Information System Analysis and Design, Information System Development Life Cycle (SDLC), System Implementation, System Testing, Documentation, Conversion Methods.
2. INFORMATION SYSTEM ANALYSIS AND
DESIGN.
INFORMATION SYSTEM DEVELOPMENT
LIFE CYCLE.
HARDWARE AND SOFTWARE
ACQUISITION.
SYSTEM TESTING.
DOCUMENTATION AND ITS TOOLS.
CONVERSION METHODS.
3. Information Systems Analysis:
• Identification, Understanding, and Examining the
existing system for identifying problems and
recommending feasible suggestions.
• Collecting and Interpreting facts to overcome the
weaknesses of the system.
OBJECTIVES:
1. To know how a system currently operates.
2. To identify the user’s requirement in the
proposed system.
4. Characteristics of System Analysis:
• Top-Down Approach.
• Use of tools and techniques.
• Abstraction of models.
• User’s role.
• Iterative development.
• Use of advanced technology.
• Can be used with prototyping.
5. Need for System Analysis:
• System Objective.
• System Boundaries.
• System Importance.
• Nature of the system.
• Role of the system as an interface.
• Participation of users.
• Understanding of resource needs.
• Assessment of feasibility.
6. Information Systems Design:
System analysis finds “what” has to be done. System
design says “how” it’ll be done.
OBJECTIVES:
1. Support business activities.
2. Ensure user requirements are met.
3. Provide ease of use.
4. Specify logical design elements.
5. Provide software specification.
6. Conform to design standards.
7. System Design Methods:
• Problem Partitioning.
• Structured Design.
• Top-Down Design.
System Design Stages:
1. Logical/ Conceptual/ External Design.
2. Physical/ Detailed/ Internal Design.
8. Information System Development Life Cycle:
SDLC is a multi-step process or a cycle
used to design, develop and test information
system solutions.
9. • Raise questions about the information system.
• Screen, select, and study the preliminary solution.
Steps in Stage 1:
1. Information system planning.
a) Strategic Planning
b) Requirement Analysis.
c) Resource Allocation.
d) Project Planning.
2. Feasibility study.
3. Feasibility report.
Stage1- Planning or Investigation.
10. Stage 2- Analysis.
The process of gathering and interpreting facts,
diagnosing problems and recommending improvements.
Stage 3- Design.
Specifies how the system will accomplish the
objective.
• Logical Design- Functional features described
independently of computer platform.
• Physical Design- Logical specifications
transformed to technology.
11. Stage 4- Implementation.
The realization of a technical specification or algorithm as
a program through programming and deployment.
Stage 5- Maintenance.
Monitoring, evaluating, and modifying systems.
• To correct errors.
•To keep the system current.
•To improve the system.
12. SYSTEM IMPLEMENTATION
Involves hardware & acquisition, software
development, testing of programs & procedures,
development of documentation, and conversion.
13. Hardware & Software Acquisitions:
Suppliers present bids on system specifications
developed during design stage. Companies evaluate the
proposals on how well it meets user’s specifications.
1. Hardware Evaluation: Investigate specific
physical and performance characteristics for
each component to be acquired. Capital
expenditure analysis is one of the factors.
2. Software Evaluation: Performance, cost,
reliability, availability, compatibility, modularity,
technology, ergonomics and support should be
evaluated.
15. System Testing:
Testing is the process of executing a program with the
intent of finding errors.
‘Test Case’ describes an input description and an
expected output description.
‘Test Suite’ is the set of all test cases with which a given
software is to be tested.
Purpose:
• Response Time.
• Volume.
• Stress Testing.
• Recovery and Security.
• Usability Documentation and Procedure.
16. Types Of Testing:
1. Unit Testing
2. Module Testing
3. Sub-System Testing
4. System Testing
5. Acceptance Testing
17. DOCUMENTATION AND ITS TOOLS OF SAAD
Documentation is a process of recording the information
for any reference or operational purpose.
It helps users.
Types Of Documentation:
1. User Documentation (User Manual).
2. Technical Documentation (System Requirement).
18. USER DOCUMENTATION (USER MANUAL):
o Flow chart.
o Manual data processing.
o Methods for controlling and revising the system.
o Output report and formats.
o Forms.
20. USES OF DOCUMENTATION:
o Communication
o Maintenance
o Self instructional
o Trouble shooting
o Control
o Evaluation
21. CONVERSION STRATEGIES
Conversion means switch on to a new system from an
existing system.
1. Direct Cut Over
2. Parallel Method
3. Pilot Method
4. Phased Method
Types Of Conversion Strategies:
22. 1. Direct Cut Over.
In this method on a particular day new system is
immediately replaced with new system in whole
organization .
ADVANTAGES DISADVANTAGES
a. It costs a less amount of
money as everything has to
just set up for once.
b. It’s very easy to make change
over.
a. If the system has not been
implemented properly the new
system may fail to work and
this will affect the whole
organization.
b. It’s very difficult to detect
small errors in the new system.
23. 2. Parallel Method.
It is the method in which existing system and new
systems are made to run or work simultaneously or in
parallel direction.
ADVANTAGES DISADVANTAGES
a. Small, minor errors can
be easily seen.
b. Companies can fix any
problems with the new
system before ending the
previous system.
a. Very costly as two
systems are being
operated simultaneously.
b. Operating two systems
simultaneously is time
consuming and stressful
as there is more work
involved, such as
creating more reports.
24. 3. Pilot Method
It is the method in which new system is implemented in a
single branch or department to have exact output from
the system. This method is very useful for the companies
having multi locations.
ADVANTAGES DISADVANTAGES
a. It is an economic
conversion
strategy.
b. It reduces risk.
a. Sometimes some
operations remain
untested.
25. 4. Phased Method
It is the method in which a part of system is build to
for all users. It replaces the old system in stages.
ADVANTAGES DISADVANTAGES
a. Negligible chance of
any type of problem
in the system as it is
tested in every stage.
b. More user friendly.
a. It needs a lot of time
for full implementation
of system.