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Note for Cyber Security - cs By Abhinay Shrivastav

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Abhinay Shrivastav
Abhinay Shrivastav
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2. 3. 4. 5. Management Information System Workflow System Decision Support System Expert System 1. Transaction Processing System A transaction processing system is an information system for business transactions involving the collection, modification and retrieval of all transaction data. E.g. airline reservation system, electronic transfer of funds, bank account processing. Transaction-Transactions are the basic business operations such as customer orders, purchase orders, receipts, time cards, invoices, and payroll checks in an organization. Types of TPS i. Batch Processing System Batch processing is where the information is collected and stored as a batch but not processed immediately. Batch processing is useful for enterprise that need to process large amounts of data using limited resources. Example: Payment by cheque, Credit card transactions, etc. ii. Online transaction processing(OLTP): OLTP is a system whereby each transaction is processed immediately, without delay of accumulating transactions into batches. The request raised by either customer or any other person are instantly processed by the system. In OLTP, any failure to online systems becomes a costly overhead as all the date requested are retrieved and stored online. E.g. ATM’s, Railway Reservation. 2. Management Information System MIS is used in those organizations where information is required in the form of reports, presentation by management to take decisions. An MIS gathers data from multiple online systems, analyzes the information, and reports data to aid in management decision-making. TPS is only concerned with processing a business transaction. In MIS, the requirement is much higher as different areas like accounts, inventory, sales, purchase, marketing etc. needs to be tightly integrated to provide collective information to management. 3. Workflow Management System

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A workflow management system (WFMS) is a software system for the set-up, performance and monitoring of a defined sequence of tasks, arranged as a workflow. WFMS helps to define, administer and coordinate different business processes. These are used to manage and control the interrelated activities required to perform a business goal. Workflow system operates by performing a set if tasks in a predefined manner. 4. Decision Support Systems A decision support system (DSS) is an information system that supports business or organizational decision-making activities. A DSS analyzes business data and presents it in such a way that the user can make business decisions more easily. Three defining characteristics of DSSs are: 1. An easy-to-use interactive interface 2. models that enable sensitivity analysis, what if analysis, goal seeking, and risk analysis 3. Data from multiple sources - internal and external sources plus data added by the decision maker who may have insights relevant to the decision situation What-if analysis refers to changing assumptions or data in the model to see the impacts of the changes on the outcome. The main difference between management information system and decision support system is that MIS supports structured decision making while the DSS provides support for unstructured or semi-structured decisions. MIS provides such as daily, weekly, and quarterly report of the employee working hours. Whereas DSS supports unstructured and semi-structured decisions such as whether to make-or-buy-or-outsource products, or what new products to develop and introduce into existing markets. Example- If Management needs to decide which product company should be or which discontinued, then DSS is used. MIS provides information to support lower and middle layer managerial decisions or operations. DSS provides information to support specific situations. MIS uses a large volume of data as the input and gives out a summarized report. DSS uses a low volume of data and the output is decision analysis. Expert System Expert system is an information system that emulates the decision-making ability of a human expert. Expert systems are designed to solve complex problems by reasoning through bodies of

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knowledge, represented mainly as if–then rules rather than through conventional procedural code. These systems use Artificial Intelligence to solve the problem that requires human expertise. An Expert system is divided into 2 subsystems:1. The Inference Engine- It applies the rules to the known facts to deduce new facts. 2. The Knowledge Base- Represents Facts and Rules. Eg. If-then ExampleMYCIN is an expert system which provides the expert guidance to individual for medical diagnosis. MYCIN uses artificial intelligence to identify bacteria causing infections, and to recommend antibiotics. Development Cycle of Information System The Systems development life cycle (SDLC) is the traditional systems development method used by most organizations today. The SDLC is a structured framework that consists of sequential processes by which information systems are developed. SDLC include following steps1. System investigation 2. Systems analysis 3. Systems design 4. Development 5. Testing and Integration 6. Implementation 7. Operation and maintenance 1. System Investigation It is the first stage of information system development cycle. The purpose of this phase is to find out the scope of the problem and determine solutions. Resources, time, cost, benefits are considered in this step. The preliminary investigation includes the following tasks: a. List problems, opportunities and directives. b. Negotiate preliminary scope. c. Assess project worth. d. Plan the project. e. Present the project and plan. 1.1 Feasibility study The next task in the systems investigation stage is the feasibility study. The feasibility study determines the probability of success of the proposed systems development project and assesses the project’s technical, economic, and behavioral feasibility. The feasibility study is critically important to the systems development process because, done properly, the study can prevent organizations

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from making costly mistakes (like creating systems that will not work, will not work efficiently, or that people can’t or won’t use). Types of feasibility1. Technical feasibility Technical feasibility determines if the hardware, software, and communications components can be developed and/or acquired to solve the business problem. Technical feasibility also determines if the organization’s existing technology can be used to achieve the project’s performance objectives. 2. Economic feasibility Economic feasibility determines if the project is an acceptable financial risk and if the organization can afford the expense and time needed to complete the project. 3. Behavioral feasibility. Behavioral feasibility addresses the human issues of the project. All systems development projects introduce change into the organization, and people generally fear change. In fact, employees may overtly or covertly resist a new system. The result of Investigation phase is System requirement Specification. A software requirements specification (SRS) is a detailed description of a software system to be developed with its functional and non-functional requirements. Functional Requirement specifies what the system should do. Non functional requirement is a requirement that specifies criteria that can be used to judge the operation of a system, rather than specific behaviors. A system may be required to present the user with a display of the number of records in a database. This is a functional requirement. How up-to-date [update] this number needs to be, is a nonfunctional requirement. If the number needs to be updated in real time, the system architects must ensure that the system is capable of updating the [displayed] record count within an acceptably short interval of the number of records changing. 2. System Analysis It is an in-depth study of end user information needs that produces functional requirements that are used as the basis for the design of a new information system. This stage defines the business problem, identifies its causes, specifies the solution, and identifies the information requirements that the solution must satisfy. The systems analysis stage produces the following information: • Strengths and weaknesses of the existing system • Functions that the new system must have to solve the business problem • User information requirements for the new system The output of system analysis is the set of functional requirements. 3. System Design Systems analysis describes what a system must do to solve the business problem, and systems design describes how the system will accomplish this task. The deliverable of the systems design phase is the technical design that specifies the following:-

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