Summary ICT2621_Exam Summarized Notes.

ICT2621_Exam Summarized Notes. Structured Systems Analysis And Design. System analysts use a process called business process modeling to represent company operations and info needs and requires a business profile and a series of models that document business processes. Business Profile is an overview of a company’s mission, functions, organization, products, services, customers, suppliers, competitors, constraints and future direction. Starting point of modeling process. Business Process is specific set of transactions, events, and results that can be described and documented. (BPM) Business Process Model graphically displays one or more business process. For complex operations computer-based modeling tools that use standard language (BPMN) Business process modeling notation is used (include various shapes and symbols) Internet-dependent firm – Amazon Brick-and-mortar – physical locations e-Commerce (electronic commerce) or I-Commerce (Internet commerce), 2 x Main Sectors: B2C (Business-to-Consumer) B2B (Business-to-Business) – used EDI (Electronic data interchange), enabling computer-to-computer data transfer, plan production etc based on another companies data. XML (Extensible markup language) offer std protocols, universal availability and low communication costs… allowing web-based communication between different hardware and software environments. Popular form of B2B interaction is called (SCM) Supply Chain Management or (SRM) Supplier relationship management. Enterprise Computing IS that support company-wide operations and data management requirements, referred to as (ERP) Enterprise resource planning. Transaction Processing (TP) Process data generated by day-to-day business operations. Series of tasks performed by processing a sales order: (processed as one group) - Verify Cus Data - Check Credit status - Post to AR - Check stock availability - Adjust Invent Data - Update Sales Activity File 4 Business Support Business Support Systems provide job-related info support to users at all levels of a company. Analyze transactional data, generate info needed to manage and control business processes and provide info that leads to better decision-making. Calles (MIS) Management information systems. RFID (radio frequency identification) – Newest development in data acquisition, uses high-frequency radio waves to track physical objects and can track parcels constantly. Knowledge Management Also called expert systems because they stimulate human reasoning by combining a knowledge base and inference rules that determine how the knowledge is applied. Knowledge base consist of large database allowing users to find info by entering keywords or question in normal English phrases. Knowledge management system uses inference rules which are logical rules that identify data patterns and relationships. Do not use strict logical rules but a technique called Fuzzy logic that allow inferences to be drawn from imprecise relationships. Not black and white like binary logic but shades of gray… Results from fuzzy logic search will display in priority order. User Productivity User productivity systems include e-mail, fax, word processing etc. and include Groupware (programs run on a company intranet and enable users to share data, collaborate on projects and work in teams.) Information Systems Integration Most companies require systems that combine TP, Business Support, Knowledge management and user productivity features. 5 What information do users need… Organizational Levels: - Top Managers (develop long-range plans, strategic plans, defining company’s overall mission and goals.) - Middle Managers and knowledge workers (Provide direction, necessary resources and performance feedback to supervisors and team leaders. Focus is shorter time frame and need more detailed info than top managers.) Knowledge workers include professional staff members such as system analysts, programmers, accountants, researchers etc. - Supervisors and Team Leaders (oversee operational employees and carry out day-to-day functions, they coordinate operational tasks and people.) - Operational Employees (include users who rely on TP systems to enter and receive data they need to perform their jobs. SYSTEM DEVELOPMENT TOOLS consist out of: Modeling Prototyping Computer-Aided System Engineering (CASE) Modeling Graphical representation of a concept or process that systems developers can analyze, test and modify. Business model, or Requirements model describes info system must provide. Data model describes data structures and design Object model describes object which combine data and processes Network model describes the design and protocols of telecommunications links Process model describes the logic that programmers use to write code modules Prototyping Test system concepts and provides an opportunity to examine input, output and user interfaces before final decisions are made. Prototype is an early working version of an information system. CASE Uses powerful software, called case tools to help systems analyst develop and maintain IS. Provide overall framework for systems development and support wide variety of design methodologies incl structured analysis and object-oriented analysis. 6 System Development Methods Structured Analysis Object-Oriented Analysis Agile/Adaptive Methods System in terms of data and the processes that act upon that data. Dev is organized into phases with deliverables and milestones to measure progress. SDLC waterfall model (with phases) Data flow diagrams (DFDs) & process descriptions & Business Process modeling Views system in terms of objects that combine data and processes. Objects represent actual people, things, transactions and events. More interactive, use waterfall or model with more iteration Various object-orientated diagrams, actors, methods and messages & Business modeling Intense team-based effort. Dev cycle broken into cycles or iterations that add functionality. Each iteration is designed, built and tested in ongoing process. Spiral model Tools that enhance communications, collaborative software, brainstorming & white boards & Business modeling. Iteration (repetition) possible between 5 phases: 1 Systems Planning (Preliminary Investigation) 2 Systems Analysis (Sys requirement doc) 3 Systems Design (Sys Design Specification) 4 Systems Implementation (Complete Functioning IS) 5 Systems Support and Security (Operational IS) Usually follows series of analysis and design phases similar to the SDLC. Phases tend to be more interactive. Interactive model that can accurately depict real-world business processes. Phases and Tasks (spiral) Planning (Define objectives, constraints and deliverables) Risk Analysis (Identify risks and develop acceptable resolutions) Engineering (Develop prototype that incl all deliverables Education (Perform assessment and testing to develop objectives for next iteration) PRO: Traditional method. Relies on written documentation. Frequent phase iteration can provide flexibility compared to other methods. Wellsuited to project management tools. PRO: Integrates easily with O-O programming languages. Code is modular and reusable reducing cost and development time. Easy to maintain and expand as new objects can be cloned using inherited properties PRO: Flexible and efficient in dealing with change. Stresses team interaction and reflects a set of community-based values. Frequent deliverables constantly validate the project and reduce risk. CON: Changes can be costly. Requirement defined early and can change during development. Users might only be able to describe their needs until they see examples of features and functions. CON: newer so less familiar to Dev team members. Interaction of objects and class can be complex in larger systems. CON: Team members need high level of tech and communication skills. Lack of structure and documentation can introduce risk factors. Overall project might be subject to scope changes as user requirements change. Project Management is process of planning, scheduling, monitoring, controlling and reporting upon the Dev of an IS. 7 STRUCTURED ANALYSIS Based on overall plan similar to a blueprint for constructing a building, called the predictive approach. Technique = process-centered Process model shows data that flows in and out of system processes. Inside each process, input data is transformed by business rules that generate the output. (DFD) Data flow diagram uses various symbols and shapes to represent data flow, processing and storage. In the waterfall model the result of each phase is called a deliverable or end product flowing into next phase. 1 Sys Planning Usually begins with formal request to the IT department, called a system request, describing problems or desired changes in an IS or business process. Purpose of this phase is to perform a preliminary investigation to evaluate an IT-related business opportunity or problem. Key part of preliminary investigation is a feasibility study that reviews anticipated costs and benefits and recommends a course of actions based on operational, technical, economic and time factors. 2 Sys Analysis Purpose is to build a logical model of the new system. Step 1 is requirement modeling where you investigate business processes and document what the new system must do to satisfy users. Perform fact-finding using techniques such as interviews, surveys, doc review, observation and sampling. Results are used to build business models, data and process models, and object models. Deliverable = system requirements document (describes management and user requirements, costs and benefits and outlines alternative Dev strategies. 3 Sys Design Purpose is to create a physical model that will satisfy all documented requirements for the system. Design user interface and identify necessary outputs, inputs and processes. Also design internal and external controls, incl computer-based and manual features guaranteeing reliable, accurate, maintainable and secure sys. Deliverable = system design specification 4 Sys Implementation New sys is constructed. Programs are written, tested and documented and system is installed. Objective = Deliver complete functioning and documented IS. Final Preparation = converting data to new system’s files, training and performing actual transition to new sys. Includes assessment called systems evaluation (determine whether sys operates properly and if costs and benefits are within expectations. 5 Sys Support & Security IT staff maintains, enhances and protects the system. Maintenance changes correct errors and adapt to changes in the environment. Enhancements provide new features and benefits. Objective = maximize ROI Well-designed sys must be secure, reliable, maintainable and scalable. Scalable = design can expand to meet new business requirements and volumes. 8 OBJECT-ORIENTED ANALYSIS Combines data and the processes that act on data into things called objects. (Real-world business processes and operations. And object is a member of a class (collection of similar objects). Objects possess characteristics called properties which is inherited from the class or possesses on it’s own. Instructor and Student fall under person class. Person has property called “address” which is inherited by the instructor and student. Student has property called “major” which is not shared. Built-in processes (methods) can change object’s properties. (an ORDER may have property called “status” that can change. One object can send info to another object using a message (request specific behavior or info from another object). ORDER requests address from CUSTOMER. AGILE METHODS Attempt to develop system incrementally by building series of prototypes and constantly adjusting them to user requirements. Emphasizes continuous feedback and each incremental step is affected by what was learned in prior steps. Iterative DEV boost productivity by using flexible manufacturing system where team-based effort and short-term milestones helped quality up and costs down OTHER DEVELOPMENT METHODS 2 Popular Methodologies: JAD (Joint application development) team-based fact-finding which is only one phase of the Dev process. RAD (Rapid application development) compressed version of entire process. 9 SYSTEM DEV GUIDELINES 5 Basic systems Dev Guidelines Develop a Plan Prepare plan and stick to it, logical sequence Involve Users and carefully listen to them Users must be involved in Dev process, especially when identifying and modeling system requirements Use Project Management Tools and Techniques Keep on track, avoid surprises. Reasonable nr of checkpoints Develop Accurate Cost and Benefit Information Managers need to be informed Remain Flexible Ability to react quickly INFORMATION TECHNOLOGY DEPARTMENT 6 main Functions:  Application Development Provides leadership and overall guidance but systems themselves are developed by teams consisting of users, managers and IT staff members. Popular model is a project-oriented team using RAD or JAD with IT professionals providing overall coordination, guidance and technical support.  Systems Support and Security vital protection and maintenance services for hardware and software, incl enterprise computing systems, networks, TP systems & corporate IT infrastructure. Technical support to other groups in IT department, often includes deployment team (installs and configure workstations)  User Support Provide users with technical info, training and productivity support (help desk or info center)  Database Administration data design, management, security, backup and access.  Network Administration hardware and software maintenance, support and security. Install, configure, manage, monitor and maintain network apps.  Web Support design and construct Web pages, monitor traffic, manage hardware and software and link Webbased apps to company’s info systems, important for companies engaged in e-commerce.  Quality Assurance (QA) reviews and test all apps and system changes to verify specs and software quality standards. 10 SYSTEM ANALYST Investigates, analyzes, designs, develops, installs, evaluates and maintains a company’s IS. Responsibilities = help translate business requirements into IT projects. Help document business profiles, review business processes, select hardware and software packages, design info systems, train users and plan e-commerce Web sites. Plans projects, develops schedules, estimate costs, conducts meetings, delivers presentations and writes memos, reports and documentation. KNOWLEDGE, SKILLS AND EDUCATION Technical Knowledge: State-of-the-art knowledge (internet good resource) learn about technical developments, exchange experiences… attending training courses, on-site and online, Networking with colleagues. Communication Skills: Strong oral and written and ability to interact with people at all levels. Business skills: work closely with managers, supervisors and operational employees, must understand operations and processes. Curious, comfortable with financial tools and able to see the big picture. Critical thinking Skills: include ability to compare, classify, evaluate, recognize patterns, analyze causeand-effect and apply logic. Often use a what-if approach. Education: College degree in IS, computer science or business and some IT experience. Certification: verifies an individual demonstrated a certain level of knowledge and skill on standardized test. 11 GLOSSARY brick-and-mortar Companies conducting business primarily from physical locations business process A specific set of transactions, events, tasks, and results that can be described and documented business process model Graphically displays one or more business processes business process modeling Process used to represent company operations and information needs business profile Company overview; the starting point for the modeling process business support systems Provide job-related information support to users at all levels of a company business-to-business Business sector focused on selling to businesses business-to-consumer Business sector focused on selling to consumers CASE tools Powerful software used to help develop and maintain information systems computer-aided systems engineering Technique that uses CASE tools to help systems analysts develop and maintain information systems data Basic facts that are a system's raw material data model Describes data structures and design deliverable The result of each phase in the waterfall model empowerment Trend to give employees more responsibility and accountability end product Another term for deliverable enterprise applications Company-wide applications enterprise computing Information systems that support company-wide operations and date management requirements expert systems Systems that simulate human reasoning by combining a knowledge base and inference rules extensible markup language Language that allowed company-to-company traffic to migrate to the Internet feasibility study Reviews anticipated costs and benefits and recommends a course of action horizontal system System that can be adapted for use in many different types of companies in-house applications Information systems developed within a company inference rules Logical rules that identify data patterns and relationships knowledge base Large database that allows users to find information by entering keywords in normal English phrases knowledge workers Professional staff members who provide support for the organization's basic functions mission-critical system A system vital to a company's operations modeling Produces a graphical representation of a concept or process Moore's Law Prediction of Gordon Moore that the number of transistors in an integrated circuit would double about every 24 months predictive Approach based on an overall plan process model Describes the logic that programmers use to write code modules product-oriented Companies that manufacture and sell products prototype Early working version of an information system 12 radio frequency identification High-frequency radio waves used to track physical objects requirements model Describes information that a system must provide software Programs that control the hardware and produce the desired information or results software packages Information systems purchased from outside vendors strategic plans Long-range plans that define the company's overall mission and goals structured analysis Traditional method of developing information systems that is still widely used system requirements document Deliverable of systems analysis phase system software Programs that manage system hardware components systems analysis and design Step-by-step process for developing high-quality information systems systems design phase Phase used to create a physical model that will satisfy all documented requirements for the system systems evaluation Assessment to determine whether the system operates properly and if costs and benefits are within expectations systems planning phase Beginning phase starting with a systems request systems request Describes problems or desired changes in an information system or a business process systems support and security Provides vital protection and maintenance services for system hardware and software systems support and security phase Phase during which IT staff maintain, enhance, and protect the system user support Provides users with technical information, training, and productivity support Web support Support function for a company's Internet operations 13 Table of Contents OVERVIEW...................................................................................................................................................14 Strategic planning overview....................................................................................................................14 Business Case..........................................................................................................................................14 Information system projects...................................................................................................................15 Evaluation of systems requests ..................................................................................................................15 Feasibility ....................................................................................................................................................16 Operational feasibility.............................................................................................................................16 Technical feasibility.................................................................................................................................16 Economic feasibility ................................................................................................................................17 Schedule feasibility .................................................................................................................................17 Setting priority ........................................................................................................................................18 Discretionary and nondiscretionary projects..........................................................................................18 Preliminary Investigation overview ........................................................................................................19 Planning Preliminary Investigation – STEPS:.......................................................................................19 Glossary:..................................................................................................................................................22 14 PHASE 2 – BUSINESS JUSTIFICATION OVERVIEW Business case refers to the reasons, justification for a proposal. A strong business case suggests that the company should pursue the alternative, above other options because it would be in the firm’s best interest to do so. Strategic Plan is like a road map for the future. Plan starts with a missions statement which reflects our purpose, vision and values. Strategic planning overview Strategic planning is a dynamic process that identifies specific goals and objectives that support the company’s mission. SWOT analysis: Strengths Weaknesses Opportunities Threats Critical success factors are vital objectives that must be achieved for the company to fulfill its mission. Business Case Should answer following questions:  Why we doing the project  What is the project about  How does this solution address key business issues  Cost and how long  Will productivity loss incur during transition  Return on investment?  Risks of doing and not doing the projects  How to measure success  What alternatives exist? 15 Information system projects Systems request is starting point for most projects – formal way of asking for IT support. Main reasons for Systems Projects:  Improved service  Better performance  Support for new products and services  More info  Stronger controls  Reduced cost Factors affecting system Projects: Internal External  Economy  Governments  Existing systems and data  IT Department  User requests  Top managers  Strategic plan  Technology  Suppliers  Customers  Competitors Evaluation of systems requests Companies use systems review committees or a computer resources committee to evaluate systems projects. Systems request forms are used by some companies to streamline request process and ensures consistency. 16 Feasibility Feasibility tests:  Operational feasibility  Technical feasibility  Economic feasibility  Schedule feasibility Operational feasibility Proposed system will be used effectively after it has been developed. Questions: Does management, users support the project and see the need for change? Will workforce be reduced? Training needed, resources available? Will users be involved in planning right from the start? Will new demands be placed on users, operating changes? Will customers experience adverse effects and for how long? Risk to company’s image or goodwill? Does development schedule conflict with other company priorities? Legal or ethical issues? Technical feasibility Technical resources needed to develop, purchase, install or operate the system. Questions: Does company have necessary hardware, software and network resources, can it be acquired? Needed technical expertise? Does proposed platform have sufficient capacity for future needs, or can it be expanded? Prototype required? Hardware and software environment reliable, will it integrate with other company IS? 17 Economic feasibility Projected benefits of proposed system outweigh the estimated costs TCO (Total cost of ownership), which include ongoing support and maintenance as well as acquisition costs? TCO’s estimated by:  People, IT staff and users  Hardware  Software, including in-house development as well as purchases  Formal and informal training  Licenses and fees  Consulting expenses  Facility costs  Estimated cost of not developing the system or postponing the project. Tangible benefits measured in monetary value… result from decrease in expenses, increase in revenue or both:  New system reducing overtime  Online package tracking system improving service and decreases the need for clerical staff  Sophisticated inventory control system cutting excess invent and eliminates production delays. Intangible benefits Advantages that are difficult to measure in dollars but important:  User-friendly system improving employee job satisfaction  Sales tracking system, better info  New Web site enhancing company’s image. Schedule feasibility Project can be implemented in an acceptable time frame. Interaction between time and costs to be considered.  Can company or IT control factors affection schedule feasibility  Management established firm timetable for project?  Conditions to be satisfied during the development of the system.  Does accelerated schedule pose any risks and are the risks acceptable  Project management techniques available to coordinate and control project  Project manager appointed? 18 Evaluating Feasibility First Step: Identify and weed out system requests that are not feasible. Ongoing task that must be performed throughout systems development process. Setting priority Highest priority goes to projects providing greatest benefit at lowest cost in shortest period of time. But influenced by many factors. Factors affecting priority:  Reducing costs? Where, when, how, how much?  Revenue increase? Where, when, how, how much?  More information, results measurable?  System serve customer better?  Serve organization better?  Implantation in reasonable time period? How long results last?  Necessary resources available? Discretionary and nondiscretionary projects Discretionary = project where management has a choice in implementing them. Nondiscretionary = no choice exists. 19 Preliminary Investigation overview Analyst to conduct study of systems request and recommend specific action. End result of preliminary investigation is a report to management. Planning Preliminary Investigation – STEPS:  STEP 1 Understand problem or opportunity.  STEP 2 Define project scope and constraints  STEP 3 Perform fact-finding - Analyze organizational charts - Conduct interviews - Review documentation - Observe operations - Conduct user survey  STEP 4 Analyze project usability, cost, benefit and schedule data.  STEP 5 Evaluate feasibility - Operational - Technical - Economic - Schedule  STEP 6 Present results and recommendations to management. 20 STEP 1 (Understanding problem): Getting to real cause and not just symptom, popular technique is called fishbone diagram or Ishikawa diagram. Main bone is problem with sub-bones representing possible cause of problem. And then ask questions around these. STEP 2 (Define the project Scope and constraints) Determining project scope means defining the specific boundaries or extent of the project. Projects with a very general (not specific) scope are at risk of expanding gradually without specific authorization, this is called project creep. To avoid this the project scope must be as clearly as possible. Also need to identify constraints (a requirement of condition that system must satisfy or an outcome that the system must achieve – can be hardware, software, time, policy, law or cost.) When examining constraints the following characteristics must be identified:  Present versus Future now or at future time  Internal versus External due to requirement within organization or external force such as government regulation.  Mandatory versus Desirable Absolutely essential or merely desirable? STEP 3 (Fact Finding) Gather data about project usability, costs, benefits and schedules. Involves various techniques.  Analyze organization charts layout of people and position, try and acquire from HR.  Conduct interviews Steps: 1. Determine people to interview 2. Establish objectives 3. Develop interview questions 4. Prepare 5. Conduct interview 6. Document interview 7. Evaluate