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					SYSTEM ANALYSIS AND DESIGN
                   SYSTEM
   A system is an orderly grouping of
    interdependent component linked together
    according to a plan to achieve a specific
    purpose.

   OPEN SYSTEM-An open system has
    many interfaces with its environment.

   CLOSED SYSTEM-A Closed system has no
    interaction with the outside world.
         CHARACTERISTICS OF A SYSTEM

   Organization-is the an arrangement of components
    that help to achieve objectives.
   Interaction-refers to how each component in a system
    are connected together.
   Interdependence-means that parts of organization
    depend on one another.
   Integration-is concerned with how systems are tied
    together.
   Central objective -A common goal of all systems and
    its subsystems are called central objective.
      SYSTEMS IN DAY TO DAY LIFE

   Educational system
   Telephone system
   Inventory control system
   Payroll management system
   Office administration system
   Transportation system
   Business system
   Computer system
System, Elements and Basic Goal (Eg)
SYSTEM       ELEMENTS                 Basic Goal
Factory      People, machines,        Production of goods
             buildings, material
Police       People, equipment,       Control of crime
             buildings,
             communication
             networks
Computer     Physical components      Processing of data
             and connections
Philosophy   Ideas                    Understandings
Accounting   Journals, ledgers,       Report of Financial
             computers, people        operations
Business     Marketing, Production,   Maximum profit
             Accounting
             SYSTEM ANALYSIS
   System Analysis is an activity that takes
    place when new information systems are
    being developed or existing systems are
    being changed.

   The various tools used in system analysis
    are: Data Flow Diagram (DFD), Data
    dictionary, Structured English (pseudo code),
    Decision table, Decision Tree.
                    SYSTEM DESIGN
     System Design involves designing a new
      system that will meet the requirements
      identified during system analysis.
     OBJECTIVES OF SYSTEM DESIGN
1.    Efficiency
2.    Cost
3.    Flexibility
4.    Simplicity
5.    Reliability
6.    Security
     PURPOSE OF SYSTEM DESIGN
   Specifying how output is to be produced and
    on what format (Output design)
   Designing the input data and files
   Designing the different forms
   Designing the procedures for constructing
    and testing the program
              SYSTEM ANALYST
   A system analyst is a person who is
    responsible for the analysis, design and
    implementation of a business system on the
    computer.
   Qualities of a System Analyst
       1. Communication skills
       2.Problem solving skills
       3.Business knowledge
       4.Technical knowledge
ELEMENT (OR COMPONENTS) OF A SYSTEM
 To reconstruct a system, the following key elements must be considered:
  1. Inputs-involves capturing and assembling elements that enter the system
 to be processed.

   2. Processor (s)-is the element of a system that involves the actual
 transformation of input into output

 3. Outputs-A major objective of a system is to produce an output that has
 value to its user

 4. Control-The control element guides the system.

 5. Feedback-Control in a dynamic system is achieved by
      feedback

 6. Environment-is the “super system” within which an organization
 operates.

 7. Boundaries and Interface-A system should be defined by its
 boundaries-the limits that identify its components, processes, and
 interrelationships when it interfaces with another system.
SYSTEM DEVELOPMENT LIFE CYCLE(SDLC)

   System Development lifecycle is a set of activities
    used for developing a new system or changing the
    existing system.
   The idea of creating a new system originates in the
    environment or from within the organization.
   The following two categories are suggest an idea for
    developing a new system
                     1. Organization based
                     2. Environment based
DIFFERENT STAGES OF SYSTEM
DEVELOPMENT LIFE CYCLE
1.   Recognition of need or Preliminary
     study/survey
2.   Feasibility study
3.   Analysis of the present system
4.   Design of a candidate system
5.   Development and Testing
6.   Implementation
7.   Post implementation, maintenance and
     review
1.Recognition of need (Preliminary Survey)
       It aims to conduct a background study of the existing
        system.
                            OBJECTIVES
         To determine whether the new system is feasible or not.
         To set the objectives, scope and limitations of the system.
         To establish a good relationship between the users of the
          system and the persons working in the data processing
          department.
         To estimate the resources for the development and maintenance
          of the system.
         To identify the benefits of the new system.
          2.FEASIBILITY STUDY
 A feasibility study is a test of a system proposal
  according to its workability, impact on the organization,
  ability to meet user needs, and effective use of
  resources.
 It focus on three major questions:

1.What are the user’s needs and how does a system meet
  them?
2.What are the resources available for proposed system?
3.What is the likely impact of the new system on the
  organization?
 The result of feasibility is a formal proposal. ie after
  feasibility study a report is submitted to the
  management, this report is called feasibility report.
               Feasibility report
1.Statement of the problem

2.Summary of findings and recommendations

3.Details of findings

4.Recommendations and conclusions
3.ANALYSIS OF PRESENT SYSTEM
    Analysis is a detailed study of the various operations
    performed by a system. This involves gathering
    information and using structured tools for analysis.

   Analysis involves the following two process
     1. Detailed evaluation of present system
      2. Data collection
                    4.DESIGN
   System design involves designing a new system
    that will meet the requirements identified during
    system analysis.

   The system design also describes the data to be
    input, calculated or stored.

   Design involves the following,
             1.General design
             2.Input/Output design
             3.File design
       5.Development and Testing
   After the design stage, development of
    software will be started
   Programmers are responsible for
    documenting the programs
   Document providing an explanation of how
    and why certain procedure are coded in
    specific way
   After creating a program, program testing is
    done
         6.IMPLEMENTATION

   Implementation is concerned with detail-the
    physical creation of the candidate system

   The key point is actual operation and user
    acceptance testing before the system is
    released to the user.
7. POST IMPLEMENTATION AND
    MAINTENANCE
   After implementation, maintenance begins
   This includes enhancements, modifications,
    or any change from original specifications
   This phase terminates the system
    development life cycle.
FACT FINDING TECHNIQUES

   The specific method analyst used for collecting data
    about requirement are called fact-finding technique

   The fact finding technique includes the following

1.Interview
2.Questionnaire
3.Onsite observation
4.Review of written documents
Thank you

				
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