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LECTURE 7

CHAPTER 6. LECTURE 7. Information Systems Department. 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.

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LECTURE 7

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  1. CHAPTER 6 LECTURE 7 Information Systems Department

  2. 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

  3. Beginning of a System Development System Development usually begins when a problem or opportunity is identified by Managers, it can be because of any of the followings: • 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 users 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 users decision making skills. • Escalating customer and vendor complaints.

  4. 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. Users, Managers, Analyst and Auditors). • TESTING OF SYSTEM thoroughly prior to implementation to ensure that it meets user’s needs. • TRANNING of user who will operate the new system. • POST IMPLEMENTATION REVIEW for effectiveness and efficiency of new system

  5. System Development Life Cycle (SDLC) • How are Information Systems purchased or built? • The process which includes analyzing the system requirements to designing and implementing a new system is called the System Development Life Cycle (SDLC).

  6. System Development Life Cycle (SDLC) • SDLC is an organized set of activities that guides those involved through the design, development, and implementation of an information system. • The number and names of each SDLC phase may vary by author and software company, but they all are very similar. • The participants include technical staff, but also include non-technical business experts including end-users.

  7. System Development Life Cycle In an organization System Development Object can be achieved by following steps: • Preliminary Investigation • Requirements analysis or system analysis • Design of System • Development of System • Implementation and Maintenance

  8. Ongoing Activities • Project Management • Feasibility Assessment • Documentation • Information Gathering. Systems Development Life Cycle

  9. 1. Preliminary Investigation • A brief study of the problem to determine whether the project should be pursued. • Usually launched by a formal project request. • Define the Problem. • Set scope (boundaries) of the problem. • Feasibility - measure of how suitable the development of a system will be to the organization. Preliminary Investigation object can be achieved in following steps: • Request Clarification. • Feasibility study. • Estimating Costs and Benefits. • Request Approvals.

  10. 1. Preliminary Investigation Request Clarification • Defining the Scope and Objective of Request: • As mentioned in the objectives of System development objective earlier, 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 User, Supervisory Personal and Managers • Identify viable option: • Analyst has to identify the viable option by applying his common sense and intuitions on his investigation

  11. 1. Preliminary Investigation Feasibility (Possibility) Study Evaluation of alternative systems through cost and benefit analysis: • 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. • Operational Feasibility: Finding views of workers, employees, customers & suppliers about the use of new system. • Schedule Feasibility: Estimation of time to take new system to become operational. • Legal feasibility: Testing whether new system will comply financial reporting requirements & Company’s contractual obligations.

  12. 1. Preliminary Investigation Feasibility Assessment Report • Introduction – brief statement • Existing System • Background • Problems • Benefits of a New System • Feasibility of a New System • Operational • Schedule • Technical • Economic • Recommendation

  13. 1. Preliminary Investigation 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: • Increase in Goodwill / Improved Image of Business

  14. 1. Preliminary Investigation Request Approval Based on the Observation and Findings of the Analyst, selected requests are put up for the approval of management

  15. 2. Requirement Analysis and System Analysis After the selection of a request for development analyst study in depththe Present and Proposed New System. This is the study of weakness & Problems in the present system and management requirements of new system. This phase of System Development is being completed in following step: • Collection of data and facts • Analysis of Present System • Analysis of Proposed system

  16. 2. Requirement Analysis and System Analysis Collection of Data & Facts 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 users work palace to get a clear picture of user’s environment.

  17. 2. Requirement Analysis and System Analysis Analysis of Present System Detailed investigation of the present system involves collecting, organizing and evaluating facts about the present system and the environment in which it operates by studying following areas in depth: • Review of Historical Aspects of organization • Analyze Present inputs to the system • Review of all data file maintained irrespective of online or offline • Review methods, procedures & data communications • Analyze Present outputs of system • Review internal controls • Model the existing physical system and logical system • Undertake overall analysis of present system

  18. 2. Requirement Analysis and System Analysis Analysis of Proposed System After each functional area of present system is defined the purposed system specification must be defined. These specification will be based on the strength and weakness of present system. System Specification which should be in conformity with the Project Objective and Areas Covered should be following: • Output / Reports • Maintenance of Database • Data Inputting Process • Methods and Procedures to show the relationship between Input and Output • Work volume including peak period work volume

  19. 3. System Design Build or Buy? • Build Software • Customized • Developed in-house • Developed by outside vendor • Prototyping – limited function if any; shows what system may look like. • Will be proceeding to Phase 4: Development • Buy Software • Prepackaged software • Select software vendor • Customization may be offered by software vendor for a price • Will be proceeding to Phase 4: Testing

  20. 3. System Design System design first involves Logical Design. First one has to write detailed specification that called design specification. Than secondly it involves Physical Design. This Phase of System Development includes following functions: • Designing System Output • Designing System Input • Data Storage

  21. 3. System Design Designing System Output • Important factor of Output Design: A process of Output designing contained Designing of Content (required info in an output), Form (the way in which a content presented to user), Volume (quantum of Output i.e. Prints), Time Lines (time of need of outputs), Media (method of output i.e. Print, CD etc) and Format (Physical arrangement of Data). • Way of Presenting Information: The way in which data will be presented to the User which should be simple and better understandable . • Design / Layout of Output: The layout of a output can be in Printed form, visual on screen etc.

  22. 3. System Design Designing of System Input • Important Factor of Input Design: A process of Input designing contained Designing of Content (required info in input), Form (the media in which input is received by user), Volume (quantum of input records), Time Lines (required time to enter one record), Media (method of input i.e. keyboard, etc) and Format (Input by the user in the system). • Coding: To reduce input control errors and speed up the entire process coding is very important. This is also important to get all records in a specific form. • Methods: Individually (Unique codes giving only one option to user out of may i.e selection of gender from male or Female etc), Space or suggestive (for brief information), • Schemes: Classification Codes (only single digit is required for quick input the ), Function code (activities to be performed without spelling out all details) etc.

  23. 3. System Design Data Storage This includes the storage of data, indexing etc. For storage of data it can follow following approaches: • Conventional File Approach: This is a traditional approach where each transaction is updated in the master file, each application have their own database and it is not useful for other applications. • Database Approach: This support decision making skill of the management. Data are stored in the small-small database files and same data can be used in the multiple applications. (Files maintained as a process of the organization for MIS etc.)

  24. 4. System Acquisition & Development • Project Management (Scheduling) • Define tasks and schedule • Use project management software to plan human resources and dependencies (see next slide). • Required resources • Testing • Use various tests to evaluate entire system(Testing slide coming up…)

  25. 4. System Acquisition & Development Project Management • The process of planning, scheduling, and controlling activities • Set scope (goal, objectives, expectations) • Activities and Deliverables to be completed • The order activities occur (some activities are concurrent and others are dependent) • Time and cost estimates Gantt Chart

  26. 4. System Acquisition & Development Required resources After designing the system all required resources (hardware & Software) should be gathered. If some of them are already with the organization than it reduces the cost of acquisition, for remaining items organization has to plan its procurements process, this includes following: • Selection of Hardware: • Selection of Software • Vendor Selection

  27. 4. System Acquisition & Development Selection of Hardware While selecting the hardware for new system a developer must keep in mind following: • Latest Technology • Whether requirement of business is for Scientific or Business Computer • Software supplied by the manufacture and requirement of additional software • Compatible with the existing systems in organization

  28. 4. System Acquisition & Development Selection of Software Selection of a perfect Software for organization is totally depends on the followings: • Rapid Implementation: Whether software can be implemented quickly and put on use ASAP. This characteristic will not be there if software is to be developed, hence that will take long time. • Low Risk of Quality: Software should be properly tested by the manufacturer for the quality otherwise organization has to spend its precious time on quality assurance. • Low Risk of Cost: The cost and benefit analysis will give us the perfect cost, which organization can bear for acquiring the given software.

  29. 4. System Acquisition & Development Vendor Selection This is finding of resources from new system hardware and software will be procured. At resource will be finalized based on the following: • Performance Capability in relation to cost and quality: • Cost & Benefits: Preparation of comparative statements based on the quotations received from vendors with terms and conditions. • Maintainability: Maintenance requirements of the new equipments • Compatibility with the Existing system: • Vendor support: Post sale support from vendors

  30. 4. System Acquisition & Development System Testing This is Performing Parallel Operation and get the following done to analyze the operational implementation feasibility: • Preparation realistic data based on the actual working data of the organization. It may be based on the Historical data of the organization. • Processing of Test Data with the new system and take all outputs which can be possible. • Checking result of all system with the results of the same data in the current system for the accuracy and error in the processing. • Review result with future users, operational and support personal.

  31. 5. Implementation & Maintenance As the final Phase of the System Development it gives the results of the whole process and handover the new system to end users. This also includes the overall review of the development process for its leakages and errors in it. To complete this phase a developer has to complete the following functions successfully: • Equipment Installation. • Training Personnel. • Conversion Procedure. • Post Implementation Evaluation (Feedback).

  32. 5. Implementation & Maintenance Equipment Installation This includes following functions: • Site Preparation: Preparing the site for installation and mobilizing all required equipments and personnel at the site. • Equipment Installation: Assembling and commissioning of the equipments (hardware) and installation of software • Equipment Checkout: Organize test runs of the system with sample actual data and thereafter if it performs satisfactory than with the live actual data.

  33. 5. Implementation & Maintenance Training Personnel Since user are not familiar with the New System, System Development Process includes training of - • System Operators: IT personnel who will handle the system maintenance in the future. • Users (Operators): The final user who will work on the system. If there are deficiencies in Training, thesemay translate into reduction in user Productivity Levels

  34. 5. Implementation & Maintenance Conversion Procedures This is the time when organization switch over from old system to new developed system. Following are the Strategies / Methods for conversion / Changeover of old system to new system. • Direct Changeover: Direct closing the old system and starting the new one. • Parallel Changeover: for sometime operating both system simultaneously. • Gradual Changeover: Department wise switch over to new systems. • Distributed Changeover: Any other method which management feels good for organization.

  35. 5. Implementation & Maintenance Conversion Procedures

  36. 5. Implementation & Maintenance Post Implementation Evaluation (Feedback) • Analysis of Satisfaction of Users or checking whether system is Operating Properly or whether Objectives of System Development is achieved or not, is the most important function in whole System Development process. • This is also important for development of new system in future since each development gives some experiences and lists some things to be taken care off.

  37. 5. Implementation & Maintenance Post Implementation Evaluation (Feedback) Post Implementation Evaluation includes following area: • Development Evaluation: Check whether development was done within schedule and budgets. • Operation Evaluation: Check whether system is capable for handling the duties and objective of development is achieved. • Information Evaluation: Check Satisfaction of users etc.

  38. Any Questions ?

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