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Information System (CS507)
LESSON 17
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.
17.1 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
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Information System (CS507)
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.
17.2 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.
17.3 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.
17.4 Types of System Development Life-Cycle Model
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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.
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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
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Table of Contents:
  1. Need for information, Sources of Information: Primary, Secondary, Tertiary Sources
  2. Data vs. Information, Information Quality Checklist
  3. Size of the Organization and Information Requirements
  4. Hierarchical organization, Organizational Structure, Culture of the Organization
  5. Elements of Environment: Legal, Economic, Social, Technological, Corporate social responsibility, Ethics
  6. Manual Vs Computerised Information Systems, Emerging Digital Firms
  7. Open-Loop System, Closed Loop System, Open Systems, Closed Systems, Level of Planning
  8. Components of a system, Types of Systems, Attributes of an IS/CBIS
  9. Infrastructure: Transaction Processing System, Management Information System
  10. Support Systems: Office Automation Systems, Decision Support Systems, Types of DSS
  11. Data Mart: Online Analytical Processing (OLAP), Types of Models Used in DSS
  12. Organizational Information Systems, Marketing Information Systems, Key CRM Tasks
  13. Manufacturing Information System, Inventory Sub System, Production Sub System, Quality Sub system
  14. Accounting & Financial Information Systems, Human Resource Information Systems
  15. Decision Making: Types of Problems, Type of Decisions
  16. Phases of decision-making: Intelligence Phase, Design Phase, Choice Phase, Implementation Phase
  17. Planning for System Development: Models Used for and Types of System Development Life-Cycle
  18. Project lifecycle vs. SDLC, Costs of Proposed System, Classic lifecycle Model
  19. Entity Relationship Diagram (ERD), Design of the information flow, data base, User Interface
  20. Incremental Model: Evaluation, Incremental vs. Iterative
  21. Spiral Model: Determine Objectives, Alternatives and Constraints, Prototyping
  22. System Analysis: Systems Analyst, System Design, Designing user interface
  23. System Analysis & Design Methods, Structured Analysis and Design, Flow Chart
  24. Symbols used for flow charts: Good Practices, Data Flow Diagram
  25. Rules for DFDs: Entity Relationship Diagram
  26. Symbols: Object-Orientation, Object Oriented Analysis
  27. Object Oriented Analysis and Design: Object, Classes, Inheritance, Encapsulation, Polymorphism
  28. Critical Success Factors (CSF): CSF vs. Key Performance Indicator, Centralized vs. Distributed Processing
  29. Security of Information System: Security Issues, Objective, Scope, Policy, Program
  30. Threat Identification: Types of Threats, Control Analysis, Impact analysis, Occurrence of threat
  31. Control Adjustment: cost effective Security, Roles & Responsibility, Report Preparation
  32. Physical vs. Logical access, Viruses, Sources of Transmissions, Technical controls
  33. Antivirus software: Scanners, Active monitors, Behavior blockers, Logical intrusion, Best Password practices, Firewall
  34. Types of Controls: Access Controls, Cryptography, Biometrics
  35. Audit trails and logs: Audit trails and types of errors, IS audit, Parameters of IS audit
  36. Risk Management: Phases, focal Point, System Characterization, Vulnerability Assessment
  37. Control Analysis: Likelihood Determination, Impact Analysis, Risk Determination, Results Documentation
  38. Risk Management: Business Continuity Planning, Components, Phases of BCP, Business Impact Analysis (BIA)
  39. Web Security: Passive attacks, Active Attacks, Methods to avoid internet attacks
  40. Internet Security Controls, Firewall Security SystemsIntrusion Detection Systems, Components of IDS, Digital Certificates
  41. Commerce vs. E-Business, Business to Consumer (B2C), Electronic Data Interchange (EDI), E-Government
  42. Supply Chain Management: Integrating systems, Methods, Using SCM Software
  43. Using ERP Software, Evolution of ERP, Business Objectives and IT
  44. ERP & E-commerce, ERP & CRM, ERP Ownership and sponsor ship
  45. Ethics in IS: Threats to Privacy, Electronic Surveillance, Data Profiling, TRIPS, Workplace Monitoring