Management information system-system development methods,useful for MBA second semester MIS portions(calicut university),methodologies of system developement

1. BY
SACHIN SREEKUMAR

2. SDLC
 An information system is built with an objective and
the activities performed to build the system are called
System Development Life Cycle(SDLC).
 SDLC consists of:
1)Analysis 4)Implementation
2)High-level design 5)Testing
3)Detailed Design 6)Deployment

3. BACKGROUND
 Large scale system development projects were
attempted by US military.
 They developed a framework of a sequence of stages
for developing a system. It is called as SDLC.
 But the MIS oriented SDLC is different from others
that it is more business oriented.

4. SYSTEM DEFINITION PHASE
 System takes its shape and form logically.
 A series of stages and steps are taken to develop a set of
guidelines.
 The key steps in the phase are:
1)Preliminary analysis
2)Feasibility study
3)Information analysis
4)System design

5. PRELIMINARY ANALYSIS
 Normally conducted before an information system is
designed.
 Sometimes called preliminary investigation.
 First step in the life cycle of a system.
 Performed to understand requirements, objectives,
scope and boundaries of the proposed system.

6. STEPS OF PRELIMINARY ANALYSIS
 Steps taken under preliminary analysis are:
1)Assessment and survey of situation
2)Analysis of current system(if any)
3)Analyse system requirements and provide specifics

7. FEASIBILITY STUDY
 Examines if a system can be developed successfully
given the technical endowment, environment,
resource constraints and organizational desirability.
 We analyse whether the system can be developed and
how to develop it.
 dimensions are:
1)Technical 2)Economic 3) Organizational

8. STEPS OF FEASIBILITY STUDY
1)Define the objectives of feasibility study
2)Study the current environment
3)Analyse information requirements
4)Generation of alternative solutions
5)Report preparation

9. INFORMATION ANALYSIS
 System is analysed from a logical perspective.
 System is defined in broader terms and is segregated
in a hierarchy of black boxes.
 Each black box is a module with a specific role.
 The logical design is discussed with management and
after suitable changes, physical design is developed.
 Data stores and processes are designed and integrated
with the system.

10. INFORMATION ANALYSIS(cont..)
 A complete logical view of the system which fulfils all
requirements, is prepared in this stage.
 Comprehensive project plan is prepared which
includes activity-wise time schedule for system
development, manpower requirements, budget,
training requirements, testing plans, resource plans,
installation plans, organizational plans, document
plans.

11. SYSTEM DESIGN
 Logical design is detailed and a physical design
document is prepared.
 This document contains all implementation details of
the system.
 In this stage the entire system is put it on paper and
explained in diagrammatic terms.

12. SYSTEM CONSTRUCTION PHASE
 Two –step phase:
1)Application programme development
2)Procedures to interact with the system.
 In the first step, design document is studied and an
application programme developed.
 This step requires maximum manpower and resources.

13. APPLICATION PROGRAMMING
 Software that is the major part of the system is
developed.
 Lines Of Code(LOC) are written in a computer
programming language under a software environment
to create software system.
 Construction Cost Model(COCOMO) is used to
estimate project time and cost.
 Programming can be done using top-down or bottom-
up approach.

14. STEPS IN APPLICATION
PROGRAMMING
1)Designing the database and creating database
structures
2)Designing and developing the user interface
3)Programming to create functions
4)Connecting the database to application
5)Incorporating the business logic into software

15. PROCEDURE DEVELOPEMENT
 User’s interaction with the system is laid down.
 Different levels of users have different levels of access.
 Procedures will clearly stated in the form of operating
procedures and manuals.
 Key tasks are described in flow charts.

16. IMPLEMENTATION PHASE
 In this stage ,system is implemented at the
organization after coding and testing.
 Implementation tasks includes the following:
1)Planning for implementation
2)Communicating the implementation plan
3)Organizing MIS personnel
4)Selecting and procuring hardware

17. IMPLEMENTATION PHASE(cont..)
5)procuring the system software(OS)
6)Creating and deploying database
7)Training users
8)Creating and developing the physical infrastructure
9)Transiting to the new system

18. DEPLOYMENT
 Once new system has been tested and ready, new
system can be deployed using any of the 3 strategies:
1)Parallel strategy
2)Direct customer strategy
3)Phased approach

19. MAINTENANCE
 Three types of maintenance:
1)Corrective (to fix any bugs that are discovered)
2)Perfective (to improve system performance)
3)Adaptive (to adapt new technology)

20. SOFTWARE DEVELOPMENT LIFE
CYCLE(SWDLC)
 Subset of SDLC.
 SWDLC deals only with the application software
development life cycle of a system.
 Some popular software development methodologies
are :
1)Waterfall model
2)Prototype model
3)Rapid Application Development(RAD) model
4)Spiral model

21. WATERFALL MODEL
 Classic way of developing system.
 Systems are developed in phases and each phase is self
contained.
 Overlaps are not allowed.
 Development work flows from one phase to another in
a linear manner and progresses only when work on
preceding phase is complete.

22. PHASES OF WATERFALL MODEL
1)Requirement analysis phase
o Fact finding techniques(interview, questionnaire)
2)Design
3)Implementation
4)Testing
5)Deployment
6)Maintenance

23. WATERFALL MODEL

24. ADVANTAGES OF WATERFALL
MODEL
 Detailed early analysis cause huge advantages at later
phases
 If a bug found earlier, it is much cheaper (and more
effective) to fix than bugs found in a later phase
 Requirement should be set before design starts
 Disciplined and well-structured approach
 Effective for stable software projects

25. LIMITATIONS OF WATERFALL
MODEL
 Underutilizes manpower(many team member stay
idle).
 Real-life software development rarely follows this
method.
 Changes are expensive.
 Need to finish every phase fully to start next phase.

26. PROTOTYPING MODEL
 Client is anxious to complete the project.
 Developer has to create the software based on general
set of objectives provided by the client.
 Model starts with requirement gathering.
 Developer and client meet to check if prototype of the
proposed system works.
 The client reviews the software and suggests
refinements, this results to an improved prototype.
 This process is repeated and with each iteration,
prototype matures into a functional software.

27. PROTOTYPING MODEL(cont..)
 Prototyping process is not suitable for mission-critical
projects.
 It may serve the organization well for small
application.
 The problem is that clients may insist that the software
be built based on early stages of the prototype.
 The developer, in an anxiety to complete, may use
inappropriate components in the prototype, thereby
affecting the long-term sustainability of the software.

28. SPIRAL MODEL
 Pioneered by bohem(1988), evolutionary in nature.
 Some features of both waterfall and prototyping is
used.
 Software is created in incremental versions.
 In the early versions, software is not stable with
iterations, software begins the take shape and form.
 Spiral starts with a plan, then prototype is prepared by
some software development.
 Based on client feedback iterations will repeat.
 Spiral moves from one iteration to another, and after
each iteration software improves.

29. SPIRAL MODEL

30. THANK YOU..