System Analysis & Design - 2

Gagan Deep
Rozy Computech Services
3rd Gate, K.U., Kurukshetra-136119
rozygag@yahoo.com

To develop a systems, such as Management
Information System (MIS), A General Business
System, we need to carry out a detailed systems
analysis and design activity. For this purpose, we
shall have an overview of various stages in this
process.
System development follows an iterative process
that recycles through each stage and almost all
stages overlap each other. This is also termed as
the System Life Cycle.
Gagan Deep, RCS, 3rd Gate, K.U.K.,
rozygag@yahoo.com

SYSTEMS ANALYSIS AND DESIGN PROCESS
The complete process of systems analysis and design
may be considered as consisting of following phases
 Recognition of problem (Initial Investigation) :
What is the problem or opportunity?
 Feasibility study : What are the user’s needs?
What are the benefits?
How can the problem be redefined?
 System analysis : What must be done to solve the
problem?,
What are the facts?
 System design : How must the problem be solved?,
What is system flow?
 System testing : How ready are programs for test?
 Implementation : What is the actual operation?
 Maintenance: Should the system be modified?
rozygag@yahoo.com

RECOGNITION OF PROBLEM
The first stage of any project, sometimes called the
preliminary assessment, is a brief investigation of
the system under consideration to provide to any
project team. The idea of developing a new system
occurs to the user when he recognizes that he has
a problem with the means by which he currently
carries out his business. This awareness marks the
beginning of the recognition of problem phase, as
almost all computer systems replace an existing
system.
 A problem is well defined very rarely. It crops out
with a vague feeling such as too much delay in
order processing, or ‘We must reduce inventory
cost by any means’ or ‘the existing calculation
system is highly error prone’.
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 A system analyst’s first task is to obtain more
crucial information by interviewing and meeting
concerned people. This will clarify how the
problem was felt, how often it occurs, how it
affects the business and which departments are
suffering with this. Analyst does not do detailed
investigation at this stage but he tries to define
the scope of the problem, classifies it and
measures its complexity to ensure that the
problem is important and real enough to require
further investigation.
 A proper understanding of the problem and its
classification enables the systems analyst to
separate symptoms from the real causes It also
helps the analyst to consider it as a systems
problem rather than a business problem and there
by increasing the chances of success in proposing
solutions.
rozygag@yahoo.com

Following are the major classification of the problems:
 The existing system is slow and cannot respond to
information i.e. problem of responsiveness. In this
case the analyst will look to (i) find out present level
of responsiveness and factors contributing to it and
(ii) consider what changes or additions in existing
procedures or resources, utilization would improve
responsiveness and how such changes affect the
organization.
 Originating workload is higher than the volume of
workload handled i.e. problem of throughput. Here
the analyst concentrates on finding the level of
productiveness, its contributing factors, which further
facilitates to improve productivity by better utilization
of resources of by modifications to methods &
resources.
rozygag@yahoo.com

 The present services are very expensive i.e.
problem of economy. The management
intentions could be (i) to reduce cost for same
productivity (ii) to increase productivity but at
present cost level of (iii) discontinue
unproductive operations.
 Problem of Occurrence/ Reliability : At first, the
analyst checks operations, step by step, to see
when and how errors creep up & how to restrict
these errors by using various clarification
checks. For reliability, the system may have to
be designed without any ambiguity and must be
foolproof, as system failures result in loss of
business.
rozygag@yahoo.com

 There is a problem of information, where the
analyst would be concerned with organization of
available information, its accessibility for
decision making. These types of problems have
close relationship with the ways of data storage
and organization.
 Problem of efficiency. This problem is
interrelated to all the above problems. The
analyst must create a proper balance between all
the contributing factors like response time,
workload volume, cost of processing, and
information needs etc.
 Problem of security of information : Here the
analyst tries to devise controls over accessibility
of information.
rozygag@yahoo.com

FEASIBILITY STUDY
If the Study proposal is accepted by management, it will
lead to an investigation of the existing system or
problem area, conducted in close collaboration with user
management and in sufficient depth to establish in broad
terms the technical, operational and economic feasibility
of proposal. Having recognised the problem areas, the
next step is to carry out an overall analysis of the system
requirements in terms of its :
 The Input data  Type of processing needed and
 The output reports
This needs a detailed feasibility study to be carried out
by the System Analyst.
To carry out the analysis of the existing system the
system analyst may take the help of any of the following
techniques:
 Interviews Questionnaires  Observation
rozygag@yahoo.com

This would help him to have an in-depth study
of the existing system and understand its
strengths and weakness and the requirements
of the new proposed system.
Three phases of feasibility study is used are as
follows:
 Technical feasibility  Operational feasibility
 Economic feasibility.
 The technical feasibility is concerned with the
available hardware and software resources
whether they meet the given requirements of
the analysed system or not. It may also invoke
the study of new alternatives to solve the given
problem.
rozygag@yahoo.com

 The operational feasibility is to take the
operational staff into confidence. The success of
a good system depends upon the willingness of
the operating staff. They should not have any
fears like uncertainty about their jobs or control
over the working which develops a bias in their
minds towards the computerised systems. This
acts as a big barrier in the successful
implementation of any project.
 The economic feasibility deals with the study of
cost benefit analysis. All the costs of the new
proposed system are compared with the benefits
which can be obtained for the management
approval. The benefits may be quantitative or
qualitative in nature.
rozygag@yahoo.com

The following steps are used in the complete
feasibility study:
 Study the existing system
 Define the scope of the proposed system
 Study the strengths and weakness of the
existing system
 Study various alternatives
 Carry out feasibility studies
 Get the management approvals
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SYSTEM ANALYSIS
 Detailed investigation should be conducted with
personnel closely involved with the area under
investigation, according to the precise terms of
recognisation of problem arising out of the
feasibility study report.
 The objectives at this stage are to provide
solutions to stated problems, usually in the form
of a specification to meet the users’
requirements; and to make recommendations
for a new computer-based system.
 Analysis is an iterative and progressive process,
examining information flows and evaluating
various alternative design solutions until a
preferred solution emerges.
rozygag@yahoo.com

It involves an in-depth study of the existing
system with to the following :
 Organization structure
 Sources of data origination
 flow of data within the organization
 Accuracy and timeliness aspect of the data
handling process.
 The process of data storage
 The type of data processing
 The reports being generated at various stages
 The new user requirements
 Estimation of resources needed to design the
new system
rozygag@yahoo.com

SYSTEM DESIGN
System design is a creative as well as a technical activity.
This stage is the most time and resource consuming. It is
the real technical activity which involves the design of the
system around the computer. It includes many steps such
as :
 The preparation of system outlines chart
 Design of input forms, validation procedures and data
preparation procedures
 Design of output reports
 Code designing
 Detailed file layout and file designing
 Selection of system software and selection of
programming languages or database to be used
 Computer procedure design
 Program development
 Testing of the programs
 Security and Controls
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SYSTEM TESTING
This phase involves the testing of overall system.
 First, it test the parts separately and finally the
system as a whole. Each subsystem or independent
module and program is tested first and then through
the interfaces to other subsystems the complete
system is tested.
 This is the most important phase as the system
analyst has to get the user certification for the
accuracy of the system. In other words, it may also be
referred as the acceptance testing by the user.
 Such a testing should be carried out by the user, the
users representative, the system analyst, the
standards group, the external systems auditor or any
combination thereof.
 The test data is normally prepared by the user to
check for all possible combination of correct data as
well as the wrong data which should be trapped by
the system and reported as an error.
rozygag@yahoo.com

IMPLEMENTATION
Implementation is concerned with those tasks
leading immediately to a fully operational system.
 It involves programmers, users and operations
management, but its planning and timing is a prime
function of systems analysis.
 After the system has been certified by the user, it
comes to the stage of implementation.
 It involves many issues like preparation for the
change over to the new system and then the actual
change over.
 Preparation of the site and installation of the
facilities, training of the staff, Preparation of data
files etc. are the various steps involved which might
require the involvement of the system analyst, the
user as well as the operational management.
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Changeover : After all the preparations for the system
implementation are completed, comes the stage of
actual changeover. This involves the usage of new
system which has been developed and thoroughly
tested. Some of these changeover approaches are as
given below.
 Direct Changeover  Parallel Running  Pilot
Running
Direct Changeover :In this method, the old system is
scrapped or withdrawn the moment new one is put
into use. For example if it is a Banking System, this
type of changeover would mean that the manual
record keeping is stopped and is directly handled
through the new computerized system. This could
lead to some problems if the new system does not
behave as expected. This may be the result of some
unforeseen situations which had not been taken
care of during the system analysis and design
phase.
rozygag@yahoo.com

Parallel Running : Parallel running is a method of
submitting a new system to a final acceptance
test, in which data is processed using both the
old and new systems simultaneously. The result
of two systems are compared and any
discrepancies examined to see whether the
computer system is at fault.
The main drawback of this method is extra cost
because the user staff will have to work with two
systems i.e. old and new.
Pilot Running : Pilot running is an alternative to
parallel running, and consists of the allocation of
a certain amount of work to be performed by the
computer while the remainder is done by old
method. The amount of work performed on the
computer is gradually increased until the
changeover is complete and the old system is
discontinued.
rozygag@yahoo.com

MAINTENANCE
 Once the system has settled down and been running
for some time, the systems analyst may be involved
in amendment procedures to adapt the system to
changing conditions;
 in auditing the system to check that the stated
objectives of the system are still valid in the
present environment; and
 in evaluating the achievement of those objectives.
 This is an ongoing exercise after the system has
been implemented. The real life would is never
static. Its requirements and objectives keep
changing. So shall be the system which have been
designed primarily to meet those objectives.
 Thus the system analyst has to keep on carrying out
changes and modification into the system, a stage
called normally as system maintenance.
rozygag@yahoo.com

 As shown in figure (next slide), system development
follows an iterative process that recycles through
each stage and almost all stages overlap each other.
This is also termed as the SYSTEM LIFE CYCLE.
 It is in the nature of system that they share a
common life cycle pattern. After a system has been
in operation for a number of years, it gradually
decays and becomes less and less effective because
of the changing environment to which it has to
adapt. For a time it is possible to overcome
problems by amendments and minor modifications
to the system but eventually it will be necessary to
acknowledge the need for fundamental changes. At
this stage the systems analyst becomes involved
and investigates the problems and the requirements
have been adequately identified, a new system can
be designed and subsequently implemented.
rozygag@yahoo.com

rozygag@yahoo.com

PRINCIPLES OF SYSTEM DESIGN
 There are some of the do’s and dont’s that help in
designing an effective system. Some of these are :
 Principle of modular design : The system should be
broken down into smaller parts and then each part shall
be designed as a separate module. this help in paying
equal attention to all parts rather than neglecting one and
over attending another.
 Principle of sub system integration : The modules
designed separately need to be integrated in a unified
whole to provide synergetic effect only the proper
integration will lead to effective working of system.
 Principle of minimum information : A good system should
be designed in a way that supplies minimum amount of
information required for decision making to the user as
any additional amount of information will burden the
system for resources. However, if any additional
information is required for better decision making, system
should provide for it through query system which supplies
information on demand rather than on routine basis.
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 Principle of user based design : The system should be
user friendly. It should not be rigid to supply only
fixed information but should be flexible enough to
give information to satisfy users.
 Principle of manager-analyst co-operation : Manager
is the user of information. On the other hand Analyst
is the person responsible for the design of MIS. The
two often fail to understand each other’s
requirements and come into conflict. A good design
require the active co-operation of both for which they
might have to for go their biases.
 Principle of cost effective design : Cost effectiveness
is the most important criterion for any system, if a
system cost exceeds its benefits, it will be of no use.
For this purpose we will do a cost benefit analysis.
rozygag@yahoo.com

SYSTEMS ANALYSIS TOOLS
 The first and obvious purpose of a system
analyst’s work is to establish precisely
 What the system is intended to achieve?
 What information enters it, leaves it and is held
within it?
 Only when he knows to what objectives a system
is directed, and in a position to change or replace
it.
 The second purpose is to enable him to
communicate with management at all levels, so
that the findings of his investigations can be
confirmed and possible changes discussed on the
basis of common knowledge.
 The third purpose is to design the system i.e.
enter into system design stage.
rozygag@yahoo.com

Now we are discussing a few tools which can be
used to establish these requirements of a
system analyst’s job.
 Graphical Tools
 Organisation Chart
 Fact Finding
 Interviews
 Questionnaires
 Observations
 Data Dictionary
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PROS AND CONS OF SYSTEM ANALYSIS TOOLS
Which tool is the best depends on a number of factors:
the number and complexity of the problem, the number
of actions resulting from the decisions, and the ease of
use. In reviewing the benefits and limitations of
each tool, we come to the following conclusions:
 The primary strength of the DFD is its ability to
represent data flows. It may be used at high or low
levels of analysis and provides good system
documentation. However, the tool only weakly shows
input and output detail.
 The data dictionary helps the analyst simplify the
structure for meeting the data requirements of the
system. If may be used at high or low levels of
analysis, but it does not provide functional details,
and it is not acceptable to many non-technical users.
rozygag@yahoo.com

 Structured English is best used when the
problem requires sequences of actions with
decisions.
 Decision trees are used to verify logic and in
problems that invlove a few complex
decisions resulting in a limited number of
actions.
 Decision trees and decision tables are best
suited for dealing with complex branching
routines such as calculating discounts or
sales commissions or inventory control
procedures.
A decision table is perhaps the most useful tool
for communicating problem to the user.
rozygag@yahoo.com

Gagan Deep
Rozy Computech Services
3rd Gate, K.U., Kurukshetra
rozygag@yahoo.com
rozygag@yahoo.com

System Analysis & Design - 2

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