TABLE OF CONTENTS
2. CHAPTER 1: INTRODUCTION TO INFORMATION SYSTEM (IS) ... 3
2.1. Definitions of key terminologies ... 3
2.2. Framework of Information Systems Needed by Managerial End Users ... 5
2.3. Levels of management: ... 5
3. CHAPTER 2: INFORMATION SYSTEMS FOR OPERATIONS, MANAGEMENT AND STRATEGIC ADVANTAGE ... 8
3.1. Importance of Information Systems ... 8
3.2. Disadvantages of MIS ... 9
3.3. Function of MIS ... 9
3.4. MIS Characteristics in General ... 10
4. CHAPTER 3: SYSTEMS APPROACH TO PROBLEM SOLVING AND ITS APPLICATION IN MANAGEMENT ... 10
4.1. What is systems approach? ... 10
4.2. Understanding a Problem or Opportunity ... 11
4.3. Developing a Solution ... 12
4.4. Implementing a Solution ... 13
4.5. Applying the Systems Approach to Information Systems. ... 13
5. CHAPTER 4: INFORMATION SYSTEMS DEVELOPMENT ... 13
5.1. Systems investigations or planning ... 14
5.2. Systems analysis ... 14
5.3. Systems design ... 14
5.4. Systems implementation ... 15
5.5. Post Implementation Review and Support ... 16
6. CHAPTER 5: COMPUTER HARDWARE ... 17
6.1. Definition ... 17
6.2. Input Devices ... 17
6.3. Processor Unit ... 17
6.4. Output devices ... 17
6.5. Storage Devices ... 18
6.6. Networking equipment ... 18
6.7. Types of Computers ... 18
7. CHAPTER 6: COMPUTER SOFTWARE ... 20
7.1. Types of software ... 20
7.2. System Software ... 20
7.3. Firmware ... 20
7.4. Operating systems ... 20
7.5. Utility programs... 21
7.6. Application software ... 21
7.7. Application Packages Used to Support End-User Computing ... 21
8. CHAPTER 7: DATA RESOURCE MANAGEMENT ... 22
8.1. Transaction Processing Systems ... 22
8.2. Transactions Processing Methods ... 22
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8.3. Objectives of Transaction Processing Systems ... 23
13.1. Transaction Processing Activities ... 24
13.2. Transaction Processing Cycle ... 24
13.3. Traditional Transaction Processing Systems ... 26
20. CHAPTER 8: DATABASE MANAGEMENT SYSTEMS ... 26
20.1. Introduction of Database Management Systems... 26
20.2. Types of Databases ... 27
20.3. Flat-file Database Model or Relational Database: ... 28
20.4. Hierarchical Database Model: ... 28
20.5. Network Database Model ... 29
21. CHAPTER 8: TELECOMMUNICATIONS AND NETWORKS ... 30
21.1. Types of networks - according to area coverage... 30
21.2. Local Area Networks (LAN) versus Wide Area Networks (WAN) ... 30
21.3. Types of Network Environment in an Organization ... 31
21.4. Internet ... 31
21.5. Internet Resources (or Services) ... 31
21.6. Internet Protocol (IP) Addressing ... 33
21.7. Data Communication Channels ... 33
21.8. Intranets versus Extranets... 34
21.9. SOCIAL MEDIA IN BUSINESS ... 35
23. CHAPTER 9: E-COMMERCE ... 38
23.1. Understanding E-commerce ... 38
23.2. Types of E-commerce ... 39
23.3. Advantages of E-commerce ... 40
23.4. Disadvantages of E-commerce ... 41
23.5. Benefits of E-commerce ... 43
24. CHAPTER 10: CONTROLLING INFORMATION SYSTEMS ... 44
25.1. Threats to data... 44
25.2. Administrative controls versus system controls ... 44
25.3. Physical versus logical controls ... 45
26.1. Examples of Data Security Controls ... 45
1. CHAPTER 1: INTRODUCTION TO INFORMATION SYSTEM (IS) 1.1. Definitions of key terminologies
System is a collection of related components and has the interaction between them to accomplish a common objective. System will have the following basic interacting components;
System Components/characteristics
1. Purpose / Goal : Mission or objective to accomplish 2. Components : Elements which is known as subsystem 3. Input : Raw materials that enter to the system
4. Output : Results or products/by products of the system
5. Processes : Manipulative functions that convert inputs to outputs
6. Feedback and control: This is an inbuilt mechanism for continuous measurement and review of the status to ensure the system remains on track according to set standards of performance
7. Border / Boundary/Interface : Boundary is the line in between internal and external environment of the system. Interface is the link of interaction between internal and external environment of the system
8. External environment: What is outside the boundary of the system
Virtually all systems are part of a larger system, called a supra-system and likewise, virtually all systems can be decomposed into smaller systems, called subsystems. A system may also be closed or open. A closed system is isolated from its external environment and it neither influences nor is influenced by that external environment; e.g. a vacuum, a controlled experiment, etc. However, business systems are usually open systems. They influence and influenced by their external environments. A system may also be formal or informal. A formal system is official and documented with clear standards and documents such as receipts, order notes, etc. Informal systems on the other hand are not documented they are verbal and include telephone conversations, observations and mental clues. Such information is easily lost unless it is captured in a permanent record. Other systems include deterministic versus probabilistic (stochastic), self organizing (adaptive) versus non adaptive, etc.
Properties of Information and Decision Making Data versus Information
Data: Consists of facts, text, graphics and figure that have not been processed and inadequate for user’s application.
Information: A processed data that is sorted, useful and valuable for particular user
The Characteristics of Valuable Information 1. Accurate
Information must be free from errors.
2. Complete
Information has to contain all the important facts as needed to perform the required processing and what you want to know.
3. Relevant (Communicated to the right user)
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Information must be related to the desired performance or useful to what you’re trying to do.
4. Timely
Information has to be delivered at the right time.
5. Up-to-date or current
Information is useful if it reflects the current state of affairs 6. Cost effective
Cost of producing information in a firm should not exceed the benefit/profit that is obtained from it.
7. Simple or well presented to user (Understandable to user)
Information that has been presented should be easy to understand –format, language, detail level, vocabulary, etc.
8. Security
Only authorized person is allowed to access the information.
9. Confidence of the source e.g. forex mean exchange rates from Central Bank, Billing Rates from previous month data capture logs, etc.
10. Communicated through the right channel
Different users make audience to varied channels e.g. mass media, social media, circulars, mobile SMS alerts, telephone calls, emails, websites, face to face, written print outs, etc.
Information System
Definition: A collection of related components and has the interaction between them to capture data, process it and produce the useful output information to accomplish an objective.
Functions of information system
1. Input : Facts or data from outside the system 2. Processing : Transform the data to information
3. Output : Information that need to be used outside the system 4. Storage : A place to store data for future reference
5. Communication: Transmitting and dissemination of data and information through carrier media
Computer Based Information System (CBIS)
Information system can be categorized into TWO; manual and Computer Based Information System (CBIS). Manual or non-computerized system involves a lot of paper work and user memorization of transactions. Non-computerized is not efficient because it consumes a lot of time to find, process and modify the information. It also involves duplication, more data insecurity and expensive. The CBIS eliminates all these weaknesses.
Roles and function of Computer Based Information System (CBIS)
Same as functions of an information systems, but additional CBIS are adopted for their strategic advantages as covered in the importance of information systems or MIS.
Components of CBIS :
1. Hardware : Hardware can be a single PC, a single main frame or networks of computers. It also includes physical device to control the process of input and output like keyboard, mouse and modem.
2. Software : Application program such as MS Office, Macromedia Dreamweaver and etc.
3. People : Those who are involved with the system or using the system.
4. Data : Consists of facts, text, graphic, figure that can be recorded and that have specific meaning.
5. Procedures : Instructions and rules to design and use information system
1.2. Framework of Information Systems Needed by Managerial End Users
End-users are the various users of Information Systems in the User departments. They can be divided into three managerial end-user levels; operational management (first line managers), tactical management (middle management) and the strategic management (top management).
Each of these managerial end users have differing informational needs dependent on the nature of decisions and the level of planning attended to. A top manager is an upper-level executive who guides and controls the overall activities of the organization. They are responsible for the organization’s planning and developing its mission. They also determine the firm’s strategy and its major policies. They are president, vice president, chief executive officer, and members of the Board. Middle managers develop tactical plans, policies, and they coordinate and supervise the activities of first-line managers. Titles at this level are division manager, department head, plant manager, and operating manager. A first-line manager is a manager who coordinates and supervises the activities of operating employees. They solve day-to-day problems. Common titles for first-line manager include office manager, supervisor, foreman, shift leaders, etc. Operating employees are not managers. They represent the work force of organization.
1.3. Levels of management:
This refers to a pyramid model of the hierarchy of command in an organization. It is a three tier view that conceptualizes management into strategic management, tactical management and operational management.
The middle level management or tactical management comprises of horizontally into areas of management. The most common areas are Administration and Finance, Marketing, Human Resources, Information Technology, Research and Development, etc.
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In view of this organization structure ISs can be categorized according to that management pyramid;
1. Operational Management (First Line Managers) requires Information Systems capable of capturing transactional data from day to day operations. This called a Transaction Processing System (TPS). The system should be capable of processing volume of data captured in organizations transactions such as sales system, inventory system, students’
registration system. The data collected by these systems may be deposited into the organizations Database Management System (DBMS) to be used as raw materials for the Middle Level (tactical managers) Management Information System (MIS). A TPS may be real time or batch based. Real time means data collected is processed immediately for immediate output to aid in a current transaction, e.g. Bank Cashier Terminal Processing System. A batch processing system means data collected is collated together so that it is processed at one go later in the day or another specified time. These systems are easy to automate for they support structured decisions, for example a Bank Cashier Terminal Processing System can be replaced by an ATM. With the power of Internet TPS systems can also be based on Internet infrastructure. An organization can operate a private Internet based TPS where employees can access the organization’s private Internet accessible database to conduct transactions from different branches of the organization such as bank branches network. This called an intranet. These systems can also be extended further to allow customers and suppliers to for example process their orders or track their supplies. Such as a system is called extranet.
Various organizations are also embracing IS systems to provide unique services such as e- commerce, e-ticketing, e-banking, etc.
2. Tactical management: The data collected in the organization DBMS becomes the raw material for producing information for middle level managers. These databases are interrogated by an interface called Management Information System (MIS). Generally speaking an MIS is a system for providing information for managers. It is therefore a general term for an IS. However, specifically MIS refers to an IS for providing information for the middle level of management. It is therefore based on a DBMS that collects data from organization TPS to provide special information depending on the functional management targeted. At this level these MIS may also be called Decision Support Systems (DSS) because the information provided to these tactical managers is meant to aid them in decision making.
A DSS is a system that provides information to aid tactical managers in the decision making roles. The decisions supported are semi-structured. They use partial rules automated in the computer system and partly on the manager’s wisdom and experience. Information used in a DSS is taken from TPS and MIS, in addition to this external information may also be incorporated. With all the information gathered, managers can use models contained within a DSS to look at what might happen if they do certain things. This is a bit like an IF statement that can be changed, scenarios or goal seeking. If a change is made to the figures then the output is increased or decreased.
3. Strategic Management: This is the top most level of management. Their use of information system may not be frequent. However, they need information on exceptional issues of the organization on demand or on the need to know. At some low frequency they may also need regular reports. Such reports are highly summarized and very graphical to allow quick view of the organization at any one point. Executive information systems are used for this purpose. They have very user friendly features such as a dashboard with graphics represent various parameters of interest and allow the CEO to drill down for information and interrogate the report for any finer details they may need. The nature of decisions made by this management is unstructured. They have no clear rules but largely depend on the wisdom and experience of the decision maker. For example a decision on whether to forge a business alliance, how to raise capital, etc. Strategic management may also use Expert Systems to be able to make decisions in areas where they have no adequate expertise. An Expert System is a knowledge-based computer program or artificial intelligence containing expert domain knowledge about objects, events, situations and courses of action, which emulates the process of human experts in the particular domain. In other words, expert system is a computer application that performs a task that would otherwise be performed by a human expert.
Expert systems are extensively used in the medical field. For example, there are expert systems that can diagnose human illness, and MYCIN is one of the popular expert systems in medical field. However, Expert Systems can also be used at other levels of management.
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2. CHAPTER 2: INFORMATION SYSTEMS FOR OPERATIONS, MANAGEMENT AND STRATEGIC ADVANTAGE
2.1. Importance of Information Systems
Information systems in an organization are important to all levels of management to enable managers perform their functions of planning, directing (commanding and leadership), organizing, controlling and coordinating. They are important at operational in execution of specific tasks or transaction/application in the day to day operations of a business, such as accounting, sales, front office automation, etc. However, an organization may identify unique application area that would make the firm stand out among its peers or possibly to offer a service far from ordinary as compared to competitors who are doing business as usual. Such a unique application of IS by a firm is called strategic application.
This is an application that gives the firm an edge above the competitors. It is either using IS to provide a unique service or using IS to provide better services so as to achieve a competitive advantage or edge. For example providing online ticketing, an extranet to allow customers to book a hotel room online, a Just In Time (JIT) system to order a customized luxury car, etc. Ways to gain strategic advantage using IS includes;
1. Cost reduction: A firm can gain profit margin by using IS to reduce number of staff and reduce production time for its products
2. Raise barriers to new entrants: Where an organization provides advanced system more than competitors, new entrants may find it difficult to penetrate, e.g. Safaricom 3G internet while competitors are on GPRS or EDGE technology
3. Establish high switching cost: Where a client has so expensive equipments from the current supplier and the technology cannot migrate to another supplier the customers would remain to avoid migration or switching cost; e.g. switching from one accounting package to another provider may require flesh data entry and expensive data conversion.
4. Creating new products or services: A company can gain strategic positioning by using IS to provide a unique service e.g. Mobile Banking, 24-hour loan processing, etc.
5. Differentiate products or services: An organization may attract customers by convincing them that their product is different from their customers through unique interaction and product features by use of IS.
6. Enhance products or services: Even with current products the company can enhance them such as longer business hours for customers by reducing after office batch processing of daily transactions by use of real time transaction processing system.
7. Establish business alliances: The business can enhance customer experience and product provision by packaging products with other companies, e.g. a holiday package that includes air ticket, hotel, tours and travel, etc by use of IS system inter-linked with other service providers or service advantage smart cards.
8. Locking customers and locking out competitors: Making it impractical for customers or suppliers to deal with competitors for example MPESA agency requirements that your partners do not brand with competitors products
In general, beside these strategic uses of IS, MIS systems are specifically important at various of levels of management to aid in transaction processing and to support management decisions at various levels.
2.2. Advantages and Disadvantages of MIS An MIS provides the following advantages.
1. It Facilitates planning: MIS improves the quality of plants by providing relevant information for sound decision - making. Due to increase in the size and complexity of organizations, managers have lost personal contact with the scene of operations.
2. In Minimizes information overload: MIS change the larger amount of data in to summarized form and there by avoids the confusion which may arise when managers are flooded with detailed facts.
3. MIS Encourages Decentralization: Decentralization of authority is possibly when there is a system for monitoring operations at lower levels. MIS is successfully used for measuring performance and making necessary change in the organizational plans and procedures.
4. It brings Co ordination: MIS facilities integration of specialized activities by keeping each department aware of the problem and requirements of other departments. It connects all decision centres in the organization.
5. It makes control easier: MIS serves as a link between managerial planning and control. It improves the ability of management to evaluate and improve performance. The used computers has increased the data processing and storage capabilities and reduced the cost.
6. MIS assembles, process, stores, Retrieves, evaluates and disseminates the information.
7. Creates strategic advantage for an organization such as cost reduction, product differentiation, etc with end result being higher profitability
The following are some of the disadvantages of MIS:
MIS is highly sensitive: MIS is very helpful in maintaining logging information of an authorized user. This needs to monitor constantly.
Quality of outputs is governed by quality of inputs.
MIS budgeting: There is difficulty in maintaining indirect cost and overheads.
Capturing the actual cost needs to have an accrual system having true costs of outputs which is extremely difficult. It has been difficult to establish definite findings.
MIS is not flexible to update itself for the changes.
The changes in the decision of top level management decrease its effectiveness.
Information accountability is based on the qualitative factors and the factors like morality, confidence or attitude will not have any base.
2.3. Function of MIS
The main functions of MIS are:
Data Processing: Gathering, storage, transmission, processing and getting output of the data. Making the data into information is a major task.
Prediction: Prediction is based on the historical data by applying the prior knowledge methodology by using modern mathematics, statistics or simulation. Prior knowledge varies on the application and with different departments.
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Planning: Planning reports are produced based on the enterprise restriction on the companies and helps in planning each functional department to work reasonably.
Control: MIS helps in monitoring the operations and inspects the plans. It consists of differences between operation and plan with respect to data belonging to different functional department. It controls the timely action of the plans and analyzes the reasons for the differences between the operations and plan. Thereby helps managers to accomplish their decision making task successfully.
Assistance: It stores the related problems and frequently used information to apply them for relative economic benefits. Through this it can derive instant answers of the related problem.
2.4. MIS Characteristics in General
It supports transaction handling and record keeping (Transaction Processing Systems and office automation systems).
It can be integrated with organization wide Database Management System (DBMS) which supports centrally all major functional areas of an organization. This will receive data collected from various operation’s Transaction Processing Systems (TPS)
From the DBMS various managers can interrogate the MIS to obtain information for operational, tactical, and strategic level managers with east access to timely
It supports decision –making function especially acting as a data source for the middle level Decision Support Systems (DSS) for aiding them in their semi-structured decisions.
It is flexible which is needed to adapt to the changing needs of the organization.
It promotes security system by providing only access to authorized users.
MIS not only provides statistical and data analysis but also works on the basis on MBO (management by objectives). MIS is successfully used for measuring performance and making necessary change in the organizational plans and procedures. It helps to build relevant and measurable objectives, monitor results, and send alerts.
3. CHAPTER 3: SYSTEMS APPROACH TO PROBLEM SOLVING AND ITS APPLICATION IN MANAGEMENT
3.1. What is systems approach?
The systems approach is a problem solving technique that stresses a systematic process of problem solving. Problems and opportunities are viewed in a systems context. Studying a problem and formulating a solution becomes an organized system of interrelated activities;
1. Define a problem or opportunity in a systems context.
2. Gather data describing the problem or opportunity 3. Identify alternative solutions.
4. Evaluate each alternative solution.
5. Select the best solution.
6. Implement the selected solution.
7. Evaluate the success of the implemented solution.
These activities and steps of the systems approach can be grouped into a smaller number of stages of problem solving:
a. Understanding a problem or opportunity (steps 1 and 2).
b. Developing a solution (steps 3 through 5).
c. Implementing a solution (steps 6 and 7).
3.2. Understanding a Problem or Opportunity
To solve a problem or pursue an opportunity requires a thorough understanding of the situation at hand. This implies viewing the problem/opportunity in a systematic fashion within a systems context.
1. Defining Problems and Opportunities. Problems and opportunities must be identified when using the systems approach. Symptoms must be separated from problems.
Symptoms are merely signals of underlying problems.
a. A problem is a basic condition that causes undesirable results.
b. An opportunity is a condition that presents the potential for desirable results.
2. Gathering Data and Information. Data and information need to be captured to gain sufficient background into the problem or opportunity situation. In the context of a business systems problem, information gathering may encompass the following:
a. Interviews with employees, customers, and managers.
b. Questionnaires to appropriate end users in the organization.
c. Personal observation or involvement in business operations.
d. Examination of documents, reports, procedures manuals, and other documentation.
e. Inspecting accounting and management reports to collect operating statistics, cost data, and performance results.
f. Development, manipulation, and observation of a model of the business operations or systems affected by the problem or opportunity.
Identifying Current Organizational Systems. In the systems approach, a problem or opportunity must be viewed in a systems context. To understand a problem or opportunity, you must understand both the organizational systems and environmental systems in which a problem or opportunity arises. You must have a systemic view of the situation.
a. A Business as a System. A business faced with a problem or opportunity needs to be viewed as an organizational system operating within a business environment. This concept helps us isolate and better understand how a problem or opportunity may be related to the basic system components of a business.
b. Environmental Systems. A business is a subsystem of society and is surrounded by other systems in the business environment. Proper interrelationships with the economic, political, and social stakeholders within the environment should be maintained. These stakeholders that interact with a business need to be identified, to determine their effect on a problem or solution.
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c. Organizational Subsystems. Typically a business is subdivided into subdivisions that compose the organizational subsystem.
i. These typically represent functional areas such as marketing, manufacturing, and finance, but can also represent geographic areas, product lines, distribution facilities, work groups, etc.
ii. Decomposition is the process of identifying the boundaries of subsystems within a business and determining the relationships between the subsystems. Those subsystems most affected by the problem or opportunity under consideration need to be identified.
d. Relationships Between Systems. A black box approach aids systems professionals in analyzing the relationships and interconnections between subsystems within the firm. In other words, the processing component remains a black box while inputs and outputs of subsystems are studied.
i. Coupling - the process of determining how tight the function of subsystems are connected. e.g., JIT - requires a close association between inventory control and manufacturing.
ii. Decoupling - the process of loosening the connections between systems.
e.g., E-Mail may loosen communications connections within the organization. People can be more efficient by having differing avenues of communication available to them.
e. Evaluating Selected Systems. To understand a problem and solve it, you should try to determine if basic system functions are being properly performed. This should be done within a systems context by looking at inputs, processing, outputs, feedback, and control structures.
f. Determining Objectives, Standards, and Constraints - a systems approach must determine firm objectives, identify standards, and recognize constraints.
3.3. Developing a Solution
Once you understand a problem or opportunity, you can develop an appropriate solution.
3. Designing Alternative Solutions. Jumping immediately from problem definition to a single solution limits your options and robs you of the chance to consider the advantages and disadvantages of several alternatives. Of course, having too many alternatives can obscure the best solution. Alternative solutions may come from past experience, advice of others, simulation of business operations models, and your own intuition and ingenuity. The "doing nothing" option is also a valid alternative.
4. Evaluating Alternative Solutions. To identify the best solution, the proposed alternatives need to be evaluated. The goal of evaluation is to determine how well each alternative solution helps the firm and its selected subsystems meet their objectives.
a. Evaluation criteria - should reflect the firm's objectives and constraints.
b. Cost Benefit Analysis - Every legitimate solution will have some advantages or benefits, and some disadvantages or costs. This process identifies the benefits and costs associated with each alternative solution.
i. Tangible costs - quantified costs such as Hardware, Software and Staff Salaries.
ii. Intangible Costs - difficult to quantify such as Customer goodwill, Employee morale caused by system errors and Installation/conversion problems.
iii. Tangible Benefits - favorable results that the firm has attained such as Decrease in payroll and Decrease in inventory carry.
iv. Intangible Benefits - hard to estimate and include better customer service, and better delivery of customer request(s).
5. Selecting the Best Solution. Once all alternative solutions have been evaluated, they can be compared to each other, and the "best" (most desirable) solution can be selected. Since the solutions are compared based on multiple criteria (some of which may be intangible), this selection is not always a simple process.
3.4. Implementing a Solution
6. Implement the selected solution. Once a solution has been selected, it must be implemented. An implementation plan may have to be developed. A project management effort may be required to supervise the implementation of large projects.
Typically, an implementation plan specifies the activities, resources, and timing needed for proper implementation. This may include:
a. Types and sources of hardware and software.
b. Construction of physical facilities.
c. Hiring and training of personnel.
d. Start-up and operating procedures.
e. Conversion procedures and timetables.
7. Post implementation Review (Evaluate the success of the implemented solution). The focus of the post implementation review is to determine if the implemented solution has indeed helped the firm and selected subsystems meet their system objectives. If not, the systems approach assumes you will cycle back to a previous step and make another attempt to find a workable solution.
3.5. Applying the Systems Approach to Information Systems.
A variety of information systems development methodologies tailor the systems approach to the process of developing information systems solutions to business problems. A firm may experience difficulties in applying the systems process to IS due to: Lack of User Acceptance due to Departmental/unit and/or emotional conflicts, and the Rapidly changing environmental conditions.
4. CHAPTER 4: INFORMATION SYSTEMS DEVELOPMENT
Systems Development Life Cycle (SDLC) or sometimes just Systems Life Cycle (SLC) an Information Systems Development process, used by a systems analyst to develop information systems of high quality that meet or exceeds customer expectations, within time and cost
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estimates, works effectively and efficiently in the current and planned information technology infrastructure, and is cheap to maintain and cost-effective to enhance. SDLC is a systematic approach to problem solving and is composed of several phases, each comprised of multiple steps: systems investigation (systems planning), systems analysis, systems design, systems implementation and post implementation support and maintenance. Due to this sequencing of phases it is also referred to as the waterfall model.
4.1. Systems investigations or planning
Systems investigations or planning are triggered by a user request. It may be initiated by user in the user department or an external environment entity such as government, supplier or customer or a new technology change that demands overhaul of systems, etc. When this occurs a feasibility study should be conducted to determine the extent of the problem – whether the problem really exists, its extent and what happen if the problem is not tackled.
The feasibility study aims to establish whether the problem should actually be solved. One conclusion might be that the problem is too expensive to solve or it is not worthy, or there is no adequate technical capacity to solve it. A decision may be made to buy, lease or outsource or not to buy all together. Areas of feasibility include;
1. Financial feasibility: This aims to establish what are the financial costs for solving the problem and what are the benefits (cost benefit analysis) of solving it.
2. Technical feasibility: Does the necessary technical capacity exist to solve the problem, can it be hired or procured?
3. Operational feasibility: Can the system work in the organization given existing systems?
4. Other feasibility may include social, environmental, political, etc.
4.2. Systems analysis
Systems analysis involves establishing the requirements for solving the problem; such as what technology will be required, what are the financial costs or budget, when to implement or deliver the solution, etc. The completion of this exercise is marked by a SYSTEMS REQUIREMENTS document. This document will act as the invitation for bidders or Request for Quotations (RFQ) to suppliers. The systems analysis may be done by a systems analyst from the IT department or by an external consultant.
4.3. Systems design
Once the suppliers bid for supply of the system detailed in the SYSTEMS REQUIREMENTS in the Invitation to Bid, the suppliers will detail their proposed solutions in line with the systems requirements. This document is called SYSTEMS SPECIFICATIONS. The systems specification document details what systems the supplier proposes to deliver to meet the systems
requirements. The specifications should meet or exceed the systems specifications and should be within the budget of approved by the procurement committee. As an aid to communication the supplier may provide a prototype either a demo version of the system or schematic
drawing of the workings of the system. Once the procurement team is satisfied with the
bidder’s proposal they will draw the purchase order which will act as the contract document for the supplier. It will outline the Terms of Reference for the contractor and will be used to evaluate the final system that will be delivered. The system specifications act as the
BLUEPRINT for the systems design. Further design includes both the logical and the physical design. The logical design is the development of specifications while physical design is the building and testing of the system upon approval by the client.
4.4. Systems implementation
Systems implementation refers to the delivery of the ordered system when the system goes live. This is completed by a project team comprising of members from the contractor and the client department. In order to enhance success and acceptance of the final system, this stage beside the other stages must include representatives for the affected user departments as well as the IT department who will be charged with maintaining the system. For continuity the system could be implemented on phased implementation, pilot change over direct changeover or parallel changeover. Phased implementation may involve piecemeal implementation over a duration of time, pilot change over may involve scaled down number of departments to ensure it works before it is implemented full scale. Direct changeover is when the system is implemented over the entire organization at one go. It is very risky in case the system fails but is quick and cheap. Such changeover should be done during low season of the system usage.
Parallel changeover is when both the old and the new systems are run simultaneously until the team is confident the users have learnt and the system is satisfactory for live running. A team of data conversion may be required to convert data from the old system to the new system. The new system is signed off upon confirmation that it has met the systems requirements and that the contractor has met the specifications. System implementation also involves user training. The system delivered should include systems documentations which become an aid to training and future support. They include systems technical manuals, user manuals and operational/procedure manuals. During this stage if the contractor encounters change in specifications they must apply for change request authorization from the procurement team of the organization.
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4.5. Post Implementation Review and Support Post Implementation Review and Support
after the system has gone live and the contractor has signed off. Whether the contractor is legally bound to continue providing support services after delivery depends on the specifications of the Warranty document and any Service Level Agreements (SLA) established.
For continuity the organization should sign for Scheduled Preventive Maintenance (SPM).
Further to strengthen the internal capacity for support the organization should establish a help desk or an information centre. A help desk is a team of ICT support who have been trained on the new system whereas an information centre is a centre that provides information to a user’s community on frequently asked questions. It may be an office or even a web based FAQ. The supplier may also complement support by online chats, email support and telephone support and to some extent site visits.
Post Implementation Review and Support
Post Implementation Review and Support refers to the services that the users may request after the system has gone live and the contractor has signed off. Whether the contractor is continue providing support services after delivery depends on the specifications of the Warranty document and any Service Level Agreements (SLA) established.
For continuity the organization should sign for Scheduled Preventive Maintenance (SPM).
strengthen the internal capacity for support the organization should establish a help desk or an information centre. A help desk is a team of ICT support who have been trained on the new system whereas an information centre is a centre that provides mation to a user’s community on frequently asked questions. It may be an office or even a web based FAQ. The supplier may also complement support by online chats, email support and telephone support and to some extent site visits.
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refers to the services that the users may request after the system has gone live and the contractor has signed off. Whether the contractor is continue providing support services after delivery depends on the specifications of the Warranty document and any Service Level Agreements (SLA) established.
For continuity the organization should sign for Scheduled Preventive Maintenance (SPM).
strengthen the internal capacity for support the organization should establish a help desk or an information centre. A help desk is a team of ICT support who have been trained on the new system whereas an information centre is a centre that provides mation to a user’s community on frequently asked questions. It may be an office or even a web based FAQ. The supplier may also complement support by online chats, email support
5. CHAPTER 5: COMPUTER HARDWARE 5.1. Definition
Hardware refers to the computer’s physical equipment. They include input devices, the processor, output devices, and storage devices. Hardware can also include data
communication equipment, also called networking equipment.
5.2. Input Devices
Input Devices are used to enter raw data into the system. They include devices for manual human input (keyboard, mouse, trackball, touch screens) and dde - source data automation (interactive touch screens, magnetic card readers, optical recognition, and voice recognition).
Data may be stored for batch processing or processed immediately. Data may be in a form acceptable for another machine or usable by people
5.3. Processor Unit
Processor Unit includes primary storage and the CPU (control unit and arithmetic/logic unit).
The control unit includes instruction registers and control circuits. The control unit (along with the main memory) makes possible the stored program concept of computer operations. The control unit interprets program instructions; control circuits are activated to complete operations and results are stored. The arithmetic/logic unit (ALU) performs all mathematical computations and logical comparisons. Data are transferred as needed from main memory to the arithmetic/logic unit for manipulation and then returned to main memory for additional processing or output.
The CPU physically is a microprocessor that includes the control unit and arithmetic/logic unit mounted on a silicon chip. A multiprocessing operation mode is possible when a computer contains more than one microprocessor.
5.4. Output devices
Output devices produce results of processed data and relay it to the user. The output format can be a hard copy or softcopy. Softcopy output that can be viewed on a monitor or heard over speakers while a hardcopy is a physical or tangible output printed or plotted on paper.
Softcopy output devices include; visual display units and audio output devices. There are several varieties of display units (also called monitors or computer screen). These include CRT monitors and TFT monitors. CRT monitors are huge and bulky. They consume a lot of office space and electricity and the technology has been phased out. TFT monitors are smaller and flat. They consume less office space and are available in different sizes and technologies.
Hardcopy devices include printers and plotters. Plotters produce their output by drawing.
They are mainly used in architectural drawings and with scientific equipments. However, printers have wide application in business for printing out office documents. Printers can be impact or non-impact printers. Impact printers use a hammer mechanism and are therefore noisy but suitable for producing duplicate or multiple documents. Impact printers are represented by dot matrix printers. They are called dot matrix printers because they produce their output in form of matrix of dots by the hammering mechanism and print ribbon. Such
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printers are commonly used by banks and other businesses to produce customer statements and other transaction documents such as deposit or withdrawal slips in a bank (as POS printers, also called E-POS (Electronic Point of Sale) printers). Non-impact printers on the other hand are noiseless and use a variety of technologies to produce their print output. Non- impact printers include inkjet printers, laserjet printers, thermal printers and bubblejet printers. Inkjet printers produce their output by use of liquid ink released in small jets from a cartridge. They are the cheapest options for small offices and home use especially for color printing or multi-functions such as copying, printing and scanning. However, ink cartridges print yield is low - some modifications to use continuous ink supply system (CISS) are available that provide an external ink reservoirs for refilling is available, to create high yield and economical output in a commercial setup. Laserjet printers user laser beams, light sensitive magnetic drum and powdered ink called toner cartridge, with heat roller mechanism to produce glossy and high quality printout. They are expensive but best choice for quality office documents both in monochrome printing and color printing. They may also be available in multi-function including copy, print and scan functions. Thermal printers produce their print by use of heat sensitive paper and thermal transfer unit. They are commonly used as POS (or E-POS) printers in retail outlets, and ETR printers. However, their print copy fades with time as exposed to light. Bubblejet printers on the other hand are supplied in small portable printers for off-the road print out. They produce their copy by use of inkjet bubbles.
Usually the do not need external power for they can be powered by the USB port of the computer or laptop. They are not suitable for commercial application.
5.5. Storage Devices
Storage Devices are divided into primary and secondary storages also called auxiliary storage.
Primary storage includes Read Only Memory (ROM) and Random Access Memory (RAM).
ROM contains the manufacturer’s firm ware but the RAM provides the computer’s working memory. The secondary storage is used for data that are saved for future processing.
Processed data are saved using unique file names to identify the information or program.
Common devices include magnetic disk, optical disc, DVD, USB flash drive, and magnetic tape.
5.6. Networking equipment
Data Communication and Networking equipment: These are devices used for interconnecting of computers and data communication. They include modems, network switches, network cards, routers, bridges, LANs and WANs, Wi-Fi, etc.
5.7. Types of Computers
A computer is a programmable electronic device that receives data to process it using some set of instructions to produce information. There are two basic categories of computers namely, analog and digital computers, but a third category can also be available by combing the two types to create a hybrid computer. Analog computers are computing or tabulating devices that provide continuous measurement of a quantity or physical matter such as an analog clock, analog microwave, analog weigh scale, etc. These equipment have limited application in business and are actually not included in the day to day conversation about computers. The digital computer is represent data and signal in a two state electrical circuit;
OFF or ON which is translated into two digits 0 or 1 which are referred to as Binary Digits (abbreviated as BITS). This is the modern meaning of a computer device.
Therefore, today’s computer systems fall into one of the following categories:
1. Supercomputers 2. Mainframe Computers
3. Minicomputers or Midrange Computers 4. Microcomputers
Supercomputers:
• Most powerful computer made
• Physically they are the largest
• Process huge amounts of data
• Can house thousands of processors
• Relatively rare because of size and cost.
• Used by large corporations, universities and government agencies.
Mainframe Computers
• Used in large organizations like insurance companies, and banks where many people need frequent access to the same data, which is usually organized into one or more databases.
• Airlines, Government Agencies (Federal Aviation Administration and Census Bureau) track information about large populations, individual tax records, payroll, and more.
• Are being used more and more as specialized servers on the World Wide Web, enabling companies to offer secure transactions with customers over the Internet.
• Many enterprises are connecting personal computers and personal computer networks to their mainframe system. This allows access to the mainframe data and services and also enables them to take advantage of local storage and processing, as well as other features of the PC or network.
• Houses an enormous volume of data (literally billions of records)
• Mainframe can occupy entire rooms or even an entire floor of a high-rise building.
Special air conditioning systems are used to keep them cool and on raised floors to accommodate all the wiring needed to connect the system.
Minicomputers
• Abbreviated version of mainframe computers.
• The capabilities are somewhere between mainframes and PC.
• Minicomputers can handle much more input and output than personal computers can.
• Designed for a single user, most are designed to handle multiple terminals.
• Can be used as a server for PC’s Microcomputers
• The microcomputer is “the computer for the masses” and personal computing
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• Microcomputers include the following types: Desktop models, including workstations, notebook computers (laptops), Network Computers (netbooks), Mini laptops and Handheld personal computers, PDAs
6. CHAPTER 6: COMPUTER SOFTWARE 6.1. Types of software
Computer software refers to the set of instructions that are used by the computer for its data processing. Software can be categorized into systems software and application software.
6.2. System Software
System software: refers to a collection of software required by the computer to perform its own internal process. This software includes firmware, operating systems and utility programs.
6.3. Firmware
These are native programs that are loaded to the computer at the point of manufacture and are embedded as a part of the computer basic configuration in Read Only Memory (ROM) chip or its variance equivalent. These programs perform Basic Input Output Systems (BIOS)
functions such as performing Power-On Self Test (POST) or Pre-Operational Self Test when the computer is powered on. In absence of an operating system the firmware will load and await further instructions of the system administrator on the location of the operating system.
They may also include various system drivers and hardware equipment drivers supplied by equipment manufacturer.
6.4. Operating systems
Operating systems: refers to programs that support the basic functions or operations of a computer system. Examples of operating systems include Ms Windows, UNX, Mac Os, Novell Netware, etc. These functions including;
i. Booting a computer (i.e. preparing a computer for use by initializing its hardware and software resources)
ii. Providing user interface: or the human computer interface that enables interaction of a computer user with the computer system e.g. Windows Graphical User Interface (GUI) using Windows Icon Menu and Pointer (WIMP) interactions
iii. Managing memory of the computer: It allocates how the computer memory is utilized during processing
iv. Hardware and software interface: The operating system provides a platform to load hardware drivers and help various hardware added to the computer system to interact with the software
v. System resources management (Interrupt request handling): these include all the resources of the computer apart from the memory management. Each resource in the computer is assigned a unique identity code called IRQ that identifies the priority given to that resource when it calls for attention from the processor
vi. Error handling: during processing the operating system responds to errors that may arise such as output device missing, memory overflow, etc.
vii. Security management: The operating system includes access controls and authentication mechanism to ensure the system maintains its integrity and data reliability and is secure from unauthorized access
6.5. Utility programs
These are programs that expand the capacity of the computer by providing other additional services. They include software developers’ tools such as programming languages – compilers, debuggers, linkers, translators, and assemblers; systems tools and accessories such as antivirus, backup and restore, media players, CD burning software, Adobe Reader, Games, etc.
6.6. Application software
These are user programs that have been developed to deliver a specific functionality for what a user does in his or her day to day operations. This means the application software required by the computer depends on who the user is. Accountants need accounting software, statisticians need statistical packages, school needs a school management system, etc. Further application software is categorized according to nature of its distribution. If the package is available as off-the-shelf then it is referred to as application package, examples include Ms Office packages, QuickBooks, SPSS, etc. If it is tailor-made by in-house development of hired or internal team of software developers it is called be-spoke software. Application packages are cheap for they are mass produced but may not be adequate for unique functionalities of an organization. However, be-spoke software is expensive and many times the developers may choose to package is to sell to other similar organizations.
Depending on the terms of sale, software may also be commercial or open-source.
Commercial software is available for sale and cannot be duplicated or altered without the authority of the owner. Such acts of illegal reproduction are referred to as piracy. However, open-source software is free to use and to modify. However, owners of the software may change for some special rights on services such as installation and support. Over the Internet a number of software can also be downloaded as freeware, shareware, demo versions or commercial software. Freeware are absolutely free to use. Shareware are copyrighted and shared free of charge but a donation may be expected or some limitations may exist if you use it regularly, demo versions are commercial softwares given as trial version to use for a period of time or with limited functionality or with a penalty of carrying developers banner ads.
However, one is expected to purchase the commercial version after working with the demo version.
6.7. Application Packages Used to Support End-User Computing
These refer to a number of application packages used for office automation and by knowledge workers. They can be classified into;
i. Word processors ii. Spreadsheets iii. Databases