Systems Analysis and Design 5th Edition Chapter 3 PDF

Systems Analysis and Design 5th Edition Chapter 3. Requirements Determination Roberta Roth, Alan Dennis, and Barbara Haley Wixom System Analysis and Design System Analysis and Design 2 System Analysis and De...

Systems Analysis and Design 5th Edition Chapter 3. Requirements Determination Roberta Roth, Alan Dennis, and Barbara Haley Wixom System Analysis and Design System Analysis and Design 2 System Analysis and Design 3 System Analysis and Design 4  Chapter 3 Outline The analysis phase. Requirement determination. Requirement elicitation techniques. System Analysis and Design 5  Analysis apply requirement analysis techniques (business process automation, business process improvement, business process reengineering).(‫)تحديد سبب الحاجه للنظام الجديد‬ Use requirement gathering techniques (interview, JAD session, questionnaire, document analysis, or observation). Develop requirement definition. System Analysis and Design 6  The Analysis Phase The System Development Life Cycle (SDLC) is the process by which the organization moves from the current system (as-is system) to the new system (to-be system). In many ways, the requirement definition is the single most critical step of the entire SDLC. Analysis refers to breaking a whole into its parts with the intent of understanding the parts’ nature, functions, and interrelationships. The planning phase deliverables are the key inputs into the analysis phase. System Analysis and Design 7  The Analysis Phase(cont’d) The basic process of analysis involves three steps: - Understand the existing situation (the as-is system) - Identify improvements - Define the requirement for the new system (the to-be system) System Analysis and Design 8 The Analysis Phase(cont’d) The final deliverables of the analysis phase is the system proposal. At the conclusion of the system analysis, the system proposal is presented to the approval committee The line between analysis and design is very blurry, because the deliverables created in the analysis phase are the first step in the design phase of the new system. System Analysis and Design 9 Requirements Determination In many ways, determining requirements is the single most critical aspect of the entire SDLC. Although many factors contribute to the failure of systems development projects, failing to the determine the correct requirement is a primary cause. If the requirements are later found to be incorrect or incomplete, significant rework may be needed, adding substantial time and cost to the project. System Analysis and Design 10  Requirements Determination Requirements determination is performed to transform the system request’s high- level statement of business requirements into a more detailed, precise list of what the new system must do(Functions, Processes, Applications..etc) to provide the needed value(Automation, Improvement, Benefits) to the business. System Analysis and Design 11  What is a Requirement? A requirement is a statement of what the system must do or what characteristics it needs to have. Requirements describe: - what the business needs (business requirements) - what the users need to do (user requirements) - what the software should do (functional requirements) - characteristics the system should have (non-functional requirements), and - how the system should be built (system requirements) System Analysis and Design 12 What Is a Requirement? Requirement in design phase are written from the developers perspective, and they usually are called system requirement. Those requirements will change over time in the design and implementation phases. Functional requirement(FR) related directly to a process that the system has to perform or information it needs to contains. Non-functional requirement(NFR) refer to behavioral properties that the system must have. System Analysis and Design 13  Functional requirement Functional Description Examples requirement Process-oriented A process the system The system must allow registered must perform; a process customers to review their own the system must do order history for the past three years. The system must check incoming customer orders for inventory availability. The system must change customer status to ‘inactive’ after three years of inactivity. Information-oriented Information the system The system must retain customer must contain order history for three years. The system must include real-time inventory levels at all warehouses. The system must include budgeted and actual sales and expense amounts for current year and three previous years. System Analysis and Design 14  Non-Functional Requirement Nonfunctional Description Examples Requirement Operational The physical and The system can run on handheld technical environments devices. in which the system will The system should be able to integrate operate with the existing inventory system. The system should be able to work on any Web browser. Performance The speed, capacity, and Any interaction between the user and reliability of the system the system should not exceed 2 seconds. The system downloads new status parameters within 5 minutes of a change. The system should be available for use 24 hours per day, 365 days per year. The system supports 300 simultaneous users from 9–11 A.M.;150 simultaneous users at all other times. System Analysis and Design 15 Non-Functional Requirement(cont’d) Nonfunctional Description Examples Requirement Security Who has authorized Only direct managers can see personnel records of staff. access to the system Customers can see their under what circumstances order history only during business hours. The system includes all available safeguards from viruses, worms, Trojan horses, etc. Cultural and Political Cultural and political The system should be able to distinguish between U.S. factors and legal currency and currency from requirements that affect other nations. the system Company policy is to buy computers only from Dell. Country managers are permitted to authorize custom user interfaces within their units. Personal information is protected in compliance with the Data Protection Act. System Analysis and Design 16 The Process of Determining Requirements Both business and IT perspectives are needed to determine requirements during the analysis phase. The most effective approach is to have both businesspeople and analysts working together to determine requirements. The analyst must also consider how best to elicit the requirements from the stakeholders. The process of determining requirements continues throughout the analysis phase, and the requirements definition evolves over time. System Analysis and Design 17 Requirements Elicitation Techniques Requirements Elicitation in Practice The analyst should recognize that important side effects of the process of determining requirements include building political support for the project and establishing trust between the project team and the users. The analyst should carefully determine who is included in the process of determining requirements. System Analysis and Design 18 Requirements Elicitation Techniques There are different requirements gathering techniques: 1.interviews. 2.JAD sessions. 3.questionnaires. 4.Document analysis 5.Observation System Analysis and Design 19  1. Interviews Is the most commonly used technique, can be one to one or a group of users are interviewed all together because of time constraints. There are five steps for any interview: ◼ Selecting Interviewees ◼ Designing Interview Questions ◼ Preparing for the Interview ◼ Conducting the Interview ◼ Post-Interview Follow-up System Analysis and Design 20  1.1 Selecting interviewees Including people at different levels of the organization ◼ Managers, Users, staff, business device technicians ◼ Administrative and financial authority ◼ Other key stakeholders System Analysis and Design 21 1.2 Designing interview questions System Analysis and Design 22  1.3 Preparing for the interview Prepare a general interview plan ◼ List of question ◼ Anticipated answers and follow-up Confirm areas of knowledge Set priorities in case of time shortage Prepare the interviewee ◼ Schedule ◼ Inform of reason for interview ◼ Inform of areas of discussion System Analysis and Design 23  Cont’d Sample of Interview schedule System Analysis and Design 24  1.4 Conducting the interview Appear to be professional and unbiased. Record all information. Be sure you understand the issues that are discussed. Separate facts from opinions. Give interviewee time to ask questions, and brief explain what will happen next. Interpersonal Skills Analysts should enhance their interpersonal skills to improve their interviewing success System Analysis and Design 25 1.5 Post-interview follow-up After the interview, the analysts needs to prepare an interview report p.g 119. The report includes interview notes. The report is sent to interviewee with a request to read it and inform the analyst of clarification and updates. Look for gaps and new questions. System Analysis and Design 26 2. Joint Application Development (JAD) JAD is an information gathering technique that allows the project team, users, and management to work together to identify requirements for the system. It can reduce scope creep by 50%, JAD is a structure process in which 10 to 20 users meet under the direction of a facilitator skilled in JAD techniques. System Analysis and Design 27  2.1 Selecting JAD participants Selecting JAD participants in the same basic way as selecting interview participants. Facilitator ◼ Expert in JAD and e-JAD techniques ◼ In many cases, the JAD facilitator is a consultant external to the organization. System Analysis and Design 28 2.2 Designing and Preparing for the JAD sessions JAD sessions can run from a half day to several weeks depending upon the size and scope of the project. JAD success depends upon a careful plan. Most JAD sessions are designed to collect specific information from users. It is important to prepare the analyst and participants for the JAD session. System Analysis and Design 29 2.3 Conducting the JAD session Most JAD sessions follow formal agenda and ground rules. The JAD facilitator performs three key functions: ◼ Keep session on track, following the agenda. ◼ Help the group understand the technical terms and terminology. ◼ Record group’s input on a public display area. The facilitator must remain neutral at all time and help the group through the process. System Analysis and Design 30  2.4 Post JAD follow-up Post-session report is prepared and circulated among session attendees The report should be completed approximately a week to two after the JAD session System Analysis and Design 31 JAD Meeting Room System Analysis and Design 32  3. Questionnaires A questionnaire is a set of written questions for obtaining information from individuals. Selecting participants - using a sample of people who are representative of the entire group. Designing the questionnaire – following good practice guidelines. Administering the questionnaire – improving the response rates. Questionnaire follow-up – developing a report. System Analysis and Design 33 Questionnaires(cont’d) Good questionnaire design System Analysis and Design 34  4. Document Analysis Document analysis is used to understand the as-is system. Forms, reports, policy manuals, organization charts describe the formal system that the organization uses. The “real” or informal system differs from the formal one and reveals what needs to be changed. The indication that system needs to be changed is when users create new forms or make changes to the existing forms/reports. System Analysis and Design 35  5. Observation Observation – the act of watching processes being performed. It is a powerful tool to gain insight into the as- is system, and to check the validity of information gathered from other sources. Nonetheless, people tend to be extremely careful in their behaviors when they are being watched. System Analysis and Design 36  SUMMARY Analysis focuses on capturing the business requirements for the system Requirement Determination is the part of analysis in which the project team turns the business requirements stated in the system request into a precise list of requirements. Five Requirements Elicitation Techniques can be used to elicit business requirements. System Analysis and Design 37 Sample Requirements Definition System Analysis and Design 38 Functional Requirements 1. New Vehicle Management 1.1 The system will allow managers to view the current new vehicle inventory. 1.2 The system will allow the new vehicle manager to place orders for new vehicles. 1.3 The system will record the addition of new vehicles to inventory when they are received from the manufacturers. 2. Vehicle Sales Management 2.1 The system will enable salespersons to create a customer offer. 2.2 The system will allow salespeople to know whether an offer is pending on a specific vehicle. 2.3 The system will enable managers to record approval of a customer offer. 2.4 The system will prepare a sales contract. 2.5 The system will prepare a shop work order based on customer requested dealer options. 2.6 The system will record a customer deposit. 2.7 The system will record a customer payment. 2.8 The system will create a record of the customer's vehicle purchase. 3. Used Vehicle Management 3.1 The system will record information on a customer trade-in vehicle... etc. System Analysis and Design 39 Nonfunctional Requirements 1. Operational 1.1 The system should run on tablet PCs to be used by salespeople. 1.2 The system should interface with the shop management system. 1.3 The system should connect to printers wirelessly. 2. Performance 2.1 The system should support a sales staff of 15 salespeople. 2.2 The system should be updated with pending offers on vehicles every 15 minutes. 3. Security 3.1 No salesperson can access any other salesperson's customer contacts. 3.2 Only the owner and sales manager may approve customer offers. 3.3 Use of each tablet PC should be restricted to the salesperson to whom it is assigned. 4. Cultural and Political 4.1 Company policy says that all computer equipment is purchased from Dell. 4.2 Customer personal information is protected in compliance System Analysis and Design 40