDLC) is the overall process of developing information systems through a multi-step process from investigation of initial requirements through analysis, design, implementation and maintenance. SDLC is also known as information systems development or application development. SDLC is a systems approach to problem solving and is made up of several phases, each comprised of multiple steps. It describes the stages a system passes through from inception until it is discarded or replaced. SDLC provides

  • Structure
  • Methods
  • Controls
  • Checklist

Project lifecycle vs. SDLC

The systems development life cycle is a project management technique that divides complex projects into smaller, more easily managed segments or phases. Segmenting projects allows managers to verify the successful completion of project phases before allocating resources to subsequent phases. Although System development can be seen as a project in itself, but the attribute that makes system development different from regular projects is that a project has a definite end and it is unlikely that ongoing maintenance will be included in the scope of the project but this falls in the definition of SDLC.

Types of System Development Life-Cycle Model

The concept of system development lifecycle model has been explained in various shapes and forms. The concluding form follows the same spirit except for minor differences.

Waterfall model / Classic lifecycle/ Linear Sequential Model

The waterfall model is a software development model (a process for the creation of software) in which development is seen as flowing steadily downwards (like a waterfall) through the various phases

Incremental Models

In incremental models, software is built not written. Software is constructed step by step in the same way a building is constructed. The products is designed, implemented, integrated and tested as a series of incremental builds, where a build consists of code pieces from various modules interacting together to provide a specific functional capability and testable as a whole.

Iterative Models

In these models customer feed back is taken at each phase and project is modified accordingly – if need be.
Prototypes are used in these models.

Need Assessment

Information systems are usually developed on need-basis, that is, problems and opportunities arise and render system development necessary. In this phase the stakeholders must attempt to come to some understanding of the nature of the problem or opportunity they are addressing. Issues which can be considered in this phase are. Is the problem

  • Well structured/Structured -- constrained problems with convergent solutions, limited number of rules and principles within well-defined parameters.
  • Unstructured -- multiple solutions, fewer parameters, and contain uncertainty about which concepts and rules.

Should formal terms of reference be prepared and approved by the steering committee or project committee? This depends on the size, impact and cost of the system being prepared. The TOR usually covers following aspects.

  • Investigation on existing system
  • Definition of system requirements
  • Specifying performance criteria for the system
  • Detailed cost budget
  • Draft plan for implementation

If the problem is decided to be addressed and the level of acceptance that exists among the stakeholders on the need of change. The level of technological uncertainty the proposed solution to the problem/opportunity has. The most critical phase is the agreement of the stakeholders on the definition of problem and parameters of solution.

Entry and Feasibility Study

The purpose of this phase is to obtain a commitment to change and to evaluate whether cost effective solutions are available to address the problem or opportunity that has been identified. Following examples can be considered to explain this situation.

  • Say a problem has been recognized by a group of users. They believe they can design and implement a solution themselves using a high level language. Their proposed system will have little impact on others within the organization, nor will it be material from the viewpoint of the overall organization. In this situation, the users are already motivated to bring about change. Thus activities to accomplish successful entry are minor or unnecessary.
  • On the other hand, consider a solution where potential solutions will have a widespread impact on the overall organization. Activities to accomplish successful entry are now critical. Information systems professionals must seek to establish themselves as legitimate change agents among the stake holders. Moreover they must seek to foster among the stakeholders a commitment to change. If potential solutions will have a significant impact on task and social systems, a spirit of collaborative analysis and evaluation among stakeholders must be developed.

Once the entry is successful, a preliminary study can be carried out to evaluate the feasibility of the new system. A Feasibility study team should be constituted

  • Draw representatives from the departments affected by the project
  • At least one person must have a detailed knowledge of computers and systems design (called system analyst).
  • At least one person should have a detailed knowledge of
    1. The organization
    2. How current system operates
    3. Information needs of the system
    4. Defects in the existing system
  • Consultants from the outside