ANALYSIS PHASE OF BUSINESS SYSTEM
DEVELOPMENT METHODOLOGY
INTRODUCTION
 System Analysis – is a term that describes the early
phases of systems development.
 problem solving technique that decomposes a system
into its component pieces for the purpose of studying
how well those component parts work & interact to
accomplish their purposes.
System analysis approaches
 There are 4 system analysis approaches;
 Model driven analysis approach
 Accelerated analysis approach
 Requirements discovery methods
 Business process redesign methods
Model Driven Analysis Approaches
 Emphasizes the drawing of pictorial system models to
document & validate both existing & proposed system.
 The system model becomes the blueprint for designing &
constructing an improved system.
 Example of software : VISIO
Structures Analysis
 Was one of the first formal approach for system analysis of
business information system.
 Used to either analyze an existing system, define business
requirements for new system or both.
Model Driven Analysis Approaches
Information Engineering
 Model driven & data centered approach to plan,
analyze & design information systems.
 Consists of pictures that illustrate & synchronize the
system’s data & processes.
 Said to be data-centered paradigm because it
emphasizes the study & requirement analysis of data
requirements before those of the process & interface
requirements.
 This is based on the belief that data is a corporate
resources that should be planned & managed.
Model Driven Analysis Approaches
Object Oriented Analysis
 Is a technique that integrates data & process concerns
into constructs called objects.
 Consists of pictures that illustrates the system’s objects
from various perspectives such as structure &
behaviour.
 Unified Modeling Language (UML) provides a
graphical syntax for an entire series of object models.
Accelerated Analysis Approaches
 Emphasize the construction of prototypes by rapidly
identifying business & user requirements for a new
system.
 Emphasizes the interface building blocks in the
information system framework by constructing sample
forms & reports.
 Prototype – a small scale, incomplete but working
sample of desired system.
Accelerated Analysis Approaches
Discovery Prototyping
 Uses rapid development technology to help users discover
their business requirements by having them reach to quickand- dirty implementation of those requirements.
Rapid Architecture Analysis
 An accelerated analysis approach that also builds a system
models.
 Attempts to derive system models from existing systems or
discovery prototype.
 It is made possible by reverse engineering technology that
is included in many tools such as CASE & programming
languages.
Accelerated Analysis Approaches
 Reverse engineering technology reads the program
code for an existing database, application program,
user interface & automatically generates the equivalent
system model.
 The resulting system model can be further edited by
system analyst & users to provide a blueprint for a new
& improved system.
Requirement Discovery Methods
 Includes those techniques to be used by system analyst
to identify or extract system problems & solution
requirements from the user community.
Fact-finding Techniques
 An essential skill for all system analysts.
 Classical set of techniques used to collect information
about system problems, opportunities, solution
requirements & priorities.
Accelerated Analysis
Approaches
 Fact finding techniques;
 Sampling of existing documentation, reports, forms, memos
 Research of relevant literature, site visits
 Observation on the current system & work environment
 Questionnaires & surveys of the management & users
 Interviews of the appropriate managers, users & technical
staffs.
Business Process Redesign
Methods
 Business process redesign – the application of system
analysis methods to the goal of dramatically changing &
improving the fundamental business processes of an
organization, independent of information technology.
 Suitable for a study of existing business processes to
identify problems & inefficiencies that is addressed in
requirements for new / improved system.
The Preliminary Investigation
Phase
 Investigation is done by system analyst to study the
systems request & recommend specific action.
 The analyst gathers fact about the problem /
opportunity, project scope & constraints, project
benefits & estimated development time & cost.
 The end product of the investigation is a report to the
management.
Steps in the Preliminary
Investigation
Step 1:
Understand the problem / opportunity
Step 2:
Define project scope & constraints
Step 3:
Performs fact-finding
Step 4:
Determine feasibility
Step 5:
Estimate development time & cost
Step 6:
Present result/recommendation to management
Steps in the Preliminary
Investigation
Step 1: Understand the problem / opportunity
 System analyst might need to develop a business profile.
 Analyst will need to understand & know how the
modifications will affect the business operation or system
even when it’s a small alteration.
Step 2: Define the project scope & constraints
 Means to define boundaries/extent of the project being as
specific as possible.
 Projects that expands gradually without specific
authorization is called = project creep
Steps in the Preliminary
Investigation
 Types of constraints ; present, future, internal, external,
mandatory & desirable.
Step3: Perform fact-finding
 Analyst will perform this step using various techniques
such as;
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Analyze organization charts – to understand how departments
functions & identify the individual involved
Conduct interview – interviewing the identified individual.
Review current documentation – analyst should check whether the
documentation received is accurate & complete
Observe operation – use statistic technique to check the frequency
Carry out a user survey – especially when it involves larger group.
Steps in the Preliminary
Investigation
Step4 : Determine feasibility
 To determine economic feasibility.
Step5 : Estimate time & cost
 To determine cost & time the following need to be
addressed:
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What information needed & how to gather & analyze?
Source of information to use & the constraints to use it?
How many will be interviewed & how much time & cost for it.
How much cost to alayze the information gathered & prepare final
report.
Steps in the Preliminary
Investigation
Step6 : present results & recommendations to
management
 If minor problem then recommendation is given
without further analysis, but if the problem is big then
further analysis is needed (development phase)
Problem Analysis Phase
 Provides the analyst a better understanding of the
problems, opportunities & directives that triggered the
project.
 The goal of this phase is to study & understand the
problem domain well enough to analyze its problems,
opportunities & constraints.
Steps in Problem Analysis Phase
 Analyst must follow a series of steps:
 Step 1 – study the problem domain
 Step2 – analyze problems & opportunities
 Step3 – analyze business process
 Step4 – establish system improvement objectives
 Step 5- update the project plan
 Step 6 – present findings & recommendations to
management
Steps in Problem Analysis Phase
 Step 1 – study the problem domain
 Attempts to learn about the current system
 Step2 – analyze problems & opportunities
 To perform this step, project team must work with
system owners & system users
 Cause & effect analysis is a technique in which problems
are studied to determine their causes & effects.
Steps in Problem Analysis Phase
 Step3 – analyze business process
 Analyze business needs – to clearly define the business &
system requirements.
 Define business solution – IT experts define in the form of
programs 7 databases, business people define in procedures
to fulfill business mission.
 Test business solution – evaluating whether the solution
fulfills the business need.
 Step4 – establish system improvement objectives
 Any improvement to the system will be measured &
constraints identified. Criteria for success measured in term
of objectives
Steps in Problem Analysis Phase
 Step 5 – update the project plan
 This task is triggered by completion of the system
improvement objectives.
 Initial project plan = input, updated project plan = output
 Step 6 – present findings / recommendations
 This task is triggered by the completion of the updated
project plan.
Requirements Analysis Phase
 Defines the business requirements for a new system.
 Final deliverables & milestones is to produce a
business requirements statement that will fulfill the
system improvement objectives.
Steps in Requirements Analysis
Phase
 Steps are as follows:
 Step 1 – define requirements
 Step2 – analyze functional requirements
 Step3 – trace & complete requirements
 Step4 – prioritize requirements
 Step5 – update the project plan
 Step6 – outgoing requirement management
Steps in Requirements Analysis
Phase
 Step1 : define requirements
 A functional requirement – a description of activities &
services a system must provide (input, output, stored data &
processes)
 Non functional requirement – description of other features,
characteristics & constraints that define a satisfactory
system (performance, budgets, cost)
 Step2 : Analyze functional requirements
 System modeling – graphical representation of concept or
process that system developers can analyze, test & modify
 Prototyping – creation of early working version of the
information system or its components.
Steps in Requirements Analysis
Phase
 Step3 – Trace & complete requirements
 Tracing each system model / prototype back to the
functional requirement to ensure all functional
requirements are fulfilled.
 Step4 – prioritize requirements
 Timeboxing – technique that delivers information
system’s functionality & requirements through
versioning.
Steps in Requirements Analysis
Phase
 Step5 : update the project plan
 The completed business requirements statement
completes the task, as well as the requirement analysis
phase.
 Step6 : ongoing requirement management
 Requirement management defines a process for
everyone involved in the system development that
specifies how changes are to be requested &
documented, how to be logged & tracked, etc
Decision Analysis Phase
 Identifies candidate solutions, analyses those
candidate solutions & recommends a target system
that will be designed, constructed & implemented.
Steps in Decision Analysis
Phase
 Steps are as follows ;
 Step1 – identify candidate solutions
 Step2 – analyze candidate solutions
 Step3 – compare candidate solutions
 Step4 – update the project plan
 Step5 – recommend a system solution
Steps in Decision Analysis
Phase
 Step 1: identify candidate solution
 System owners & users may not be directly involved in the
task, but they may contribute ideas & opinions that start the
task.
 Step2: analyze candidate solution
 Each candidate solution must be analyzed for feasibility.
 4 criteria:
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Technical feasibility
Operational feasibility
Economic feasibility
Schedule feasibility
Steps in Decision Analysis
Phase
 Step3 : Compare candidate solution
 The deliverables of this task is the solutions to be
recommended. If more than one solution is
recommended, priorities should be established.
 Step4 : update the project plan
 System analyst are adjusting scope accordingly, so based
on the solution recommended, analyst should reevaluate project scope & update project plan accordingly
Steps in Decision Analysis
Phase
 Step6 : Recommend a solution
 This task is triggered by the completion of the updated
project plan.
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CHAPTER 5