ASSIGNMENT CHAPTER 14 from Mr. Tri Djoko Wahjono, Ir, M.Sc

ASSIGNMENT CHAPTER 14

Chapter Review

Discovering Computer (“Living In the Digital World 2011”)

Lecture       :        Mr. Tri Djoko Wahjono, Ir, M.Sc

Student      :        Williem [1701309721]

1. What are the special information requirements of an enterprise-sized corporation?

A large organization, or enterprise, requires special computing solutions because of its size and geographical extent. 

Enterprise computing involves the use of computers in networks, such as LANs and WANs, or a series of interconnected networks to satisfy the information needs of an enterprise. 

Executive management, which includes the highest management positions in a company, needs information to make strategic decisions. 

Middle management, which is responsible for implementing the strategic decisions of executive management, needs information to make tactical decisions. 

Operational management, which supervises the production, clerical, and other non-management employees, needs information to make an operational decision that involves day-to-day activities. 

Non-management employees also need information to perform their jobs and make decisions. Managers use business intelligence (BI), business process management (BPM), and business process automation (BPA) tools to focus on information that is important to the decision-making process.

2. What Information Systems and Software Are Used in the Functional Units of an Enterprise?

An information system is a set of hardware, software, data, people, and procedures that work together to produce information. In an enterprise, the individual functional units have specialized requirements for their information systems. Accounting and financial systems manage transactions and help budget, forecast, and analyze. A human resources information system (HRIS) manages human resources functions. An employee relationship management (ERM) system automates and manages communications between employees and the business. Computer-aided design (CAD) assists engineers in product design, and computer-aided engineering (CAE) tests product designs. Computer-aided manufacturing (CAM) controls production equipment, and computer-integrated manufacturing (CIM) integrates operations in the manufacturing process. Material Requirements Planning (MRP) uses software to help monitor and control processes related to production. A quality control system helps an organization maintain or improve the quality of its products or services and typically includes quality control software. A marketing information system serves as a central repository for marketing tasks. Sales force automation (SFA) software equips salespeople with the electronic tools they need. Distribution systems control inventory, manage and track shipping, and provide information and analysis on warehouse inventory. Customer interaction management (CIM) software manages day-to-day interactions with customers. Web site management programs collect data to help organizations make informed decisions regarding their Web presence. Security software enables the IT department to limit access to sensitive information.

3. What Information Systems Are Used throughout an Enterprise?

Some general purpose information systems, called enterprise-wide systems, are used throughout an enterprise. An office information system (OIS) enables employees to perform tasks using computers and other electronic devices. A transaction processing system (TPS) captures and processes data from day to day business activities. A management information system (MIS) generates accurate, timely, and organized information, so that users can make decisions, solve problems, supervise activities, and track progress. A decision support system (DSS) helps users analyze data and make decisions. An expert system captures and stores the knowledge of human experts and then imitates human reasoning and decision making. Customer relationship management (CRM) systems manage information about customers.  Enterprise resource planning (ERP) provides centralized, integrated software to help manage and coordinate the ongoing activities of an enterprise. A content management system (CMS) is a combination of databases, software, and procedures that organizes and allows access to various forms of documents and files

4. What Are Types of Technologies Used throughout an Enterprise?

Technologies used throughout an enterprise include the following items. A portal is a collection of links, content, and services presented on a Web page and designed to guide users to related to their jobs. A data warehouse is a huge database that stores and manages the data required to analyze historical and current transactions. An enterprise’s communications infrastructure consists of hardware (such as wired and wireless network connections and devices, routers, firewalls, and servers), software (such as e-mail, instant messaging, VoIP, and server management), and procedures for using and managing hardware and software. An extranet allows customers or suppliers to access part of an enterprise’s intranet. Web services allow businesses to create products and B2B interactions over the Internet. Many enterprises employ a service is oriented architecture (SOA) to allow better communications and services between diverse information systems. A document management system (DMS) allows for storage and management of a company’s documents. A workflow application assists in the management and tracking of the activities in a business process from start to finish. A virtual private network (VPN) provides users with a secure connection to a company’s network server.

5. What Are Virtualization, Cloud Computing, and Grid Computing?

• Virtualization is the practice of sharing or pooling computing resources, such as servers and storage devices. Server virtualization provides the capability to divide a physical server logically into many virtual servers; storage virtualization provides the capability to create a single logical storage device from many physical storage devices. 
• Cloud computing is an Internet service that provides computing needs to computer users. Grid computing, which often is used in research environments, combines many servers and /or personal computers on a network to act as one large computer. 
• Cloud and grid computing usually charge a fee based on usage or processing time.

6. What Are the Computer Hardware Needs and Solutions for an Enterprise?

Enterprise hardware allows large organizations to manage and share information and data using devices geared for maximum availability and efficiency. Enterprises use a variety of hardware types to meet their large-scale needs. A RAID (redundant array of independent disks) is a group of integrated disks that duplicates data and information to improve data reliability. Network attached storage (NAS) is a server that provides storage for users and information systems attached to the network. A storage area network (SAN) is a high speed network that provides storage to other servers. An enterprise storage system uses a combination of techniques to consolidate storage so that operations run efficiently. A blade server, sometimes called an ultradense server, packs a complete computer server on a single card, or blade, rather than a system unit. A thin client is a small, terminal-like computer that mostly relies on a server for data storage and processing.

7. What Are High Availability, Scalability, and Interoperability?

• The availability of hardware to users is a measure of how often it is online. A high-availability system continues running and performing at least 99 percent of the time. 
• Scalability is the measure of how well computer hardware, software, or an information system can grow to meet an enterprise’s increasing performance demands. 
• An information system often must share information, or have interoperability, with other information systems within the enterprise.

8. Why Is Computer Backup Important, and How Is It Accomplished?

A backup duplicates a fi le or program to protect an enterprise if the original is lost or damaged. A full, or archival, backup copies all of the programs and files in a computer. A differential backup copies only files that have changed since the last full backup. An incremental backup copies only fi les that have changed since the last full or incremental backup. A selective, or partial, backup allows users to back up specific files. Continuous data protection (CDP), or continuous backup, is a backup plan in which data is backed up whenever a change is made. Backup procedures specify a regular plan

9. What Are the Steps in a Disaster Recovery Plan?

A disaster recovery plan describes the steps a company would take to restore computer operations in the event of a disaster. A disaster recovery plan contains four components. The emergency plan specifies the steps to be taken immediately after a disaster strikes. The backup plan stipulates how a company uses backup fi les and equipment to resume information processing. The recovery plan identifies the actions to be taken to restore full information processing operations. The test plan contains information for simulating disasters and recording an organization’s ability to recover.

ASSINGNMENT CHAPTER 13 from Mr. Tri Djoko Wahjono,Ir, M.Sc

ASSINGNMENT CHAPTER 13

Chapter Review

Discovering Computer (“Living In the Digital World 2011”)

Lecture       :        Mr. Tri Djoko Wahjono,Ir, M.Sc

Student      :        Williem [1701309721]

1. How are machine languages different from assembly languages?

Two types of low-level languages are machine languages and assembly languages. Machine language, known as the first generation of programming languages, is the only language the computer directly recognizes. Machine language instructions use a series of binary digits or a combination of numbers and letters that represents binary digits. The binary digits correspond to the on and off electrical states. As you might imagine, coding in machine language is tedious and time-consuming. With an assembly language, the second generation of programming languages, a programmer writes instructions using symbolic instruction codes. Symbolic instruction codes are meaningful abbreviations. With an assembly language, a programmer writes abbreviations such as A for addition, C for compare, L for load and M for multiply. Assembly languages also use symbolic addresses. A symbolic address is a meaningful name that identifies a storage location. For example, a programmer can use the name RATE to refer to the storage location that contains a pay rate.

2. What is the purpose of procedural programming languages, and what are the features of C and COBOL?

The disadvantages of machine and assembly (low-level) languages led to the development of procedural languages in the late 1950s and 1960s. In a procedural language, the programmer writes instructions that tell the computer what to accomplish and how to do it. With a procedural language, often called a third-generation language (3GL), a programmer uses a series of English-like words to write instructions. For example, ADD stands for addition or PRINT means to print. Many 3GLs also use arithmetic operators such as * for multiplication and 1 for addition. These English-like words and arithmetic symbols simplify the program development process for the programmer. The C programming language, developed in the early 1970s by Dennis Ritchie at Bell Laboratories, originally was designed for writing system software. Today, many programs are written in C (Figure 13-6). This includes operating systems and application software such as word processing and spreadsheet programs. C is a powerful language that requires professional programming skills. Many programmers use C for business and scientific problems. C runs on almost any type of computer with any operating system, but it is used most often with the UNIX and Linux operating systems. COBOL (COmmon Business-Oriented Language) evolved out of a joint effort between the United States government, businesses, and major universities in the early 1960s (Figure 13-7). Naval officer Grace Hopper, a pioneer in computer programming, was a prime developer of COBOL. COBOL is a programming language designed for business applications. Although COBOL programs often are lengthy, their English-like statements make the code easy to read, write, and maintain. COBOL especially is useful for processing transactions, such as payroll and billing, on mainframe computers. COBOL programs also run on other types of computers.

3. What are the characteristics of object-oriented programming languages and program development tools?

Computer programmers use an object-oriented programming (OOP) language or objectoriented program development tool to implement an object-oriented design. Recall from Chapter 12 that an object is an item that can contain both data and the procedures that read or manipulate that data. An object represents a real person, place, event, or transaction. A major benefit of OOP is the ability to reuse and modify existing objects. For example, once a programmer creates an Employee object, it is available for use by any other existing or future program. Thus, programmers repeatedly reuse existing objects. For example, the payroll program and health benefits program both use the Employee object. That is, the payroll program would use it to process employee paychecks and the health benefits program would use it to process health insurance payments. Programs developed using the object-oriented approach have several advantages. The objects can be reused in many systems, are designed for repeated use, and become stable over time. In addition, programmers create applications faster because they design programs using existing objects.

4. What are the uses of other programming languages and other program development tools?

A 4GL ( fourth-generation language) is a nonprocedural language that enables users and programmers to access data in a database. With a nonprocedural language, the programmer writes English-like instructions or interacts with a graphical environment to retrieve data from files or a database. Nonprocedural languages typically are easier to use than procedural languages. Many object-oriented program development tools use 4GLs. One popular 4GL is SQL. As discussed in Chapter 10, SQL is a query language that allows users to manage, update, and retrieve data in a relational DBMS. These powerful languages allow database administrators to define a database and its structure. They also enable users to maintain and access the data in the database.

5. What are web page program development techniques such as HTML and XHTML, XML and WML, scripting languages, DHTML, Ruby on Rails, Web 2.0 Development, and web page authoring software?

HTML (Hypertext Markup Language) is a special formatting language that programmers use to format documents for display on the Web. You view a Web page written with HTML in a Web browser such as Internet Explorer, Safari, Firefox, Opera, or Google Chrome. Similarly, XHTML (extensible HTML) is a markup language that enables Web sites to be displayed more easily on microbrowsers in smart phones and other mobile devices, as well as on desktop and notebook computers. XHTML includes features of HTML and XML. XML (Extensible Markup Language) is an increasingly popular format for sharing data that allows Web developers to create customized tags, as well as use predefined tags, used for developing a single Web site whose content can be formatted to display appropriately on various devices. XML separates the Web page content from its format, allowing the Web browser to display the contents of a Web page in a form appropriate for the display device. For example, a smart phone, a PDA, and a notebook computer all could display the same XML page or use different formats or sections of the XML page. Wireless devices use a subset of XML called WML. WML (wireless markup language) allows Web developers to design pages specifically for microbrowsers. Many smart phones and other mobile devices use WML as their markup language. Programmers write scripts, applets, servlets, or ActiveX controls using a variety of languages. These include some of the languages previously discussed, such as Java, C++, C#, F#, and Visual Basic. Some programmers use scripting languages. A scripting language is an interpreted language that typically is easy to learn and use. Popular scripting languages include JavaScript, Perl, PHP, Rexx, Tcl, and VBScript. Dynamic HTML (DHTML) is a type of HTML that allows Web developers to include more graphical interest and interactivity in a Web page, without the Web page accessing the Web server. That is, the client’s computer automatically updates and changes its own content. These Web pages display much faster than Web pages created with HTML. Ruby on Rails (RoR), also called Rails, is an open source framework that provides technologies for developing object-oriented, database-driven Web sites. Rails uses a free, object-oriented scripting language called Ruby, which is derived from a variety of languages including Ada, LISP, Perl, and Smalltalk. Rails is designed to make Web developers more productive by providing them an easy-to-use environment and eliminating time-consuming steps in the Web development process. Web 2.0 sites often use RSS, previously discussed, and Ajax. Ajax, which stands for Asynchronous JavaScript and XML, is a method of creating interactive Web applications designed to provide immediate response to user requests. Instead of refreshing entire Web pages, Ajax works with the Web browser to update only changes to the Web page. This technique saves time because the Web application does not spend time repeatedly sending unchanged information across the network. Web page authoring software generates HTML and XHTML tags from your Web page design. With Web page authoring software, you can view or modify the HTML or XHTML associated with a Web page. Sometimes, you may add an HTML or XHTML tag that the Web page authoring software does not provide. Learning HTML and XHTML basics will enable you to fine-tune Web page formats created with authoring software.

6. How are popular multimedia authoring programs used?

Multimedia authoring software allows programmers to combine text, graphics, animation, audio, and video in an interactivepresentation. Many programmers use multimedia authoring software for computer based training (CBT) and Web-based training (WBT). Popular Web page authoring programs typically share similar features and are capable of creating similar applications. Popular programs include ToolBook and Director. ToolBook, from SumTotal Systems, has a graphical user interface and uses an object oriented approach, so that programmers can design multimedia applications using basic objects. These objects include buttons, fields, graphics, backgrounds, and pages. Director, from Adobe Systems, is a popular multimedia authoring program with powerful features that allow programmers to create highly interactive multimedia applications.

7. What are the six steps in the program development life cycle?

Program development consists of a series of steps programmers use to build computer programs. As Chapter 12 discussed, the system development life cycle guides information technology (IT) professionals through the development of an information system. Likewise, the program development life cycle (PDLC) guides computer programmers through the development of a program. The program development life cycle consists of six steps :

A. Analyze Requirements

B. Design Solution

C. Validate Design

D. Implement Design

E. Test Solution

F. Document Solution

The steps in the program development life cycle form a loop. Program development is an ongoing process within system development. Each time someone identifies errors in or improvements to a program and requests program modifications, the Analyze Requirements step begins again. When programmers correct errors or add enhancements to an existing program, they are said to be maintaining the program. Program maintenance is an ongoing activity that occurs after a program has been delivered to users, or placed into production.

8. How is structured design different from object oriented design?

In structured design, sometimes called top-down design, the programmer typically begins with a general design and moves toward a more detailed design. This approach breaks down the original set of requirements into smaller, more manageable sections. The first step in top-down design is to identify the major function of a program, sometimes called the main routine or main module. Next, the programmer decomposes (breaks down) the main routine into smaller sections, called subroutines or modules. Then, the programmer analyzes each subroutine to determine if it can be decomposed further. With object-oriented (OO) design, the programmer packages the data and the program (or procedure) into a single unit, an object. When the structure of an object changes, any program that accesses the object automatically accesses the change. The concept of packaging data and procedures into a single object is called encapsulation. That is, an object encapsulates (hides) the details of the object.

9. What are the basic control structures and design tools used in designing solutions to programming problems?

To help document a solution algorithm, programmers use design tools. Two structured design tools are program flowcharts and pseudocode. A design tool for object-oriented design is the UML.

• A program flowchart, or simply flowchart, graphically shows the logic in a solution algorithm. The American National Standards Institute (ANSI) published a set of standards for program flowcharts in the early 1960s. These standards, still used today, specify symbols for various operations in a program’s logic. Programmers connect most symbols on a program flowchart with solid lines. These lines show the direction of the program. Dotted lines on a flowchart connect comment symbols. A comment symbol, also called an annotation symbol, explains or clarifies logic in the solution algorithm.
• Pseudo code uses a condensed form of English to convey program logic. Some programmers prefer to explain the logic of a solution algorithm with words (pseudocode), instead of a graphical flowcharting technique. Pseudo code also uses indentation to identify the control structures. The beginning and ending of the module start at the left margin.

ASSINGNMENT CHAPTER 12 from Mr. Tri Djoko Wahjono

ASSINGNMENT CHAPTER 12

Chapter Review

Discovering Computer (“Living In the Digital World 2011”)

Lecture       :        Mr. Tri Djoko Wahjono, Ir, M.Sc

Student      :        Williem [1701309721]

1.  What Is System Development, and What Are the System Development Phases?

System development is a set of activities used to build an information system. Some system development activities may be performed concurrently. Others are performed sequentially. Depending on the type and complexity of the information system, the length of each activity varies from one system to the next. In some cases, some activities are skipped entirely.

System development activities often are grouped into larger categories called phases. This collection of phases sometimes is called the system development life cycle (SDLC). Many SDLCs contain five phases:

1. Planning

2. Analysis

3. Design

4. Implementation

5. Operation, Support, and Security

Each phase of system development consists of a series of activities, and the phases form a loop. The loop forms when the operation, support, and security phase points to the planning phase. This connection occurs when the information system requires changing. A variety of situations can lead to a change in the information system.

2. What Are Guidelines for System Development?

1. Group activities or tasks into phases: Many SDLCs contain the same phases. Others have more or fewer phases. Regardless, all SDLCs have similar activities. Some SDLCs separate these activities in an additional phase called Construction and Testing. Other differences among SDLCs are the terminology they use, the order of their activities, and the level of detail within each phase.

2. Involve users: Users include anyone for whom the system is being built. Customers, employees, students, data entry clerks, accountants, sales managers, and owners all are examples of users. You, as a user, might interact with an information system at your bank, library, grocery store, fitness center, work, and school. The system development team members must remember they ultimately deliver the system to the user. If the system is to be successful, the user must be included in system development. Users are more apt to accept a new system if they contribute to its design.

3. Define standards: Standards are sets of rules and procedures an organization expects employees to accept and follow. Standards help people working on the same project produce consistent results. For example, one programmer might refer to a product number in a database as a product ID. Others may call it a product identification number, product code, and so on. If standards are defined, then everyone involved uses the same terms, such as product number. Standards often are implemented by using a data dictionary.

3. Why Are Project Management, Feasibility Assessment, Documentation, and Data and Information Gathering Techniques Important?

Project management is the process of planning, scheduling, and then controlling the activities during system development. The goal of project management is to deliver an acceptable system to the user

in an agreed-upon time frame, while maintaining costs. For larger projects, project management activities often are separated between a project manager and a project leader. Some organizations use extreme project management. The project leader identifies the scope of the project, required activities, time estimates, cost estimates, the order of activities, and activities that can take place simultaneously. The project leader records this information in a project plan.

Feasibility is a measure of how suitable the development of a system will be to the organization. A systems analyst typically uses four tests to evaluate feasibility of a project: operational feasibility, which measures how well the proposed system will work; schedule feasibility, which measures whether established project deadlines are reasonable; technical feasibility, which measures whether the organization has or can obtain the hardware, software, and people to deliver and then support the system; and economic feasibility, also called cost/benefit feasibility, which measures whether the lifetime benefits of the proposed system will be greater than its lifetime costs.

Documentation is the collection and summarization of data and information and includes reports, diagrams, programs, or other deliverables. A project notebook contains all documentation for a single project.

 To gather data and information, systems analysts and other IT professionals review documentation, observe, survey, interview, participate in joint-application design ( JAD) sessions, and research.

4. What Activities Are Performed in the Planning Phase?

During the planning phase, four major activities are performed: (1) review and approve the project requests; (2) prioritize the project requests; (3) allocate resources such as money, people, and equipment to approved projects; and (4) form a project development team for each approved project.

The projects that receive the highest priority are those mandated by management or some other governing body. These requests are given immediate attention. The steering committee evaluates the remaining project requests based on their value to the organization. The steering committee approves some projects and rejects others. Of the approved projects, it is likely that only a few will begin system development immediately. Others will have to wait for additional funds or resources to become available.

5.What Is the Purpose of Activities Performed in the Analysis Phase?

(1)   conduct a preliminary investigation

The main purpose of the preliminary investigation, sometimes called the feasibility study, is to determine the exact nature of the problem or improvement and decide whether it is worth pursuing. In this phase, the systems analyst defines the problem or improvement accurately. The actual problem may be different from the one suggested in the project request. The first activity in the preliminary investigation is to interview the user who submitted the project request. Depending on the nature of the request, project team members may interview other users, too. In the case of the school, members of the team might interview the controller for data entry and quality control costs. They also might interview one or two registration clerks, quality control clerks, instructors, and students.

(2)   perform detailed analysis.

Detailed analysis involves three major activities: 

1.  study how the current system works; 
2.  determine the users’ wants, needs, and requirements; 
3.  recommend a solution. 

Detailed analysis sometimes is called logical design because the systems analysts develop the proposed solution without regard to any specific hardware or software. That is, they make no attempt to identify the procedures that should be automated and those that should be manual. During these activities, systems analysts use all of the data and information gathering techniques. They review documentation, observe employees and machines, distribute surveys, interview employees, conduct JAD sessions, and research. An important benefit from these activities is that they build valuable relationships among the systems analysts and users. A major task for the systems analyst is to document these findings in a way that can be understood by everyone.

Both users and IT professionals refer to this documentation.

6.What Are Tools Used in Process Modeling?

Tools that a systems analyst uses for process modeling include entity-relationship diagrams, data flow diagrams, and the project dictionary.

Entity-Relationship Diagrams

 An entity-relationship diagram (ERD) is a tool that graphically shows the connections among entities in a system. An entity is an object in the system that has data. It is important that the systems analyst has an accurate understanding of the system. The systems analyst reviews the ERD with the user. After users approve the ERD, the systems analyst identifies data items associated with an entity.

Data Flow Diagrams

A data flow diagram (DFD) is a tool that graphically shows the flow of data in a system. The key elements of a DFD are the data flows, the processes, the data stores, and the sources.

Project Dictionary

The project dictionary, sometimes called the repository, contains all the documentation and deliverables of a project. The project dictionary helps everyone keep track of the huge amount of details in a system. The dictionary explains every item found on DFDs and ERDs. Each process, data store, data flow, and source on every DFD has an entry in the project dictionary.

7.What Are Tools Used in Object Modeling?

Object modeling, sometimes called object-oriented (OO) analysis and design, combines the data with processes that act on the data into a single unit, called an object. Object modeling can use the same tools as those used in process modeling, but the UML (Unified Modeling Language) has been adopted as a standard notation for object modeling and development. Two common tools in the UML are the use case diagram and the class diagram. A use case diagram graphically shows how actors interact with the information system. An actor is a user or other entity, and the use case is the function that the actor can perform. A class diagram graphically shows classes and one or more lower levels, called subclasses, in a system. Lower levels (subclasses) contain attributes of higher levels (classes) in a concept called inheritance.

8.What Activities Are Performed in the Design Phase?

The design phase consists of two major activities: 

1.  if necessary, acquire hardware and software and 
2.  develop all of the details of the new or modified information system.

 Acquire hardware and software ;when the steering committee approves a solution, the systems analyst begins the activity of obtaining  additional hardware or software or evaluating cloud storage providers that offer the hardware or software to meet the organization’s needs. The activity consists of four major tasks:

1.   identify technical specifications, 
2.  solicit vendor proposals, 
3.  test and evaluate vendor proposals, 
4.   make a decision. 

Detailed design includes developing designs for the databases, inputs, outputs, and programs. During detailed design, many systems analysts use a prototype, which is a working model of the proposed system. Computer-aided software engineering (CASE) products are tools designed to support one or more activities of system development.

9.Why Is Program Development Part of System Development?

During the design phase, an organization can purchase packaged software, which is mass-produced, copyrighted, prewritten software. If suitable packaged software is not available, however, a company may opt for custom software, which is application software developed at the user’s request to match the user’s requirements exactly. Programmers write custom software from the program specification package created during the analysis phase, following an organized set of activities known as the program development life cycle.

10. What Activities Are Performed in the Implementation Phase?

The purpose of the implementation phase is to construct, or build, the new or modified system and then deliver it to the users. System developers perform four major activities in this phase: 

1.  develop programs, 
2. install and test the new system, 
3.  train users
4.  convert to the new system.

The program development life cycle follows these six steps: 

1.  analyze the requirements,  
2. design the solution,  
3. validate the design, 
4.  implement the design,  
5. test the solution, 
6.  document the solution.

Systems analysts and users develop test data so that they can perform various tests. The test data should include both valid (correct) and invalid (incorrect) data. When valid test data is entered, the program should produce the correct results. Invalid test data should generate an error. Tests performed during this step include unit tests, systems tests, integration tests, and acceptance tests.

Users must be trained properly on a system’s functionality. Training involves showing users exactly how they will use the new hardware and software in the system. Some training takes place as one-on-one sessions or classroom style lectures.

The final implementation activity is to change from the old system to the new system. This change can take place using one or more of the following conversion strategies: direct, parallel, phased, or pilot.

11. What Activities Are Performed in the Operations, Support, and Security Phase?

The purpose of the operation, support, and security phase is to provide ongoing assistance for an information system and its users after the system is implemented. The operations, support, and security phase consists of three major activities: 

1.  perform maintenance activities, 
2.  monitor system performance, and 
3. assess system security. 

Organizations today often have a chief security officer (CSO) who is responsible for physical security of an organization’s property and people and also is in charge of securing computing resources. The CSO develops a computer security plan, which summarizes in writing all safeguards that protect the organization’s information assets.

Assignment chapter 11 from Mr. Tri Djoko Wahjono,Ir, M.Sc

ASSINGNMENT CHAPTER 11

Chapter Review

Discovering Computer (“Living In the Digital World 2011”)

Lecture       :         Mr. Tri Djoko Wahjono,Ir, M.Sc

Student       :         Williem [1701309721]

                1.       What are Computer Security Risks, and what are the types of Cybercrime Perpetrators?

Computer security risk is any event or action that could cause a loss of or damage to computer hardware, software, data, information, or processing capability. While some breaches to computer security are accidental, many are intentional. Some intruders do no damage; they merely access data, information, or programs on the computer before logging off. Other intruders indicate some evidence of their presence either by leaving a message or by deliberately altering or damaging data.

Any illegal act involving a computer generally is referred to as a computer crime. The term cybercrime refers to online or Internet-based illegal acts. Perpetrators of cybercrime and other intrusions fall into seven basic categories: hacker, cracker, script kiddies, corporate spy, unethical employee, cyber extortionist, and cyber terrorist.

              2.       What are various Internet and Networking Attacks, and how can Users Safeguard against these attacks?

Various internet and networking attacks are: computer virus, worm, Trojan horse, and rootkit.

A computer virus is a potentially damaging computer program that affects, or infects, a computer negatively by altering the way the computer works without the user’s knowledge or permission. A worm is a program that copies itself repeatedly, for example in memory or on a network, using up resources and possibly shutting down the computer or network. A Trojan horse (named after the Greek myth) is a program that hides within or looks like a legitimate program. A certain condition or action usually triggers the Trojan horse. Unlike a virus or worm, a Trojan horse does not replicate itself to other computers. A rootkit is a program that hides in a computer and allows someone from a remote location to take full control of the computer. Once the rootkit is installed, the rootkit author can execute programs, change settings, monitor activity, and access files on the remote computer.

To take precautions against those malware, do not start a computer with removable media in the drives or ports. Never open an e-mail attachment unless you are expecting the attachment and it is from a trusted source. Disable macros in documents that are not from a trusted source. Install an antivirus program and a personal firewall. Stay informed about any new virus alert or virus hoax. To defend against a botnet, a denial of service attack, improper use of a back door, and spoofing, users can install a firewall, install intrusion detection software, and set up a honeypot.

                3.       What are techniques to prevent Unauthorized Computer Access and Use?

Unauthorized access is the use of a computer or network without permission.

Unauthorized use is the use of a computer or its data for unapproved or illegal activities. Organizations can take measures such as implementing a written acceptable use policy (AUP),

 a firewall, intrusion detection software, an access control, and an audit trail.

Access controls include a user name and password or passphrase, a CAPTCHA, a possessed object, and a biometric device.

Organizations take several measures to help prevent unauthorized access and use. At a mini mum, they should have a written acceptable use policy (AUP) that outlines the computer activities for which the computer and network may and may not be used. An organization’s AUP should specify the acceptable use of computers by employees for personal reasons. Some organizations prohibit such use entirely. Others allow personal use on the employee’s own time such as a lunch hour.

To protect your personal computer from unauthorized intrusions, you should disable file and printer sharing on your Internet connection. Other measures that safeguard against unauthorized access and use include firewalls and intrusion detection software, which were discussed in the previous section, and identifying and authenticating users.

                  4.       What are safeguard against Hardware Theft and Vandalism?

Hardware theft and vandalism are other types of computer security risks. Hardware theft is the act of stealing computer equipment. Hardware vandalism is the act of defacing or destroying computer equipment.

To help reduce the chances of theft, companies and schools use a variety of security measures. Physical access controls, such as locked doors and windows, usually are adequate to protect the equipment. Many businesses, schools, and some homeowners install alarm systems for additional security. School computer labs and other areas with a large number of semi frequent users often attach additional physical security devices such as cables that lock the equipment to a desk, cabinet, or floor. Small locking devices also exist that require a key to access a hard disk or optical disc drive. Some businesses use a real time location system (RTLS) to track and identify the location of high-risk or high-value items.

                 5.       How do software manufacturers protect against software piracy?

To protect themselves from software piracy, software manufacturers issue users license agreements.

A license agreement is the right to use the software. That is, you do not own the software. The license agreement provides specific conditions for use of the software, which a user must accept before using the software. These terms usually are displayed when you install the software. In an attempt to prevent software piracy, Microsoft and other manufacturers have incorporated an activation process into many of their consumer products.

During the product activation, which is conducted either online or by telephone, users provide the software product’s 25-character identification number to receive an installation identification number unique to the computer on which the software is installed. Usually, the software does not function or has limited functionality until you activate it via the Internet or telephone.

                                                                           

                 6.       How does encryption work, and why it is necessary?

Encryption is a process of converting readable data into unreadable characters to prevent unauthorized access. You treat encrypted data just like any other data. That is, you can store it or send it in an e-mail message. In the encryption process, the unencrypted, readable data is called plain text. The encrypted (scrambled) data is called cipher text. An encryption algorithm, or cypher, is a set of steps that can convert readable plain text into unreadable cipher text. Encryption programs typically use more than one encryption algorithm, along with an encryption key. Encryption is used to protect information on the Internet and networks.

                 7.       What types of devices are available to protect computers from system failure?

A system failure is the prolonged malfunction of a computer. System failure also can cause loss of hardware, software, data, or information. A variety of causes can lead to system failure.

A common cause of system failure is an electrical power variation such as noise, an under voltage, or an over voltage.

To protect against electrical power variations, use a surge protector. A surge protector, also called a surge suppressor, uses special electrical components to smooth out minor noise, provide a stable current flow, and keep an over voltage from reaching the computer and other electronic equipment. For additional electrical protection, some users connect an uninterrupted power supply to the computer. An uninterrupted power supply (UPS) is a device that contains surge protection circuits and one or more batteries that can provide power during a temporary or permanent loss of power. A UPS connects between your computer and a power source.

                  8.       What are options for backing up computer resources?

To protect against data loss caused by system failure or hardware/software/information theft, computer users should back up files regularly. A backup is a duplicate of a file, program, or disk that can be used if the original is lost, damaged, or destroyed. Thus, to back up a file means to make a copy of it. In the case of system failure or the discovery of corrupted files, you restore the files by copying the backed up files to their original location on the computer.

You can use just about any media to store backups. Be sure to use high-quality media. A good choice for a home user might be optical discs or external hard disks. Home and business users keep backup copies offsite so that a single disaster, such as a fire, does not destroy both the original and the backup copy of the data. An offsite location can be a safe deposit box at a bank or a briefcase. A growing trend is to use cloud storage as an offsite location. Most backup programs for the home user provide for a full backup and a selective backup. Some users implement a three-generation backup policy to preserve three copies of important files.

            9.       What risks and safeguards are associated with wireless communications?

Although wireless access provides many conveniences to users, it also poses additional security risks. One study showed that about 80 percent of wireless networks have no security protection. Some perpetrators connect to other’s wireless networks to gain free Internet access; others may try to access an organization’s confidential data.

In one technique, called war driving or access point mapping, individuals attempt to detect wireless networks via their notebook computer or mobile device while driving a vehicle through areas they suspect have a wireless network. Some individuals instead use war flying, where they use airplanes instead of vehicles to detect unsecured wireless networks. Once located, some individuals use a GPS device to add the WAP to a war driving access point map on the Internet, making the wireless network vulnerable.

In addition to using firewalls, some safeguards that improve the security of wireless networks include reconfiguring the wireless access point and ensuring equipment uses one or more wireless security standards such as Wi-Fi Protected Access and 802.11i.

•        A wireless access point (WAP) should be configured so that it does not broadcast a network name, known as an SSID (service set identifier). Users should change the default SSID to prevent unauthorized users from accessing their wireless network. The WAP also can be programmed so that only certain devices can access it.

•        Wi-Fi Protected Access (WPA) is a security standard that improves on older security standards by authenticating network users and providing more advanced encryption techniques.

•        An 802.11i network, sometimes called WPA2, the most recent network security standard, conforms to the government’s security standards and uses more sophisticated encryption techniques than WPA.

              10.   How can health-related disorders and injuries due to computer use be prevented?

A repetitive strain injury (RSI) is an injury or disorder of the muscles, nerves, tendons, ligaments, and joints. Computer-related RSIs include tendonitis and carpal tunnel syndrome. For prevented this, OSHA (Occupational Safety and Health Administration) has developed industry-specific and task-specific guidelines designed to prevent workplace injuries with respect to computer usage.

Tendonitis is inflammation of a tendon due to repeated motion or stress on that tendon. Carpal tunnel syndrome (CTS) is inflammation of the nerve that connects the forearm to the palm of the wrist. Repeated or forceful bending of the wrist can cause CTS or tendonitis of the wrist. Symptoms of tendonitis of the wrist include extreme pain that extends from the forearm to the hand, along with tingling in the fingers. Symptoms of CTS include burning pain when the nerve is compressed, along with numbness and tingling in the thumb and first two fingers.  You can take many precautions to prevent these types of injuries. Take frequent breaks during the computer session to exercise your hands and arms. To prevent injury due to typing, place a wrist rest between the keyboard and the edge of your desk. To prevent injury while using a mouse, place the mouse at least six inches from the edge of the desk. In this position, your wrist is flat on the desk. Finally, minimize the number of times you switch between the mouse and the keyboard, and avoid using the heel of your hand as a pivot point while typing or using the mouse.

Another type of health-related condition due to computer usage is computer vision syndrome (CVS). You may have CVS if you have sore, tired, burning, itching, or dry eyes; blurred or double vision; distance blurred vision after prolonged staring at a display device; headache or sore neck; difficulty shifting focus between a display device and documents; difficulty focusing on the screen image; color fringes or after-images when you look away from the display device; and increased sensitivity to light. To ease eyestrain, take these techniques:

•         Every 10 to 15 minutes, take an eye break.

ü  Look into the distance and focus on an object for 20 to 30 seconds.

ü  Roll your eyes in a complete circle.

ü  Close your eyes and rest them for at least one minute.

• •         Blink your eyes every five seconds.
• •         Place your display device about an arm’s length away from your eyes with the top of the screen at eye level or below.
• •         Use large fonts.
• •         If you wear glasses, ask your doctor about computer glasses.
• •         Adjust the lighting.

      11.   What are issues related to information accuracy, intellectual property rights, codes of conduct, and green computing?

•        Computer ethics are the moral guidelines that govern the use of computers and information systems. Seven frequently discussed areas of computer ethics are unauthorized use of computers and networks, software theft (piracy), information accuracy, intellectual property rights, codes of conduct, information privacy, and green computing.

•        Information accuracy today is a concern because many users access information maintained by other people or companies, such as on the Internet. Be aware that the organization providing access to the information may not be the creator of the information. In addition to concerns about the accuracy of computer input, some individuals and organizations raise questions about the ethics of using computers to alter output, primarily graphical output such as a retouched photo. Using graphics equipment and software, users easily can digitize photos and then add, change, or remove images.

•        Intellectual property rights are the rights to which creators are entitled for their work. A copyright gives authors and artists exclusive rights to duplicate, publish, and sell their materials. A copyright protects any tangible form of expression. A common infringement of copyright is piracy. People pirate (illegally copy) software, movies, and music. Many areas are not clear cut with respect to the law, because copyright law gives the public fair use to copyrighted material. The issues surround the phrase, fair use, which allows use for educational and critical purposes.

•        IT code of conduct is a written guideline that helps determine whether a specific computer action is ethical or unethical.

•        Green computing involves reducing the electricity and environmental waste while using a computer. People use, and often waste, resources such as electricity and paper while using a computer.

                     12.   What are issues surrounding information privacy?

•        Information privacy is the right of individuals and companies to deny or restrict the collection and use of information about them. Issues surrounding information privacy include the following. An electronic profile combines data about an individual’s Web use with data from public sources, which then is sold.

•        A cookie is a file that a Web server stores on a computer to collect data about the user. Spyware is a program placed on a computer that secretly collects information about the user. Adware is a program that displays an online advertisement in a banner or pop-up window.

•        Spam is an unsolicited e-mail message or newsgroup posting sent to many recipients or newsgroups at once.

•        Phishing is a scam in which a perpetrator attempts to obtain personal or financial information. The concern about privacy has led to the enactment of many federal and state laws regarding the disclosure of data. As related to the use of computers,

•        Social engineering is defined as gaining unauthorized access or obtaining confidential information by taking advantage of the trusting human nature of some victims and the naivety of others.

•        Employee monitoring uses computers to observe, record, and review an employee’s computer use.

•        Content filtering restricts access to certain materials on the Web.

ASSINGNMENT CHAPTER 10 from Mr. Tri Djoko Wahjono,Ir, M.Sc

ASSINGNMENT CHAPTER 10

Chapter Review Pages 542 – 543

Discovering Computer (“Living In the Digital World 2011”)

Lecture       :         Mr. Tri Djoko Wahjono,Ir, M.Sc

Student      :        Williem [1701309721]

1.      What Is a Database, and How Does a database interact with Data and Information?

A database is a collection of information organized in such a way that a computer program can quickly select desired pieces of data. You can think of a database as an electronic filing system or data base is a collection of data organized in a manner that allows access, retrieval, and use of that data.

To access information from a database, you need a database management system (DBMS). This is a collection of programs that enables you to enter, organize, and select data in a database. Database management system (DBMS) is a software system designed to allow the definition, creation, querying, update, and administration of databases. Database software, often called a database management system (DBMS), allows users to create a computerized database; add, modify, and delete the data; sort and retrieve the data; and create forms and reports from the data. Data is a collection of unprocessed items, which can include text, numbers, images, audio, and video. Computers process data into information. Information is processed data; that is, it is organized, meaningful, and useful. In addition to documents, information can be in the form of audio, images, and video.

2.      What Is Data Integrity, and What Are the Qualities of Valuable Information?

Data integrity refers to maintaining and assuring the accuracy and consistency of data over its entire life-cycle, and is a critical aspect to the design, implementation and usage of any system which stores, processes or retrieves data. Data integrity identifies the quality of data. Data integrity is important because computers and people use information to make decisions and take actions. For a computer to produce correct information, the data that is entered in a database must have integrity.

For information to be valuable, it should be:

·         Accurate information

Accurate information is error free. Inaccurate information can lead to incorrect decisions.

·         Verifiable information

Verifiable information can be proven as correct or incorrect.

·         Timely

                       Timely information has an age suited to its use.

·         Organize

Organized information is arranged to suit the needs and requirements of the decision maker.

·         Accessible

 Accessible information is available when the decision maker needs it.

·         Useful

Useful information has meaning to the person who receives it.

·         Cost-effective

      Cost-effective information should give more value than it costs to produce.

3.       What Is Meant by Character, Field, Record, and File?

·         Character

A bit is the smallest unit of data the computer can process. Eight bits grouped together in a unit comprise a byte. In the ASCII coding scheme, each byte represents a single character, which can be a number (4), letter (R), space, punctuation mark (?), or other symbol (&). The Unicode coding scheme, by contrast, uses one or two bytes to represent a character

·         Field is combination of one or more characters, field is the basic data entry in a record. A field is a combination of one or more related characters or bytes and is the smallest unit of data a user accesses

·         Record is a row of data added to this table. A record is a group of related fields.

·         A data file is a collection of related records stored on a storage medium such as hard disk or optical disc.

4.      What Are File Maintenance Techniques and Validation Techniques?

·         File Maintenance

Refers to the procedures that keep data current. File maintenance procedures include adding records to correct inaccurate data or to update old data with new data, and deleting records when they no longer are needed

·         Validation

Validation is the process of comparing data with a set of rules or values to find out if the data is correct. Many programs perform a validity check that analyzes data, either as you enter it or after you enter it, to help ensure that it is correct. Types of validity checks include an alphabetic check, a numeric check, a range check, a consistency check, a completeness check, and a check digit.

5.      How Is a File Processing Approach Different from the Database Approach?

·         In simple term, a file processing system coordinates only physical access to data. A database organizes and coordinate both physical and logical data access.

·         In file processing data redundancy—same fields stored in multiple file but in Database Approach Reduced data redundancy.

·         In isolated data—data stored in separate files so it is difficult to access but in Database Approach not difficult to access.

·         A database specifically reduces the amount of duplication of data in a system. Additionally, since a database is designed to allow access queries where a file system only allows pre-determined data access, database queries can be far more refined and flexible, as well as granting user access privileges data.

·         Databases, unlike file processing systems, allow multiple protect stored users to access the same data simultaneously. File processing systems are far more restricted on this level.

·         The database's far easier to enforce uniform standards over the data because data can be formatted to fit a particular screen, allowing a single type of data file to be created across the system for example.

·         Database applications are quicker and easier to develop due to standardized components.

·         Due to design, databases are far more flexible as well. They can be adapted far more easily to cope with changing situations than a file processing system.

·         The economy of implementing a database across a huge network is greater than implementing a full file processing system.

·         Databases are essentially easy to install, and are far more user friendly.

·         In a file processing system, each department or area within an organization has its own set of data files. The records in one file may not relate to the records in any other file. Two major weak- nesses of fi le processing systems are redundant data (duplicated data) and isolated data.

·         With a database approach, many programs and users share the data in a database. The database approach reduces data redundancy, improves data integrity, shares data, permits easier access, and reduces development time. A database, however, can be more complex than a file processing system, requiring special training and more computer memory, storage, and processing power than file processing systems.

·         Data in a database also can be more vulnerable than data in file processing systems.

6.      What Functions Are Common to Most Database Management Systems?

a.      The ability to update and retrieve data

This is a fundamental component of a DBMS and essential to database management. Without the ability to view or manipulate data, there would be no point to using a database system.

Updating data in a database includes adding new records, deleting existing records and changing information within a record. The user does not need to be aware of how DBMS structures this data, all the user needs to be aware of is the availability of updating and/or pulling up information, the DBMS handles the processes and the structure of the data on a disk.

b.      Support Concurrent Updates

Concurrent updates occur when multiple users make updates to the database simultaneously. Supporting concurrent updates is also crucial to database management as this component ensures that updates are made correctly and the end result is accurate. Without DBMS intervention, important data could be lost and/or inaccurate data stored.

DBMS uses features to support concurrent updates such as batch processing, locking, two-phase locking, and time stamping to help make certain that updates are done accurately. Again, the user is not aware all this is happening as it is the database management system’s responsibility to make sure all updates are stored properly.

c.       Recovery of Data

In the event a catastrophe occurs, DBMS must provide ways to recover a database so that data is not permanently lost. There are times computers may crash, a fire or other natural disaster may occur, or a user may enter incorrect information invalidating or making records inconsistent.

If the database is destroyed or damaged in any way, the DBMS must be able to recover the correct state of the database, and this process is called Recovery. The easiest way to do this is to make regular backups of information. This can be done at a set structured time so in the event a disaster occurs, the database can be restored to the state that it was last at prior to backup. Backup and recovery is brought to mind whenever there is potential outside threats to a database. For example if there is a power outage, recovery management is how long it takes to recover the database after the outage. Backup management refers to the data safety and integrity; for example backing up all your mp3 files on a disk.

A disadvantage to this is any data or changes entered after the backup would be lost. A way to counteract this is to set the DBMS to provide a feature called Journaling. This involves keeping a log of all updates made to the database, it is maintained in a file separate from the database and can be obtained to re-update the database after it is recovered from the backup.

d.      Security

Security is the prevention of unauthorized users accessing the database. DBMS uses features such as encryption, authentication, authorization and views to provide security to the database. Encryption is when DBMS converts the data in a database to an indecipherable format. No unauthorized person trying to access this information will be able to read it. Authorized users will be able to see it in normal form.

Authentication is a technique in which the database administrator can identify the person accessing the database. Authorized users are given passwords and successful entry of a valid password will allow the user entry into the database, if a password is not successfully entered, the user will be denied access. Authorization is a set of rules that the database administrator (DBA) sets up to specify levels of usage that individuals or groups are allowed to have. Some users may only be allowed viewing options, while others may be allowed to both view/make changes.

In some circumstances, users may only be allowed to access certain pieces of the database, and be denied access to areas that does not relate to their specific needs. In these cases, the DBA will assign workgroups, and these workgroups will be assigned levels of access and permissions. Views are when DBA allows certain users the ability to view the tables or fields that pertain to them, any other view does not exist for them in the database, DBMS does this behind the scenes and to the user it appears that the information they see are the only existing data.

e.       Data Integrity

Data integrity is an important function in database management. This is a set of rules that DBMS provides to see that data integrity is enforced, thus avoiding incorrect or inconsistent data. Types of integrity that DBMS provides are data type, legal values and format. Key integrity also falls into this function of DBMS. This enforces that the primary key of a record remains unique.

7.      What Are Characteristics of Relational, Object-Oriented, and Multidimensional Databases?

A.    Relational Data Base

a.       Stores data in tables that consist of rows and columns

b.      Each row has primary key

c.       Each column has unique name

d.      Stores data relationships

e.       Uses specialized terminology

to a file as a table, a record as a row, and a field as a column. A relationship is a link within the data in a relational database. Structured Query Language (SQL) allows users to manage, update, and retrieve data in a relational database.

B.     An Object-Oriented Database (OODB)

a.       Stores data in objects. An object is an item that contains data, as well as the actions that read or process the data.

b.      Advantages

c.       Can store more types of data

d.      Can access data faster

e.       Often uses object query language (OQL)

f.       Object-oriented databases often use an object query language (OQL) to manipulate and retrieve data.

g.      Applications appropriate for an object-oriented database include a multimedia database, a groupware database, a computer-aided design (CAD) database, a hypertext database, and a hypermedia database.

C.    A Multidimensional Database

a.       Stores data in dimensions.

b.      These multiple dimensions, sometimes known as a hypercube, allow users to access and analyze any view of the database data.

c.       No standard query language exists for multidimensional databases.

d.      One application that uses multidimensional databases is a data warehouse, which is a huge database that stores and manages the data required to analyze historical and current transactions.

e.       A smaller version of a data warehouse is the data mart, which contains a database that helps a specific group or department make decisions.

f.       Multiple dimensions, also called hypercube, allow users to analyze any view of data

g.      Can consolidate data much faster than relational database

8.      How Are Web Databases Accessed?

Database you access through the Web by filling in a form on a Web page usually resides on a database server, a computer that stores and provides access to a database. To access data in a Web database, you fill in a form or enter search text on a Web page, which is the front end to the database. A Web database usually resides on a database server, which is a computer that stores and provides access to a database. One type of program that manages the sending and receiving of data between the front end and the database server is a CGI (Common Gateway Interface) script.

9.      What Are the Responsibilities of Database Analysts and Administrators?

·         A database analyst (DA), or data modeler,

a.       Focuses on the meaning and usage of data.

b.      The DA decides on the placement of fields, defines data relationships, and identifies users’ access privileges.

·          A database administrator (DBA) requires a more technical inside view of the data. In small companies, one person often is both the DA and DBA. In larger companies, the responsibilities of the DA and DBA are split among two or more people.

The DBA is an IT Professional that take care about

A.    Installation

To install a program to the company computer.

B.     Configuration

C.     Upgrade

Checks backup and recovery procedures.

D.    Administration

E.     Monitoring

Monitors database performance

F.      Maintenance

The DBA creates and maintains the data dictionary

G.    Securing

Manages database security