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Lesson#17
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Planning for System Development
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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
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Scope of software
development – certain selected areas or the entire organization.
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How to get the project
done – in-house committee or hired consultants.
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How much resource and
time commitment can be made.
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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.
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Orientation
-- This start-up phase is required to
establish the scope of the plan and the methodology
and techniques to be applied
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Assessment
-- Major steps in this phase are
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Confirm business
direction and drivers;
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Review technology
trends; outline future requirements;
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Inventory existing
information systems; and
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Develop an assessment of
what is needed.
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In the concluding step
of this phase there should be a well-developed assessment of the current and
future business needs,
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Strategic Plan
--
This phase commences with
developing the vision and desired future positioning of
information technology within the organization.
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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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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.
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A manual information
system is to be computerised.
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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
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Structure
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Methods
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Controls
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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
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Well
structured/Structured -- constrained problems with convergent solutions, limited
number
of rules and principles within well-defined parameters.
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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.
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Investigation on
existing system
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Definition of system
requirements
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Specifying performance
criteria for the system
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Detailed cost budget
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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.
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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
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Draw representatives
from the departments affected by the project
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At least one person must
have a detailed knowledge of computers and systems design (called
system analyst).
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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
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Consultants from the
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