Sdlc 694314

System Development Life Cycle (SDLC)

Seminar Topics System Concepts  Information Concepts  Decision System  Organization and MIS  SAP  Case Studies on ◦ Effect of MIS on Business ◦ Use of Wireless technologies in business ◦ Use of Internet technology in business ◦ Artificial Intelligence and Expert Systems ◦ Business Development Process (Ex of SDLC) 

What is SYSTEM DEVELOPMENT ? “System Development” refers to the process of – 

Examining a business situation with the intent of improving it, through better procedures and methods.

System Development is having two major component in it 

System Analysis – Analysis of current system for Problems & Demerits in it and Additional requirements in new system



System Design – Process of planning new system which will replace the old one

Why System Development 

New design idea to smoothen the process in the organization.



Evolving environmental changes such as Competition.



Adding new business or product line to present business.



Present system does not satisfy the s information needs.



Present system no longer efficiently and effectively meets the Goals of organization.



Excessive time spent in correcting errors.



Current Reports / Outputs not meting s decision making skills.



Escalating customer and vendor complaints.

System Development “Methodology” A system development methodology is a formalized, standardized, documented set of activities used to manage a system development project. It can be characterized as follows: 

DIVISION OF PROJECT into the identifiable phases which can be managed without having any problem.



REVIEW OF DEVELOPMENT PROCESS by TOP Management on periodically by getting deliverables.



APPROVALS from all the participants of the Development (i.e. s, Managers, Analyst and Auditors).



TESTING OF SYSTEM thoroughly prior to implementation to ensure that it meets ’s needs.



TRANNING of who will operate the new system.



POST IMPLEMENTATION REVIEW for effectiveness and efficiency of new system

Steps of System Development 

System Investigation ◦ Conduct of Product feasibility ◦ Development of project management plan



System Analysis ◦ Analyze the information needs of all stakeholders in a business ◦ Development of functional requirements ◦ Development of Logical Models of existing system



System Design ◦ Development of specifications ◦ Development logical modes of new system



System Implementation ◦ Develop S/W, Acquire H/W, Testing the system, Training, Convert

SDLC Phases Preliminary Investigation

System Analysis

System Operation & Maintenance

System Implementation n

System Design

System Development

Six Phases of the System Development Life Cycle Preliminary Investigation ◦ Assesses feasibility and practicality of system  System Analysis ◦ Study old system and identify new requirements ◦ Defines system from 's view  System Design ◦ Design new/alternative system ◦ Defines system from technical view 

Six Phases of the System Development Life Cycle 

System Development ◦ New hardware and software is acquired, developed, and tested



System Implementation ◦ System installation and training



System Operation & Maintenance ◦ Daily operation ◦ Periodic evaluation and updating

Who participates in the system development life cycle?

Systems Analyst

A person responsible for deg and developing information system He is the Liaison between s and IT professionals

Phase 1: Preliminary Investigation / Feasibility Study 

The objective of this phase is to review all requests and identify those proposals that are most beneficial to the organization.



Three primary tasks: ◦ Define the problem  By observation and interview, determine what information is needed by whom, when, where and why

◦ Suggest alternative solutions ◦ Prepare a short report

Phase 1 Cntd… Preliminary Investigation object can be achieved in following steps: 

Request Clarification



Feasibility study



Estimating Costs and Benefits



Request Approvals

Request Clarification Defining the Scope and Objective of Request:



◦

An analyst has to define for which objective a request for development is submitted.

Conducting the Investigation



◦

This is nothing but the Collection of data / inputs by: 

Reviewing internal documents (i.e Organizational Charts, operating procedures etc.



Conducting interviews of , Supervisory Personal and Managers



Questionnaire



t-Application Design (JAD) session



Research

Feasibility Study Evaluation of alternative systems through cost and benefit analysis:

Measure of how suitable system development will be to the company

Technical feasibility

Economic feasibility (also called cost/benefit feasibility)

Four feasibility tests:

Legal feasibility

Schedule feasibility

Operational feasibility

Feasibility (Possibility) Study Technical Feasibility: Hardware and software availability, Technical Guarantee of Accuracy, Reliability, Easy to Access, Data security, technical capacity to hold data and future expansion.  Economical Feasibility: Evaluation of cost & Benefits expected.  Benefits- Cost Savings, Increased Revenue, Decreased Investment 

•

• •

Feasibility (Possibility) Study

• • • •

Operational Feasibility: Finding the possibilities on How well the proposed system s the business priorities of the organization. How well the proposed system will solve the identified problem How well the proposed system will fit with existing system

Finding views of workers, employees, customers & suppliers about the use of new system.

Schedule Feasibility: Estimation of time to take for new system to become operational. Legal feasibility: Testing whether new system will comply the patent, copyright and licensing policies of company, Government etc.

Estimating Cost & Benefit COSTS: Development Costs: This includes cost of testing, training, start up costs, salary to designers, acquisition cost of hardware & software. Operation Costs: This includes operator salary, maintenance costs, etc. Intangible Costs: Loss of employee productivity, self confidence etc. BENEFITS: Tangible Benefits:  Increase in sales / Contribution / Profits  Decrease in investment, operating and processing cost.  Improved information availability, analysis, Management Decision skill Intangible Benefits:

• • • •

•



• • • •

Phase 2: Collection of data and facts Analysis of Present System System Analysis of Proposed system Analysis Every system is built to meets some set of needs and to assess these needs, the analyst often interact extensively with the people, who will be benefited from the system In order to determine the requirement of those peoples he can use following facts finding techniques: Documents: This includes the Manuals, diagrams, forms, organizational charts etc. It should be ensured that all documents are accurate & up to date Questionnaires: These are skillfully drafted group of standard question which can be given to all personal and can be analyze quickly. Interviews: To get a complete picture of problems and opportunities. Observation: Surprise Visit of s work palace to get a clear picture of ’s environment.

Phase 2: System Analysis Tools Used 

Checklists - list of questions



Top-down analysis - start with top level components, break down into smaller parts through each successive level



Grid charts - to show relationship between inputs and outputs



System flowcharts - charts flow of input data, processing, and output which show system elements and interactions

Phase 2: System Analysis Documentation Procedure 

Complete description of current system and its problems



Requirements for new system including: ◦ Subject ◦ Scope ◦ Objectives ◦ Benefits



Possible development schedule

Phase 3: System Design 

In depth study of the existing system to determine what the new system should do. ◦ Expand on data gathered in Phase 1, examine: ◦ Formal lines of authority (organization chart)



In addition to observation and interviews



◦ Standard operating procedures ◦ How information flows Reasons for any inefficiencies



Uses specifications from the systems analysis to design alternative systems



Evaluate alternatives based upon: ◦ Economic feasibility - Do benefits justify costs? ◦ Technical feasibility - Is reliable technology and training available? ◦ Operational feasibility - Will the managers and s it?

Phase 3: System Design Tools Used 



Computer-Aided Software Engineering (CASE) tools are software-based products designed to help automate the production of information systems. Examples: ◦ ◦ ◦ ◦ ◦ ◦

Diagramming Tools Data Repositories Prototyping Tools Test Data Generators Documentation Tools Project Management Tools

Phase 3: System Design Documentation Produced 

System Design Report ◦ Describe Alternatives including:  Inputs/Outputs  Processing  Storage and Backup

◦ Recommend Top Alternative based upon:  System Fit into the Organization  Flexibility for the future  Costs vs. benefits

Phase 4: System Development 

Build the system to the design specifications ◦ Develop the software  Purchase off-the-shelf software OR  Write custom software

◦ Acquire the hardware ◦ Test the new system  Module (unit) test - tests each part of system  Integration testing - tests system as one unit

◦ Create manuals for s and operators

Phase 5: System Implementation 

Convert from old system to new system



Train s



Compile final documentation



Evaluate the new system

Phase 5: System Implementation Types of Conversion 

Direct/plunge/crash approach – entire new system completely replaces entire old system, in one step



Parallel approach - both systems are operated side by side until the new system proves itself



Pilot approach - launched new system for only one group within the business -- once new system is operating smoothly, implementation goes companywide



Phased/incremental approach - individual parts of new system are gradually phased-in over time, using either crash or parallel for each piece.

Phase 5: System Implementation 

Training ◦ Ease into system, make them comfortable, and gain their ◦ Most commonly overlooked ◦ Can be commenced before equipment delivery ◦ Outside trainers sometimes used

Phase 6: Operations & Maintenance 

Types of changes: ◦ Physical repair of the system ◦ Correction of new bugs found (corrective) ◦ System adjustments to environmental changes ◦ Adjustments for s’ changing needs (adaptive) ◦ Changes to better techniques when they become available (perfective)

Phase 6: Operations & Maintenance 

Evaluation Methods ◦ Systems audit - performance compared to original specifications ◦ Periodic evaluation - “checkups” from time to time, modifications if necessary

Deliverables of the SDLC Approved Feasibility Study

Preliminary Investigation System Analysis

System Design

Problem Specifications

Design Specifications System Development

Begin building new system

Abort Project Goto next phase Goto Previous phase

Coded and Tested System

System Implementation

System converted s trained

System Maintenance Operational System Documentation completed

MIS Syllabus Management Information Systems











1. Information Systems: data vs Information, Strategic role of information in management, Organization as an information system. TPS, MIS, DSS, ESS, OAS, Networking concepts, telecommunications networks. 2. Systems Development: the concept of systems development life cycle (SDLC),Types of SDLC, Use of flow charts. . Application Technologies: ERP concepts, Evolution of ERP, ERP packages, SAP, Baan, MFG-PRO, Oracle, ERP Evaluation, ERP and BPR, ERP Implementation, Extended ERP, Case studies. 4. Web Publishing: web publishing, Types of websites, Web surfing, E-commerce, B2B, B2C, C2C, E-commerce security issues, Ethical issues 5. Practicals on ERP -. Functional modules in business.