Office automation refers to the varied computer machinery and software used to digitally create, collect, store, manipulate, and relay office information needed for accomplishing basic tasks and goals. Raw data storage, electronic transfer, and the management of electronic business information comprise the basic activities of an office automation system. In its basic form, information exists as letters, memos, graphs, records, messages, and so on. When that information is electronically transferred, raw data is exchanged between two or more office employees, either at the same or different locations.
The history of modem office automation began with the typewriter and the copy machine, which mechanized previously manual tasks. However, increasingly office automation refers not just to the mechanization of tasks but to the conversion of information to electronic form as well. The advent of the personal computer in the early 1980s revolutionized office automation. Popular operating systems like DOS (Disk Operating System) and user interfaces like Microsoft Corp.'s Windows dominate office computer systems. Today, most offices use at least one commercial computer business application in the course of daily activity. Some large companies like AT&T maintain extensive and complex office automation systems, while smaller companies may employ only a word processor.
In order to process information, office automation systems must allow input of new information and the retrieval of stored information. Input of new information refers to the physical transfer of text, video, graphics, and sound into a computer. Input can be typed into the computer or scanned (digitally reproduced) from another document or source. New advances in input devices frequently allow direct handwritten input or voice dictation. Input of pre-existing information means retrieving the electronic materials from an existing storage area. These storage areas can be finite and local, such as the hard drive on the office PC, or as seemingly infinite and global as the Internet, the worldwide collection of computer networks that is growing every year.
THE BASICS OF OFFICE AUTOMATION
Generally, there are three basic activities of an office automation system: storage of raw data, data exchange, and data management. Within each broad application area, hardware and software combine to fulfill basic functions.
DATA STORAGE AND MANIPULATION
Data storage usually includes office records and other primary office forms and documents. Data applications involve the capture and editing of a file, image, or spreadsheet. Word processing and desktop presentation packages accommodate raw textual and graphical data, while spreadsheet applications enable the easy manipulation and output of numbers. Image applications allow the capture and editing of visual images.
Text-handling software and systems cover the whole field of word processing and desktop publishing. Word processing is the inputting (usually via keyboard) and manipulation of text on a computer. Word processing is frequently the most basic and common office automation activity. Popular commercial word processing applications include Word Perfect (Corel) and Word (Microsoft). Each provides the office user with a sophisticated set of commands to format, edit, and print text documents. One of the most popular features of word processing packages are their preformatted document templates. Templates automatically set up such things as font size, paragraph styles, headers and footers, and page numbers so that the user does not have to reset document characteristics every time they create a new record.
Desktop publishing adds another dimension to text manipulation. By packaging the features of a word processor with advanced page design and layout features, desktop publishing packages easily create documents with text and images, such as newsletters or brochures.
Image-handling software and systems are another facet of office automation. Images, or digital pictures, are representations of visual information. Visual information is an important complement to textual information. Examples of visual information include pictures of documents, photographs, and graphics such as tables and charts. These images are converted into digital files, which cannot be edited the same way that text files can. In a word processor or desktop publishing application, each word or character is treated individually. In an imaging system, the entire picture or document is treated as one whole object. One of the most popular uses of computerized images is in corporate presentations or speeches. Presentation software packages simplify the creation of multimedia presentations that use computer video, images, sound, and text in an integrated information package.
Spreadsheet programs allow the manipulation of numeric data. Early popular spreadsheets like VisiCalc and Lotus 1-2-3 greatly simplified common financial record keeping. Particularly useful among the many spreadsheet options is the ability to use variables in pro forma statements. The pro forma option allows the user to change a variable and have a complex formula automatically recalculated based on the new numbers. Many businesses use spreadsheets for financial management, financial projection, and accounting.
DATA EXCHANGE
The exchange of stored and manipulated information is an equally important component of an office automation system. Electronic transfer is a general application area that highlights the exchange of information between more than one user or participant. Electronic mail, voice mail, and facsimile are examples of electronic transfer applications. Systems that allow instantaneous or "real time" transfer of information (i.e. online conversations via computer or audio exchange with video capture) are considered electronic sharing systems. Electronic sharing software illustrates the collaborative nature of many office automation systems. The distinction between electronic transfer and electronic sharing is subtle but recognizable.
Electronic transfer software and systems allow for electronic, voice, and facsimile transmission of office information. Electronic mail uses computer based storage and a common set of network communication standards to forward electronic messages from one user to another. It is usually possible to relay electronic mail to more than one recipient. Additionally, many electronic mail systems provide security features, automatic messaging, and mail management systems like electronic folders or notebooks. Voice mail offers essentially the same applications, but for telephones rather than computers. Facsimile transmissions are limited to image relay and have suffered in popularity with the increase in the use of the personal computer. One popular alternative, for example, is to send and receive faxes by modem.
Electronic sharing systems offset the limitations of a store-and-forward electronic mail system. Office automation systems that include the ability to electronically share information between more than one user simultaneously are often called groupware. One type of groupware is an electronic meeting system, which allows geographically dispersed participants to exchange information in real time. Participants may be within the same office or building or thousands of miles apart. Long-distance electronic sharing systems usually use a telephone line connection to transfer data, while sharing in a localized area often involves just a local area network of computers (no outside phone line is needed). An interesting byproduct of the electronic sharing functions of an office automation system is telecommuting. A telecommuter works for a business from another location (often home) using a computer and a connection to the office automation system. Telecommuting is an increasingly popular style of work for many office workers and companies.
DATA MANAGEMENT
The last major component of an office automation system offers planning and strategic advantages by simplifying the management of stored information. Task management, tickler systems or reminder systems, and scheduling programs monitor and control various projects and activities within the office. Electronic management systems monitor and control office activities and tasks through timelines, resource equations, and electronic scheduling. As in data exchange, groupware is gaining in popularity for data management. Each member of the work group or larger group may share access to necessary information via the automated office system and groupware.
OFFICE AUTOMATION: PEOPLE, TOOLS,
AND THE WORKPLACE
When considering office automation three main areas need further discussion: people, and how automation affects them; the constantly changing tools used in automation; and the ways in which automation has changed the workplace.
People involved with office automation basically include all users of the automation and all providers of the automation systems and tools. A wide range of people—including software and hardware engineers, management information scientists, and secretaries—use office automation. All are also involved with providing information. This dual role of both provider and user gives rise to two critical issues. First, training of personnel to effectively use an office automation system is essential; the office automation system is only as good as the people who make and use it. Second, overcoming workplace resistance is a must if the full benefits of automation are to be realized. Change is difficult for some workers, yet must occur for a business to remain competitive.
Practical tools for office automation include computer hardware and software currently available in a number of models, applications, and configurations. Two basic microcomputer platforms are DOS (Disk Operating System)-compatible computers and Apple Macintosh systems. Applications such as word processing, database management, and spreadsheets are common and constantly changing. Standards are increasing but still not yet completely integrated into all aspects of office automation. Office automation tools may stand alone (without access to information at other computers) or be networked (with such access). Configuring complex office systems to share information is difficult and involves a considerable staff commitment. Popular local area network software includes Novell NetWare and Lantastic.
Practical workplace issues of office automation often involve the budget and physical considerations involved with creating, exchanging, and managing information. Equipment, rewiring, training, security, and data entry all cost money and require space. Newly recognized medical problems such as repetitive motion syndrome are a significant issue for some people using office automation systems.
Repetitive motion syndrome is a medical disorder associated with lengthy keyboard inputting and seating arrangements. Likewise, environmental safety concerns might also include vision and overall health considerations related to electromagnetic computer emissions.
Telecommuting advances enable an increasing percentage of the workforce to maintain an office at home and, at the same time, provoke considerable debate on the future of the central office. Businesses must comply with software licenses or face lawsuits. Office automation systems can be complex to acquire and costly to administrate for large organizations. The availability of vital office information in such an easily obtained digital format requires considerable thought and preparation for data security.
By integrating raw information with exchange mechanisms and management structuring and guidance, office automation creates advantages as well as disadvantages. Benefits in using electronic management systems include savings in production and service costs as information is quickly routed for optimal office performance.
Office automation can also be cost effective, as powerful microcomputers continue to drop in price. While office automation often mirrors actual paper transaction and activity, an office automation system may also complement the paper system and provide output only available in digital format. Thus, office automation extends the information activities of the office to surpass physical or geographic limitation.
By far the fastest growing segment of the office automation industry is for multifunction peripherals. These machines incorporate a combination of functions into one. The first such machines included a plain paper fax and a color printer in one unit. These products grew quickly to incorporate scanners and related functions. By the late 1990s, these items registered over 100 percent growth rates.
Read more: Office Automation - benefits http://www.referenceforbusiness.com/encyclopedia/Mor-Off/Office-Automation.html#ixzz1PtzqjxL4
Tuesday, June 21, 2011
Monday, June 13, 2011
COMPUTER SECURITY
MODULE ONE
A security system is a set of mechanisms and techniques that protect a computer system, specifically the assets. They are protected against loss or harm including unauthorized access, unauthorized disclosure, and interference of information.
Assets can be categorized into:
Resources – instances of hardware, software, Communication channels, operating environment, documentation and people.
Data – File, databases, messages in transit etc.
A security attack is the act or attempt to exploit vulnerability in a system.
SECURITY GOALS
In order to meet basic business requirements organizations must Endeavor to achieve the following security goals.
Confidentiality – protect information value and preserve the confidentiality of sensitive data. Information should not disclosed without authority.
Integrity – Ensure the accuracy and reliability of the information stored on the computer systems. Information has integrity if it reflects some real world situation.
Availability – Ensure the continued availability of the information system and all its assets to legitimate users at an acceptable level of service or quality of service.
HAZARDS(Exposure) TO INFORMATION SECURITY
An exposure is a form of possible loss or harm. Examples of exposures include:
Unauthorized access resulting in a loss of computing time
Unauthorized disclosure – information revealed without authorization
Destruction especially with respect to hardware and software
Theft
Interference with system operation.
THREATS TO SECURITY
There are three keywords that come up in discussions of computer security issues: Vulnerabilities, threats and countermeasures.
Vulnerability - Is a point where a system is susceptible to attack. A weakness within the system that can potentially lead to loss or harm.
Threat – Is a possible danger to the system. (Could be a person), a thing (faulty piece of equipment), or an event (fire or flood) – Natural disasters
Circumstances that have potential to cause loss or harm / circumstances that have a potential to bring about exposures.
THREATS TO SECURITY
Human error
Disgruntled employees
Greedy employees who sell information for financial gain.
Outsider access – hackers, crackers, criminals, terrorists, consultants, ex-consultants, ex-employees, competitors, government agencies, spies,(industrial, military), disgruntled customers.
Acts of God/natural disasters – earthquakes, floods, hurricanes
Foreign intelligence
Accidents, Fires, Explosion
Equipment failure
Utility outage
Water leaks, toxic spills
Viruses – these are programmed threats
SECURITY CONTROLS
These include:
1.Administrative controls – they include:
Policies – a mechanism for controlling security
Administrative procedures – Ensure that users only do that which they have been authorized to do.
Legal provisions – serve as security controls and discourage some form of physical threats
Ethics
2. Logical security controls – Measures incorporated within the system to provide protection from adversaries who have already gained physical access.
3. Physical controls – Any mechanism that has a physical form e.g. lock ups
4. Environmental controls
PHYSICAL SECURITY
Physical access controls are designed to protect the organization from unauthorized access. They reduce exposure to theft or destruction of data and hardware. These controls should limit access to only those individuals authorized by management. This authorization may be explicit, as in a door lock for which management has authorized you to have a key; or implicit, as in a job description that implies a need to access sensitive reports and documents. Examples of some of the more common access controls are:
Bolting door locks – These locks require the traditional metal key to gain entry. The key should be stamped ‘Do not duplicate’
Combination door locks (cipher locks) – This system uses a numeric keypad or dial to gain entry. The combination should be changed at regular intervals or whenever an employee with access is transferred, fired or subject to disciplinary action. This reduces the risk of the combination being known by unauthorized people.
Electronic door locks – this system uses a magnetic or embedded chip – based plastic card key or token entered into a sensor reader to gain access. A special code internally stored in the card or token is read by the sensor device that then activates the door locking mechanism.
Biometric door locks – An individual’s unique body features, such as voice, retina, fingerprint or signature, activate these locks. This system is used in instances where extremely sensitive facilities must be protected such as in the military.
Manual logging – all visitors a should be required to sign a visitor’s log indicating their name, company represented, reason for visiting and person to see.
Identification badges – (Photo IDs) badges should be worn by all personnel. Visitor badges should be a different color from employee badges for easy identification.
Video cameras – cameras should be located at strategic points and monitored by security guards. Sophisticated cameras can be activated by motion. The video surveillance recording should be retained for possible future playback.
Security guards – guards are very useful if supplemented by video cameras and locked doors. Guards supplied by an external agency should be bonded to protect the organization from loss.
Controlled visitor access – all visitors should be escorted by a responsible employee. Visitors include friends, maintenance personnel, computer vendors, suppliers and external auditors.
Not advertising the location of sensitive data - Facilities such as the computer labs should not be visible or identifiable from the outside that has no windows or directional signs.
Computer terminal locks – these lock devices to the desk, prevent the computer from being turned on, or disengage keyboard recognition, preventing use.
Alarm system – an alarm system should be linked to inactive entry points, motion detectors and the reverse flow of enter or exit only doors. Security personnel should be able to hear the alarm when activated.
LOGICAL SECURITY
Logical Security consists of software safeguards for an organization’s systems, including user identification and password access, authentication, access rights and authority levels.
Logical access controls reduce exposure to unauthorized alteration and manipulation of data and programs. Exposures that exist from accidental or intentional exploitation of logical access control weaknesses include technical exposures and computer crime. Technical exposures:
This is the unauthorized (intentional) implementation or modification of data and software.
Technical exposures
Data diddling – involves changing data before or as it is being entered into a computer.
Trojan horses – involve hiding malicious, fraudulent code in unauthorized computer program. This hidden code will be executed whenever the authorized program is executed. A classic example is the Trojan horse in the payroll – calculating program that shaves a barely noticeable amount off each paycheck and credits it to the perpetrators’ account.
Rounding down – involves drawing off small amounts of money from a computerized transaction or account and routing this amount to a perpetrators’ account.
Salami techniques – involves the slicing of small amounts of money from a computerized transaction and are similar to the rounding down technique. The salami technique truncates the last few digits from the transaction amount so 234.39 become 234.30 or 234.00.
Viruses – are malicious program codes inserted into other executable code that can self replicate and spread from computer to computer, via sharing of removable computer storage devices.
Worms – are destructive programs that may destroy data or utilize tremendous computer and communication resources but do not replicate like viruses. Such programs do not change other programs, but can run independently and travel from machine to a machine across network connections. Worms may also have portions of themselves running on many different machines.
Data leakage – involves siphoning or leaking information out of the computer. This can involve dumping files to paper or can be as simple as stealing computer reports and tapes.
Wire tapping – involve eavesdropping on information being transmitted over telecommunications lines.
VIRUSES
Viruses are a significant and a very real logical access issue. The term virus is a generic term applied to a variety of malicious computer programs. Traditional viruses attach themselves to other executable code, infect the user’s computer, replicate themselves on the user’s hard disk and then damage data, hard disk or files. Viruses usually attack four parts of a computer:
Executable program files
File directory system that tracks the location of all the computer’s files
Boot and system areas that are needed to start the computer
Data files
Control over viruses
Computer viruses are a threat to computers of any type. Their effects can range from the annoying but harmless prank to damaged files and crashed networks. In todays’ environment, networks are the ideal way to propagate viruses through a system. The greatest risk is from electronic mail (email) attachments from friends and and / or anonymous people through the internet. There are two major ways to prevent and detect viruses that infect computers and network systems.
Having sound policies and procedures in place
Technical means, including anti – virus software
POLICIES AND PROCEDURES
Some of the policy and procedure controls that should be in place are:
1. Update virus software scanning definitions frequently
2. Have vendors run demonstrations on their machines, not yours.
3. Enforce a rule of not using shareware without scanning thoroughly for virus
4. Consider encrypting files and then decrypt them before execution
TECHNICAL MEANS
1. Technical methods of preventing viruses can be implemented through hardware and software means. The following are hardware tactics that can reduce the risk of infection:
2. Use boot virus protection(i.e. built-in firmware based virus protection)
3. Use remote booting
4. Use a hardware based password
Software is by far common anti – virus tool. Antivirus software should primarily be used as a preventative control. Unless, updated periodically, anti – virus software will not be an effective tool against viruses.
Examples of anti – virus programs:
• Kerspersky Antivirus
• Norton Antivirus
• Dr.Solomon Tools kit
• Avira
LOGICAL SECURITY FEATURES, TOOLS AND PROCEDURES
1. Logon – IDs and passwords
The logon – ID provides individual’s identification and each user gets a unique logon-ID that can be identified by the system.
Features of passwords
• A password should be easy to remember but difficult for a perpetrator to guess.
• If the wrong password is entered a predefined number of times, typically three, the logon – ID should be automatically and permanently deactivated (or at least a significant period of time)
• Passwords should be changed periodically.
• A password must be unique to an individual
2. Common setup and access rights
Access Rights and Authority Levels are the rights or power granted to users to create, change, delete or view data and files within a system or network. These rights vary from user to user, and can range from anonymous login (Guest) privileges to Superuser (root) privileges. Guest and Superuser accounts are the two extremes, as individual access rights can be denied or granted to each user. Usually, only the system administrator (a.k.a. the Superuser) has the ability to grant or deny these rights.
3. Token devices, one time passwords
A two factor authentication technique such as micro – processor controlled smart cards generates one-time passwords that are good for only one logon session. Users enter this password along with a password they have memorized to gain access to the system. This technique involves something you have (A device subject to theft) and something you know (a personal identification number). Such devices gain their one time password status because of a unique session characteristic (e.g. ID or time) appended to password.
4. Data classification
Computer files, like documents have varying degrees of sensitivity. By assigning classes or levels of sensitivity to computer files, management can establish guidelines for the level of access control that should be assigned. Classifications should be simple, such as high, medium and low. End user managers and the security administrator can use these classifications to assist with determining who should be able to access what.
5. Biometric security control
Biometrics authentication is the measuring of a user’s physiological or behavioral features to attempt to confirm his/her identity. Physiological aspects that are used include fingerprints, eye retinas and irises, voice patterns, facial patterns, and hand measurements. Behavioral aspects that are used include signature recognition, gait recognition, speaker recognition and typing pattern recognition. When a user registers with the system which he/she will attempt to access later, one or more of his/her physiological characteristics are obtained and processed by a numerical algorithm. This number is then entered into a database, and the features of the user attempting to match the stored features must match up to a certain error rate.
A security system is a set of mechanisms and techniques that protect a computer system, specifically the assets. They are protected against loss or harm including unauthorized access, unauthorized disclosure, and interference of information.
Assets can be categorized into:
Resources – instances of hardware, software, Communication channels, operating environment, documentation and people.
Data – File, databases, messages in transit etc.
A security attack is the act or attempt to exploit vulnerability in a system.
SECURITY GOALS
In order to meet basic business requirements organizations must Endeavor to achieve the following security goals.
Confidentiality – protect information value and preserve the confidentiality of sensitive data. Information should not disclosed without authority.
Integrity – Ensure the accuracy and reliability of the information stored on the computer systems. Information has integrity if it reflects some real world situation.
Availability – Ensure the continued availability of the information system and all its assets to legitimate users at an acceptable level of service or quality of service.
HAZARDS(Exposure) TO INFORMATION SECURITY
An exposure is a form of possible loss or harm. Examples of exposures include:
Unauthorized access resulting in a loss of computing time
Unauthorized disclosure – information revealed without authorization
Destruction especially with respect to hardware and software
Theft
Interference with system operation.
THREATS TO SECURITY
There are three keywords that come up in discussions of computer security issues: Vulnerabilities, threats and countermeasures.
Vulnerability - Is a point where a system is susceptible to attack. A weakness within the system that can potentially lead to loss or harm.
Threat – Is a possible danger to the system. (Could be a person), a thing (faulty piece of equipment), or an event (fire or flood) – Natural disasters
Circumstances that have potential to cause loss or harm / circumstances that have a potential to bring about exposures.
THREATS TO SECURITY
Human error
Disgruntled employees
Greedy employees who sell information for financial gain.
Outsider access – hackers, crackers, criminals, terrorists, consultants, ex-consultants, ex-employees, competitors, government agencies, spies,(industrial, military), disgruntled customers.
Acts of God/natural disasters – earthquakes, floods, hurricanes
Foreign intelligence
Accidents, Fires, Explosion
Equipment failure
Utility outage
Water leaks, toxic spills
Viruses – these are programmed threats
SECURITY CONTROLS
These include:
1.Administrative controls – they include:
Policies – a mechanism for controlling security
Administrative procedures – Ensure that users only do that which they have been authorized to do.
Legal provisions – serve as security controls and discourage some form of physical threats
Ethics
2. Logical security controls – Measures incorporated within the system to provide protection from adversaries who have already gained physical access.
3. Physical controls – Any mechanism that has a physical form e.g. lock ups
4. Environmental controls
PHYSICAL SECURITY
Physical access controls are designed to protect the organization from unauthorized access. They reduce exposure to theft or destruction of data and hardware. These controls should limit access to only those individuals authorized by management. This authorization may be explicit, as in a door lock for which management has authorized you to have a key; or implicit, as in a job description that implies a need to access sensitive reports and documents. Examples of some of the more common access controls are:
Bolting door locks – These locks require the traditional metal key to gain entry. The key should be stamped ‘Do not duplicate’
Combination door locks (cipher locks) – This system uses a numeric keypad or dial to gain entry. The combination should be changed at regular intervals or whenever an employee with access is transferred, fired or subject to disciplinary action. This reduces the risk of the combination being known by unauthorized people.
Electronic door locks – this system uses a magnetic or embedded chip – based plastic card key or token entered into a sensor reader to gain access. A special code internally stored in the card or token is read by the sensor device that then activates the door locking mechanism.
Biometric door locks – An individual’s unique body features, such as voice, retina, fingerprint or signature, activate these locks. This system is used in instances where extremely sensitive facilities must be protected such as in the military.
Manual logging – all visitors a should be required to sign a visitor’s log indicating their name, company represented, reason for visiting and person to see.
Identification badges – (Photo IDs) badges should be worn by all personnel. Visitor badges should be a different color from employee badges for easy identification.
Video cameras – cameras should be located at strategic points and monitored by security guards. Sophisticated cameras can be activated by motion. The video surveillance recording should be retained for possible future playback.
Security guards – guards are very useful if supplemented by video cameras and locked doors. Guards supplied by an external agency should be bonded to protect the organization from loss.
Controlled visitor access – all visitors should be escorted by a responsible employee. Visitors include friends, maintenance personnel, computer vendors, suppliers and external auditors.
Not advertising the location of sensitive data - Facilities such as the computer labs should not be visible or identifiable from the outside that has no windows or directional signs.
Computer terminal locks – these lock devices to the desk, prevent the computer from being turned on, or disengage keyboard recognition, preventing use.
Alarm system – an alarm system should be linked to inactive entry points, motion detectors and the reverse flow of enter or exit only doors. Security personnel should be able to hear the alarm when activated.
LOGICAL SECURITY
Logical Security consists of software safeguards for an organization’s systems, including user identification and password access, authentication, access rights and authority levels.
Logical access controls reduce exposure to unauthorized alteration and manipulation of data and programs. Exposures that exist from accidental or intentional exploitation of logical access control weaknesses include technical exposures and computer crime. Technical exposures:
This is the unauthorized (intentional) implementation or modification of data and software.
Technical exposures
Data diddling – involves changing data before or as it is being entered into a computer.
Trojan horses – involve hiding malicious, fraudulent code in unauthorized computer program. This hidden code will be executed whenever the authorized program is executed. A classic example is the Trojan horse in the payroll – calculating program that shaves a barely noticeable amount off each paycheck and credits it to the perpetrators’ account.
Rounding down – involves drawing off small amounts of money from a computerized transaction or account and routing this amount to a perpetrators’ account.
Salami techniques – involves the slicing of small amounts of money from a computerized transaction and are similar to the rounding down technique. The salami technique truncates the last few digits from the transaction amount so 234.39 become 234.30 or 234.00.
Viruses – are malicious program codes inserted into other executable code that can self replicate and spread from computer to computer, via sharing of removable computer storage devices.
Worms – are destructive programs that may destroy data or utilize tremendous computer and communication resources but do not replicate like viruses. Such programs do not change other programs, but can run independently and travel from machine to a machine across network connections. Worms may also have portions of themselves running on many different machines.
Data leakage – involves siphoning or leaking information out of the computer. This can involve dumping files to paper or can be as simple as stealing computer reports and tapes.
Wire tapping – involve eavesdropping on information being transmitted over telecommunications lines.
VIRUSES
Viruses are a significant and a very real logical access issue. The term virus is a generic term applied to a variety of malicious computer programs. Traditional viruses attach themselves to other executable code, infect the user’s computer, replicate themselves on the user’s hard disk and then damage data, hard disk or files. Viruses usually attack four parts of a computer:
Executable program files
File directory system that tracks the location of all the computer’s files
Boot and system areas that are needed to start the computer
Data files
Control over viruses
Computer viruses are a threat to computers of any type. Their effects can range from the annoying but harmless prank to damaged files and crashed networks. In todays’ environment, networks are the ideal way to propagate viruses through a system. The greatest risk is from electronic mail (email) attachments from friends and and / or anonymous people through the internet. There are two major ways to prevent and detect viruses that infect computers and network systems.
Having sound policies and procedures in place
Technical means, including anti – virus software
POLICIES AND PROCEDURES
Some of the policy and procedure controls that should be in place are:
1. Update virus software scanning definitions frequently
2. Have vendors run demonstrations on their machines, not yours.
3. Enforce a rule of not using shareware without scanning thoroughly for virus
4. Consider encrypting files and then decrypt them before execution
TECHNICAL MEANS
1. Technical methods of preventing viruses can be implemented through hardware and software means. The following are hardware tactics that can reduce the risk of infection:
2. Use boot virus protection(i.e. built-in firmware based virus protection)
3. Use remote booting
4. Use a hardware based password
Software is by far common anti – virus tool. Antivirus software should primarily be used as a preventative control. Unless, updated periodically, anti – virus software will not be an effective tool against viruses.
Examples of anti – virus programs:
• Kerspersky Antivirus
• Norton Antivirus
• Dr.Solomon Tools kit
• Avira
LOGICAL SECURITY FEATURES, TOOLS AND PROCEDURES
1. Logon – IDs and passwords
The logon – ID provides individual’s identification and each user gets a unique logon-ID that can be identified by the system.
Features of passwords
• A password should be easy to remember but difficult for a perpetrator to guess.
• If the wrong password is entered a predefined number of times, typically three, the logon – ID should be automatically and permanently deactivated (or at least a significant period of time)
• Passwords should be changed periodically.
• A password must be unique to an individual
2. Common setup and access rights
Access Rights and Authority Levels are the rights or power granted to users to create, change, delete or view data and files within a system or network. These rights vary from user to user, and can range from anonymous login (Guest) privileges to Superuser (root) privileges. Guest and Superuser accounts are the two extremes, as individual access rights can be denied or granted to each user. Usually, only the system administrator (a.k.a. the Superuser) has the ability to grant or deny these rights.
3. Token devices, one time passwords
A two factor authentication technique such as micro – processor controlled smart cards generates one-time passwords that are good for only one logon session. Users enter this password along with a password they have memorized to gain access to the system. This technique involves something you have (A device subject to theft) and something you know (a personal identification number). Such devices gain their one time password status because of a unique session characteristic (e.g. ID or time) appended to password.
4. Data classification
Computer files, like documents have varying degrees of sensitivity. By assigning classes or levels of sensitivity to computer files, management can establish guidelines for the level of access control that should be assigned. Classifications should be simple, such as high, medium and low. End user managers and the security administrator can use these classifications to assist with determining who should be able to access what.
5. Biometric security control
Biometrics authentication is the measuring of a user’s physiological or behavioral features to attempt to confirm his/her identity. Physiological aspects that are used include fingerprints, eye retinas and irises, voice patterns, facial patterns, and hand measurements. Behavioral aspects that are used include signature recognition, gait recognition, speaker recognition and typing pattern recognition. When a user registers with the system which he/she will attempt to access later, one or more of his/her physiological characteristics are obtained and processed by a numerical algorithm. This number is then entered into a database, and the features of the user attempting to match the stored features must match up to a certain error rate.
Thursday, May 26, 2011
DATA COMMUNICATIONS AND COMPUTER NETWORKS
COMPUTER NETWORKING
INTRODUCTION
CHAPTER OVERVIEW
Computer Networks
Types of computer networks
Configurations/topologies
Communication channels
Data Transmission
Wireless networking
Application of computer networks
Emerging issues in Networks
Others
Computer Networks
Is a communications system connecting two or more computers that work to exchange information and share resources (Hardware, software and data). A network may consist microcomputers, or it may integrate microcomputers or other devices with larger computers. Networks may be simple or complex, self-contained or dispersed over a large geographical region.
COMMUNICATION CHANNELS
The transmission media used in communication are called communication channels. Two ways of connecting microcomputers for communication with other equipment is through:-
• Cable
• Air
There five kinds of communication channels used for cable or air connections.
Telephone line (twisted pair) – Made up of copper wires called twisted pair. It is a standard communication channel for both data and voice. (Speed of up to 100 Mbps)
Coaxial cable – A high frequency transmission cable that replaces the multiple wires of telephone lines with a single solid copper core. It has over 80 times the transmission capacity of twisted pair. It is often used to link parts of a computer system in one building (Speed of up to 600 Mbps)
Fibre-optic cable – Transmits data as pulses of light through tubes of glass. It has over 26,000 times the transmission capacity of twisted pair. A fibre-optic tube can be half the diameter of human hair. Fibre-optic cables are immune to electronic interference and more secure and reliable. Fibre optic cable is rapidly replacing twisted pair (telephone).
Microwave – Transmit data as high-frequency transmission radio waves that travel in straight lines through air.
Satellite – Used to amplify and relay microwave signals from one transmitter on the ground to another. They orbit about 22,000 miles above the earth. They rotate at a precise point and speed and can be used to send large volumes of data. Bad weather can sometimes interrupt the flow of data from a satellite transmission.
TYPES OF COMPUTER NETWORKS
Terms used to describe computer networks:
Node – any device connected to a network such as a computer, printer or data storage device.
Client – a node that requests and uses resources available from other nodes. Typically a micro-computer.
Server – a node that shares resources with other nodes. May be called a file server, printer server, communication server, web server or a database server.
Network Operating System (NOS) - The operating system of the network that controls and coordinates the activities between computers on a network, such as electronic communication and sharing of information and resources.
Distributed processing – Computing power is located and shared at different locations. Common in decentralized organizations (each office has its own computer system but is networked to the main computer)
Host computer – a large centralized computer, usually a minicomputer or mainframe.
Data transmission: Analog versus digital
Information is available in analogue or in digital form. Computer-generated data can easily be stored in a digital format, but analog signals, such as speech and video must first be sampled at regular intervals and then into a digital form. This process is known as digitization and has the following advantages:
• Digital data is less affected by noise
• Extra information can be added to digital signals so that errors can either be detected or corrected.
• Digital data tends to be not to degrade over time
• Processing digital data is relatively easy.
Direction of data transmission
There are three directions or modes of data flow in a data communication system.
1. SIMPLEX COMMUNICATION – Data travels in one-direction only e.g. Point-of-sale terminals
2. HALF-DUPLEX COMMUNICATION – Data flows in both directions, but not simultaneously. E.g. Electronic bulletin board
3. FULL DUPLEX COMMUNICATION – Data is transmitted back and fourth at the same time e.g. mainframe communications
Modes of data transmission
Data may be sent over communication channels in either asynchronous or synchronous mode.
Asynchronous transmission – data is sent and received one byte at a time. Used with microcomputers and terminals with slow speeds.
Synchronous transmission – data is sent and received several bytes (blocks) at a time. It requires a synchronized clock to enable transmission at timed intervals.
TYPES OF COMPUTER NETWORKS
Different communication channels allow different types of networks to be formed. Telephone lines may connect communications equipment within the same building. Coaxial cable or fibre-optic cable can be installed on building walls to form communication networks. Communication networks also differ in geographical size. Three important networks according to geographical size are:
1. LANs
2. MANs
3. WANs
LOCAL AREA NETWORK (LAN)
A LAN is a computer network in which computers and peripheral devices are in close proximity. It is a collection of computer within a single office or building that connects to a common electronic connection – commonly known as a network backbone. This type of network typically uses micro-computers in a bus organization linked with telephone, coaxial, or fibre-optic cable. A LAN allows all users to share hardware, software and data on the network. Minicomputers, mainframes or optical disk storage can be added to the network. A network bridge device may be used to link a LAN to other networks with the same configuration. A network gateway may be used to link a LAN to other networks, even if their configurations are different.
METROPOLITAN AREA NETWORK (MAN)
A MAN is a computer network that may be citywide. This type of network may be used as a link between office buildings in a city. The use of cellular phone system expands the flexibility of a MAN network by linking car phones and portable phones to the network.
WIDE AREA NETWORK (WAN)
A WAN is a computer network that may be countrywide or worldwide. It normally connect networks over a large physical area, such as in different buildings, towns or even countries. A modem connects a LAN to a WAN when the WAN connection is an analogue line. For digital connection a gateway connects one type of LAN to another LAN, or WANS, and a bridge connects a LAN to similar types of LAN. This type of network typically uses microwave relays and satellites to reach users over long distances. The widest of all WANs is the internet, which spans the entire globe.
CONFIGURATIONS/TOPOLOGIES
A computer network configuration is also called network topology. The topology is the method of arranging and connecting the nodes of a network. There are four principal network topologies:
1. Star network
2. Bus network
3. Ring network
4. Hierarchical (hybrid) network
STAR NETWORK
In a star network there are a number of small computers or peripheral devices linked to a central unit called hub. The central unit may be a host computer or a file server. All communications pass through the central unit and control is maintained by polling. This type of network can be used to provide a time- sharing system and is common for linking micro-computers to a mainframe.
Star network
Advantages of star network
It is easy to add new and remove nodes
A node failure does not bring down the entire network
It is easier to diagnose network failures through a central hub
Disadvantages of star network
If the central hub fails the whole network ceases to function
It costs more to cable a star configuration than other topologies
BUS NETWORK
In a bus network each device handles its communication control. There is no host computer, however there may be a file server. All communications travel along a common connecting cable called a bus. It is a common arrangement for sharing data stores on different microcomputers. It is not as efficient as star network for sharing common resources, but is less expensive. The distinguishing feature is that all devices (nodes) are linked along one communication line – with endpoints – called the bus or backbone.
Advantages of bus network
• Reliable in very small networks as well as easy to use and understand.
• Requires the least amount of cable to connect the computers together and therefore is less expensive than other cabling arrangements.
• Is easy to extend. Two cables can be easily joined with a connector, making a longer cable for more computers to join the network. A repeater can also be used to extend a bus configuration.
Disadvantages of bus network
• Heavy network traffic can slow a bus considerably. Because any computer can transmit at any time, bus networks do not coordinate when information is sent. Computers interrupting each other can use a lot of bandwidth.
• Each connection between two cables weaken the electrical signals.
• The bus configuration can be difficult to troubleshoot. A cable break or malfunctioning computer can be difficult to find and can cause the whole network to stop functioning.
RING NETWORK
In ring network each device is connected to two other devices, forming a ring. There is no central file server or computer. Messages are passed around the ring until they reach their destination. Often used to link mainframe, especially over wide geographical areas. It is used in decentralized organization called a distributed data processing.
Advantages of Ring network
• Offer high performance for a small number of workstations or for larger networks where each station has a similar work load.
• Can span longer distances than other types of networks.
• Ring networks are easily extendable.
Disadvantages of Ring network
• Relatively expensive and difficult to install
• Failure of one component of the network can lead to failure of the entire network
• It is difficult to troubleshoot the entire network.
• Adding or removing computers can disrupt the network.
HIERARCHICAL (HYBRID) NETWORK
A hierarchical network consists of several computers linked to a central host computer. It is similar to a star network. Other computers are also hosts to other, smaller computers or to peripheral devices in this type of network. It allows various computers to share databases, processing power, and different output devices. It is useful in centralized organizations.
Advantages of Hybrid Network
• Improves sharing of data and programs across the network
• Offers reliable communication between nodes
Disadvantages of Hybrid Network
• Difficult and costly to install and maintain
• Difficult to troubleshoot network problems
COMPONENTS AND DEVICES OF A NETWORK
All types of computer networks whether wireless or wired requires hardware and software components when it is established. There are many types of hardware devices which are either installed or connected to the computer terminals in order to construct a network.
1. BRIDGE – Links two networks of the same type.
2. GATEWAY – Connects two networks of the dissimilar type.
3. ROUTER – A router is required to connect multiple networks, like your LAN to the Internet. Routers work by storing large tables of networks and addresses, then using algorithms to determine the shortest routes to individual addresses within those networks. In this way efficient routers not only facilitate intra-network communications, but also play a role in overall network performance. delivering the information faster.
4. SWITCH - A network switch is a small hardware device that joins multiple computers together within one local area network (LAN). Technically, network switches operate at layer two (Data Link Layer) of the OSI model.
Client/Server environment
A client/Server network environment is one in which one computer acts as a server and provides data distribution and security functions to other computers that are independently running various applications. An example of the simplest client/server model is a LAN whereby a set of computers is linked to allow individuals to share data.
NETWORK PROTOCOLS
Protocols are sets of communication rules for exchange of information. Protocols define speeds and modes for connecting one computer with another.
Common network protocols include:
• 3 layer logical model
• TCP/IP (Transmission Control Protocol / Internet Protocol.
• ISO/OSI model (International Organizations for Standards/ Open System Interconnection)
DATA COMMUNICATION
An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication.[1] An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there."[2]
The designers of the Internet Protocol defined an IP address as a 32-bit number[1] and this system, known as Internet Protocol Version 4 (IPv4), is still in use today. However, due to the enormous growth of the Internet and the predicted depletion of available addresses a new addressing system (IPv6), using 128 bits for the address, was developed in 1995,[3] standardized as RFC 2460 in 1998,[4] and is being deployed worldwide since the mid-2000s.
IP addresses are binary numbers, but they are usually stored in text files and displayed in human-readable notations, such as 172.16.254.1 (for IPv4), and 2001:db8:0:1234:0:567:8:1 (for IPv6).
Application of computer networks
Connectivity is the ability and means to connect a microcomputer by telephone or other telecommunication links to other computers and information sources around the world. The connectivity options that make communication available to end-users include:
• Fax machines (Facsimile transmission machines)
• E-Mail (Electronic Mail)
• Voice messaging systems
• Video conferencing systems
• Shared resources
• Online services
FAX MACHINE
Fax machines convert images to signals that can be sent over a telephone line to a receiving machine. They are extremely popular in offices. They can scan the image of a document and print the image on a paper. Microcomputers use fax/ modem circuit boards to send and receive fax messages.
E-MAIL (Electronic Mail)
Email is a method of sending an electronic message between individuals or computers. One can receive e-mail messages even when one is not on the computer. E-mail messages can contain text, graphics
VOICE MESSAGING SYSTEMS
Voice messaging systems are computer systems linked to telephones that convert human voice into digital bits. They resemble conventional answering machines and electronic mail systems. They can receive large numbers of incoming calls and route them to appropriate ‘voice mailboxes’ which are recorded voice messages. They can forward calls and deliver the same message to many people.
VIDEO CONFERENCING SYSTEMS
Video conferencing systems are computer systems that allow people located at various geographic locations to have in-person meetings. They can use specially equipped videoconferencing rooms to hold meetings. Desktop video conferencing systems use microcomputers equipped with inexpensive video cameras and microphones that sit atop a computer monitor.
SHARED RESOURCES
Shared resources are communication networks that permit microcomputers to share expensive hardware such as laser printers, chain printers, disk packs and magnetic tape storage. Several microcomputers linked in a network make shared resources possible. The connectivity capabilities of shared resources provide the ability to share data located on a computer.
ONLINE SERVICES
Online services are business services offered specifically for microcomputer users. Well-known service providers are America Online (AOL),WorldNet, CompuServe, Africa Online, Kenyaweb, UUNET, Wananchi Online and Microsoft Network.
Typical online services offered by these providers are:
Teleshopping – a database which lists prices and description of services. You place an order, charge the purchase to a credit card and merchandise is delivered by a delivery service.
Home banking – banks offer this service so you can use microcomputers to pay bills, make loan payments, or transfer money between accounts.
Investing – investment firms offer this service so you can access current prices of stocks and bonds. You can also buy and sell orders.
Travel reservations – travel organizations offer this service so you can get information on airline schedules and fare, order tickets, and charge to a credit card.
Internet – You can get access to the World Wide Web.
INTERNET
The internet is a giant worldwide network. The internet was started in 1969 when the United States government funded a major research project on Computer networking called ARPANET (Advanced Research Project Agency NETwork). When on the internet you move through Cyberspace. Cyberspace is the space of electronic movement of ideas and information. The web provides a multimedia interface to resources available on the internet. It is also known as WWW or World Wide Web. The web was first introduced in 1992 at CERN (Centre for European Nuclear Research) in Switzerland. Prior to the web, the internet was all text with no graphics, animation, sound or video.
Common internet applications
Communicating
Communicating on the Internet includes e-mail, discussion groups (newsgroups), and chat groups
You can use email to send or receive messages to people around the world.
Shopping
Shopping on the internet is called e-commerce
You can window shop at cyber malls called storefronts
You can purchase goods using cheques, credit cards or electronic cash called electronic payment.
Researching
You can do research on the internet by visiting virtual libraries and browse through stacks of books.
You can read selected items at the virtual libraries and even check out books.
Entertainment
There are many entertainment sites on the internet such as live concerts, movie previews and book clubs.
You can participate in interactive live games on the internet
How to get connected to the internet
You get connected to the internet through a computer. Using a provider is one of the most common ways users can access the internet. A provider is also called a host computer and is already connected to the internet.
ISPs – Internet Service Providers offer access to the internet for a fee.
URLs (Uniform Resource Locators)
URLs are addresses used by browsers to connect to other resources. URLs have at least two basic parts.
Protocol - used to connect to the resource, HTTP (Hypertext Transfer Protocol) is the most common
Domain name – the name of the server where the resource is located. e.g. yahoo.com
Many URLs have additional parts specifying directory paths, file names, and pointers
Connecting to a URL means that you are connecting to another location called a website.
Moving from one website to another is called Surfing.
Web portals
Web portals are sites that offer a variety of services typically including email, sports updates, financial data, news and links to selected websites. They are designed to encourage you to visit them each time you access the web e.g. MSN, Yahoo etc
Web pages
A web page is a document file sent to your computer when the browser has connected to a website. The document file may be located on a local computer or half-way around the world. The document file is formatted and displayed on your screen as a web page through the interpretation of special command codes embedded in the document called HTML (Hypertext markup Language)
Typically the first web page on a website is referred to as the homepage.
SEARCH TOOLS
Search tools developed for the internet help users locate precise information. To access a search tool, you must visit a website that has a search tool available. There are two basic types of search tool available:
Indexes
Search engines
Search engines
• Search engines are also known as web crawlers or web spiders
• They are organized like a database
• Key words and phrases can be used to search through a database
• Databases are maintained by special programs called agents, spiders or bots
• Widely used search engines are Google, HotBot and AltaVista
E-MAIL(Electronic Mail)
Email is the most common internet activity. It allows you to send messages to anyone in the world who has an internet email account. You need internet and email account to use this type of communication. Two widely used email programs are Microsoft outlook Express and Netscape’s communicator.
Email has three basic elements
i)Header – appears first in an email message and contains the following information.
Address – the address of the person(s) that is to receive the email
Subject – a one line description of the message displayed when a person checks their mail.
Attachment – Files that can be sent by the email program
ii) Message – The text of the email communication
iii) Signature – May include sender’s name, address and telephone number (optional)
Advantages of email
• It is normally much cheaper than using the telephone
• Many different types of data can be transmitted, such as images, documents, speech etc
• It is much faster than the postal service
• Users can filter incoming email easier than incoming telephone calls
• It is normally more secure than the traditional methods
• It is relatively easy to send to groups of people
Disadvantages of email
• It stops people using the telephone
• It cannot be used as a legal document
• Not everyone reads his or her email on a regular basis
• Email messages can be sent on the spur of the moment and may be regretted later on (sending by traditional means allows for a rethink) for extreme cases messages can be sent to the wrong person.
Internets: Intranets and Extranets
An organization may experience two disadvantages in having a connection to the WWW and the internet:
The possible use of the internet for non-useful applications (employees)
The possible connection of non-friendly users from the global connection into the organization’s local network.
For these reasons, many organizations have shied away from connection to the global network and have set up intranets and extranets.
Intranet – a private network without within an organization
Extranet – a private network that connects more than one organization
INTRANETS
Intranets are in-house, tailor-made networks for use within the organization and provide limited access (if any) to outside services and also limit the external traffic (if any) into the intranet. An intranet might have access to the internet but there will be no access from the internet to the organization’s intranet. Intranets centralize their information on central servers which are then accessed by a single browser package. The stored data is normally open and can be viewed by any compatible WWW browser.
Other properties defining an intranet are:
Intranets use browsers, websites, and web pages to resemble the internet within the business
They typically provide internal email, mailing lists, newsgroups and FTP services
These services are accessible only to those within the organization
EXTRANETS
Extranets (external intranets) allow two or more companies to share parts of their intranets related to joint projects. For example two companies may be working on a common project, an extranet would allow them to share files related with project.
Extranets allow other organizations, such as suppliers, limited access to the organization’s network. The purpose of extranet is to increase efficiency and to reduce costs.
Firewalls
A firewall (security gateway) is a security system designed to protect organizational networks. It protects a network against intrusion from outside sources. It includes a special computer called a proxy server, which acts as a gate keeper.
Blogs – Are informal yet structured websites where subscribing individuals can publish stories, opinions, and links to other websites of interest.
Rich Site Summary or Really Simple Syndication (RSS) – Is a simple way for people to have content they want pulled from websites and fed automatically to their computer, where it can be stored for later viewing. Its commonly used with blogs.
Wikis – are collaborative websites where visitors can add, delete, or modify content on the site, including work of previous authors.
Monday, April 18, 2011
ICT -Module 1 Term 1 exam solutions
QUESTION 1 (30 Marks)
1.The functional components of a computer system are: (8 Marks)
a)Input
b)Central Processing Unit
c)Storage
d)Output
By the use of a well labeled diagram, show the electronic components of a computer
2. Briefly describe the function of the Main Memory unit in a CPU (3 Marks)
Main Memory refers to physical memory that is internal to the computer. The word main is used to distinguish it from external mass storage devices such as disk drives. Another term for main memory is RAM.
The computer can manipulate only data that is in main memory. Therefore, every program you execute and every file you access must be copied from a storage device into main memory. The amount of main memory on a computer is crucial because it determines how many programs can be executed at one time and how much data can be readily available to a program.
3.List down AND explain the purpose of the following registers (4 Mks)
a)Memory Address register
The Memory Address Register (MAR) is a CPU register that either stores the memory address from which data will be fetched to the CPU or the address to which data will be sent and stored.
In other words, MAR holds the memory location of data that needs to be accessed. When reading from memory, data addressed by MAR is fed into the MDR (memory data register) and then used by the CPU. When writing to memory, the CPU writes data from MDR to the memory location whose address is stored in MAR.
They store memory addresses which tell the CPU where in memory an instruction is located.
b)Instruction register
instruction register is the part of a CPU's control unit that stores the instruction currently being executed or decoded. In simple processors each instruction to be executed is loaded into the instruction register which holds it while it is decoded, prepared and ultimately executed, which can take several steps.
A hardware element that receives and holds an instruction as it is extracted from memory; the register either contains or is connected to circuits that interpret the instruction (or discover its meaning). Also known as current-instruction register.
4.List down three buses found in a System Unit
Address bus - ( also Memory bus)Transport memory addresses which the processor wants to access in order to read or write.It is a unidirectional bus.
Data bus - Transfers the instructions coming from or going to the processor.It is a bidirectional bus.
Control bus - (Also command bus)Transports orders and synchronization signals coming from control unit and traveling to all other hardware components. It also transmits response signals from the hardware. It is a bidirectional bus.
5.State two factors that determine the computers’ operating speed (2 Marks)
RAM Capacity - The more RAM capacities the faster the operation. RAM (Read Only Memory) hold data and instructions while the computer is running making it easier for the computer to access data and instructions required at hand. The CPU does not have to wait alot for data transfer.
Data bus width - The wider the width the faster the operation.Computers that have 64 bit(bus width) are faster in operation as compared to computers that have 34 bit processors.
Clock speed - Measure of how many instructions the processor can execute in one second.( Measured in Megahertz or Gigahertz) The quicker the rate faster the operation of a computer.
6.Explain two main branches of software (4 Marks)
System softaware
System software consists of programmes that coordinates the activities of hardware and other programs. System software is designed for a specific CPU and hardware class. The combination of a particular hardware configuration and operating system is called a computer platform. These programmes manage the “behind the scenes” operation of the computer.
Examples
§ Operating systems - This are programs that manages the computer resources.
§ Utility Programmes - Utility programmes often come installed in computer systems or packaged with operating systems. Utilities can also be purchased individually. Utility programmes perform useful tasks, such as virus detection, tracking computer jobs and compressing data.
§ Language processors – Compilers and interpreters
Application software
Application software is computer software designed to help the user perform singular or multiple related specific tasks.
These are special written programs to perform specific tasks in real life.Application software refers to any program designed to be carried out by a computer to satisfy a user's specific need.As the name suggests 'Application' this type of software is limited by application. For example the software we use for drawing cannot be used for our calculations and vise versa.
Examples include enterprise software, accounting software, office suites, graphics software and media players,spreadsheets,Word Processors,Presentation,Database amongst others. Many application programs deal principally with documents.
7.Suppose you are provided with a computer system and asked to carry out the following tasks, indicate which program(s) or application programs you are going to use to accomplish each task. (6 Marks)
a)Typing a memo - Microsoft Word, Word Star, Word Perfect
b)Preparing advertisements - Microsoft PowerPoint
c)Creating tables,queries,forms and reports -Microsoft Access,Oracle,Dbase,FoxPro
d)E-mailing - Internet Explorer, Mozilla Firefox, Opera mini
e)Installing a brand new computer - Windows XP, Windows 7, Linux
f)Designing menus - Microsoft Publisher
QUESTION 2 (40 Marks)
1.List two advantages and two disadvantages of computers (2 Marks)
Advantages
Speedy processing
Accuracy and reliability
Compact storage
Secrecy
Versatility - Can do the same thing over and over without being worn out.
Consistency - Gives the same results given the same instructions
Disadvantages
They are expensive to buy
Cuts down employment - leads to unemployment
Needs technical know how to operate
Health hazard -eye problems, backaches etc
Define: (10 Marks)
a)BIT - The smallest and the most fundamental unit of data storage. Usually 0,s and 1,s.
b)Byte - A combination of eight bits
c)Bus - Communication channels found in the system unit of a computer to enhance communication between components of a computer.Also, paths between the components of a computer located on the motherboard to enhance communication in the CPU.
d)Software - Software is detailed step-by-step sequence of instructions which guide computer hardware.
e)Program - Sets of instructions designed and directed towards performing a particular task.
f)Icon - Graphical representations of computer programs.
g)Operating System -This are programs that manages the computer resources.
h)Register - Additional temporary storage locations that are on the CPU itself.The registers are controlled by the control unit and are used to hold and transfer data and instructions, and perform the logical and arithmetic operations.
i)Virus - These are programs that are designed with an ill motive by a malicious,mischievous individual with an intention of causing harm to your computer.
j)RAM - Temporary memory location within the CPU that holds data and instructions while the computer programs are running. It is a volatile memory and must be powered whenever in use.
2.Describe at least four types of operating systems outlining examples of each
(8Marks)
1.Real-time operating systems (RTOS)
Used to control machinery, scientific instruments, and industrial systems. In general, the user does not have much control over the functions performed by the RTOS. Examples of real-time operating systems are Chimera, Lynx, MTOS, QNX, RTMX, RTX, and VxWorks
2.Single-user, single task operating systems
Allow one user to do one thing at a time. And example of a single-user, single task operating system is the operating system used by personal digital assistants (PDAs), also known as handheld computers, Ms Dos.
3.Single-user, multi-tasking operating systems
Allow a single user to simultaneously run multiple applications on their computer. This is the type of operating system found on most personal desktop and laptop computers. The Windows (Microsoft) and Macintosh (Apple) platforms are the most popular single-user, multi-tasking operating systems. Example Windows XP,
4.Multi-user operating systems
Allow multiple users to simultaneously use the resources on a single computer. Unix is an example of a multi-user operating system.
3.Give a brief account on how data is represented in (5 Marks) computers
Computers represent information in binary code, written as sequences of 0s and 1s. Each binary digit (or "bit") may be stored by any physical system that can be in either of two stable states, to represent 0 and 1. Such a system is called bistable. This could be an on-off switch, an electrical capacitor that can store or lose a charge, a magnet with its polarity up or down, or a surface that can have a pit or not. Today, capacitors and transistors, functioning as tiny electrical switches, are used for temporary storage, and either disks or tape with a magnetic coating, or plastic discs with patterns of pits are used for long-term storage.
It takes a certain number of bits to make one byte (normally eight), and when bytes are grouped together at a single address they make up a word in the computer's memory. When data is recorded on some type of magnetic storage medium, such as disk or tape, it is normally organized by bits, characters (bytes), fields, records, and files.
4. Classify computers according to their processing mode and briefly describe on each ( 3 Marks)
Analog Computers - computers that uses the continuously-changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved.Process continuous data. i.e representation of temperature
Digital computers -computers that perform calculations and logical operations with quantities represented as digits, usually in the binary number system. 0s and 1s.Process discrete data.
Hybrid computers - Computers that are capable of processing both the discrete data and continuous data. They combine analog and digital technology for data processing.
1.The functional components of a computer system are: (8 Marks)
a)Input
b)Central Processing Unit
c)Storage
d)Output
By the use of a well labeled diagram, show the electronic components of a computer
2. Briefly describe the function of the Main Memory unit in a CPU (3 Marks)
Main Memory refers to physical memory that is internal to the computer. The word main is used to distinguish it from external mass storage devices such as disk drives. Another term for main memory is RAM.
The computer can manipulate only data that is in main memory. Therefore, every program you execute and every file you access must be copied from a storage device into main memory. The amount of main memory on a computer is crucial because it determines how many programs can be executed at one time and how much data can be readily available to a program.
3.List down AND explain the purpose of the following registers (4 Mks)
a)Memory Address register
The Memory Address Register (MAR) is a CPU register that either stores the memory address from which data will be fetched to the CPU or the address to which data will be sent and stored.
In other words, MAR holds the memory location of data that needs to be accessed. When reading from memory, data addressed by MAR is fed into the MDR (memory data register) and then used by the CPU. When writing to memory, the CPU writes data from MDR to the memory location whose address is stored in MAR.
They store memory addresses which tell the CPU where in memory an instruction is located.
b)Instruction register
instruction register is the part of a CPU's control unit that stores the instruction currently being executed or decoded. In simple processors each instruction to be executed is loaded into the instruction register which holds it while it is decoded, prepared and ultimately executed, which can take several steps.
A hardware element that receives and holds an instruction as it is extracted from memory; the register either contains or is connected to circuits that interpret the instruction (or discover its meaning). Also known as current-instruction register.
4.List down three buses found in a System Unit
Address bus - ( also Memory bus)Transport memory addresses which the processor wants to access in order to read or write.It is a unidirectional bus.
Data bus - Transfers the instructions coming from or going to the processor.It is a bidirectional bus.
Control bus - (Also command bus)Transports orders and synchronization signals coming from control unit and traveling to all other hardware components. It also transmits response signals from the hardware. It is a bidirectional bus.
5.State two factors that determine the computers’ operating speed (2 Marks)
RAM Capacity - The more RAM capacities the faster the operation. RAM (Read Only Memory) hold data and instructions while the computer is running making it easier for the computer to access data and instructions required at hand. The CPU does not have to wait alot for data transfer.
Data bus width - The wider the width the faster the operation.Computers that have 64 bit(bus width) are faster in operation as compared to computers that have 34 bit processors.
Clock speed - Measure of how many instructions the processor can execute in one second.( Measured in Megahertz or Gigahertz) The quicker the rate faster the operation of a computer.
6.Explain two main branches of software (4 Marks)
System softaware
System software consists of programmes that coordinates the activities of hardware and other programs. System software is designed for a specific CPU and hardware class. The combination of a particular hardware configuration and operating system is called a computer platform. These programmes manage the “behind the scenes” operation of the computer.
Examples
§ Operating systems - This are programs that manages the computer resources.
§ Utility Programmes - Utility programmes often come installed in computer systems or packaged with operating systems. Utilities can also be purchased individually. Utility programmes perform useful tasks, such as virus detection, tracking computer jobs and compressing data.
§ Language processors – Compilers and interpreters
Application software
Application software is computer software designed to help the user perform singular or multiple related specific tasks.
These are special written programs to perform specific tasks in real life.Application software refers to any program designed to be carried out by a computer to satisfy a user's specific need.As the name suggests 'Application' this type of software is limited by application. For example the software we use for drawing cannot be used for our calculations and vise versa.
Examples include enterprise software, accounting software, office suites, graphics software and media players,spreadsheets,Word Processors,Presentation,Database amongst others. Many application programs deal principally with documents.
7.Suppose you are provided with a computer system and asked to carry out the following tasks, indicate which program(s) or application programs you are going to use to accomplish each task. (6 Marks)
a)Typing a memo - Microsoft Word, Word Star, Word Perfect
b)Preparing advertisements - Microsoft PowerPoint
c)Creating tables,queries,forms and reports -Microsoft Access,Oracle,Dbase,FoxPro
d)E-mailing - Internet Explorer, Mozilla Firefox, Opera mini
e)Installing a brand new computer - Windows XP, Windows 7, Linux
f)Designing menus - Microsoft Publisher
QUESTION 2 (40 Marks)
1.List two advantages and two disadvantages of computers (2 Marks)
Advantages
Speedy processing
Accuracy and reliability
Compact storage
Secrecy
Versatility - Can do the same thing over and over without being worn out.
Consistency - Gives the same results given the same instructions
Disadvantages
They are expensive to buy
Cuts down employment - leads to unemployment
Needs technical know how to operate
Health hazard -eye problems, backaches etc
Define: (10 Marks)
a)BIT - The smallest and the most fundamental unit of data storage. Usually 0,s and 1,s.
b)Byte - A combination of eight bits
c)Bus - Communication channels found in the system unit of a computer to enhance communication between components of a computer.Also, paths between the components of a computer located on the motherboard to enhance communication in the CPU.
d)Software - Software is detailed step-by-step sequence of instructions which guide computer hardware.
e)Program - Sets of instructions designed and directed towards performing a particular task.
f)Icon - Graphical representations of computer programs.
g)Operating System -This are programs that manages the computer resources.
h)Register - Additional temporary storage locations that are on the CPU itself.The registers are controlled by the control unit and are used to hold and transfer data and instructions, and perform the logical and arithmetic operations.
i)Virus - These are programs that are designed with an ill motive by a malicious,mischievous individual with an intention of causing harm to your computer.
j)RAM - Temporary memory location within the CPU that holds data and instructions while the computer programs are running. It is a volatile memory and must be powered whenever in use.
2.Describe at least four types of operating systems outlining examples of each
(8Marks)
1.Real-time operating systems (RTOS)
Used to control machinery, scientific instruments, and industrial systems. In general, the user does not have much control over the functions performed by the RTOS. Examples of real-time operating systems are Chimera, Lynx, MTOS, QNX, RTMX, RTX, and VxWorks
2.Single-user, single task operating systems
Allow one user to do one thing at a time. And example of a single-user, single task operating system is the operating system used by personal digital assistants (PDAs), also known as handheld computers, Ms Dos.
3.Single-user, multi-tasking operating systems
Allow a single user to simultaneously run multiple applications on their computer. This is the type of operating system found on most personal desktop and laptop computers. The Windows (Microsoft) and Macintosh (Apple) platforms are the most popular single-user, multi-tasking operating systems. Example Windows XP,
4.Multi-user operating systems
Allow multiple users to simultaneously use the resources on a single computer. Unix is an example of a multi-user operating system.
3.Give a brief account on how data is represented in (5 Marks) computers
Computers represent information in binary code, written as sequences of 0s and 1s. Each binary digit (or "bit") may be stored by any physical system that can be in either of two stable states, to represent 0 and 1. Such a system is called bistable. This could be an on-off switch, an electrical capacitor that can store or lose a charge, a magnet with its polarity up or down, or a surface that can have a pit or not. Today, capacitors and transistors, functioning as tiny electrical switches, are used for temporary storage, and either disks or tape with a magnetic coating, or plastic discs with patterns of pits are used for long-term storage.
It takes a certain number of bits to make one byte (normally eight), and when bytes are grouped together at a single address they make up a word in the computer's memory. When data is recorded on some type of magnetic storage medium, such as disk or tape, it is normally organized by bits, characters (bytes), fields, records, and files.
4. Classify computers according to their processing mode and briefly describe on each ( 3 Marks)
Analog Computers - computers that uses the continuously-changeable aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to model the problem being solved.Process continuous data. i.e representation of temperature
Digital computers -computers that perform calculations and logical operations with quantities represented as digits, usually in the binary number system. 0s and 1s.Process discrete data.
Hybrid computers - Computers that are capable of processing both the discrete data and continuous data. They combine analog and digital technology for data processing.
Wednesday, March 16, 2011
How Bits and Bytes Work
Both RAM and secondary storage memory capacities are measured in bytes, as are file sizes when you examine them in a file viewer.
You might hear an advertisement that says, "This computer has a 32-bit Pentium processor with 64 megabytes of RAM and 2.1 gigabytes of hard disk space." And many HowStuffWorks articles talk about bytes (for example, How CDs Work). In this article, we will discuss bits and bytes so that you have a complete understanding.
Decimal Numbers
The easiest way to understand bits is to compare them to something you know: digits. A digit is a single place that can hold numerical values between 0 and 9. Digits are normally combined together in groups to create larger numbers. For example, 6,357 has four digits. It is understood that in the number 6,357, the 7 is filling the "1s place," while the 5 is filling the 10s place, the 3 is filling the 100s place and the 6 is filling the 1,000s place. So you could express things this way if you wanted to be explicit:
(6 * 1000) + (3 * 100) + (5 * 10) + (7 * 1) = 6000 + 300 + 50 + 7 = 6357
Another way to express it would be to use powers of 10. Assuming that we are going to represent the concept of "raised to the power of" with the "^" symbol (so "10 squared" is written as "10^2"), another way to express it is like this:
(6 * 10^3) + (3 * 10^2) + (5 * 10^1) + (7 * 10^0) = 6000 + 300 + 50 + 7 = 6357
continue reading at...: http://computer.howstuffworks.com/bytes.htm
You might hear an advertisement that says, "This computer has a 32-bit Pentium processor with 64 megabytes of RAM and 2.1 gigabytes of hard disk space." And many HowStuffWorks articles talk about bytes (for example, How CDs Work). In this article, we will discuss bits and bytes so that you have a complete understanding.
Decimal Numbers
The easiest way to understand bits is to compare them to something you know: digits. A digit is a single place that can hold numerical values between 0 and 9. Digits are normally combined together in groups to create larger numbers. For example, 6,357 has four digits. It is understood that in the number 6,357, the 7 is filling the "1s place," while the 5 is filling the 10s place, the 3 is filling the 100s place and the 6 is filling the 1,000s place. So you could express things this way if you wanted to be explicit:
(6 * 1000) + (3 * 100) + (5 * 10) + (7 * 1) = 6000 + 300 + 50 + 7 = 6357
Another way to express it would be to use powers of 10. Assuming that we are going to represent the concept of "raised to the power of" with the "^" symbol (so "10 squared" is written as "10^2"), another way to express it is like this:
(6 * 10^3) + (3 * 10^2) + (5 * 10^1) + (7 * 10^0) = 6000 + 300 + 50 + 7 = 6357
continue reading at...: http://computer.howstuffworks.com/bytes.htm
COMPUTER BUS ARCHITECURE
System Buses
The components inside your computer communicate to each other in various different ways. Most of the internal system components, including the processor, cache, memory, expansion cards and storage devices, communicate to each other over one or more "buses".
A bus, in computer terms, is simply a channel over which information flows between two or more devices (technically, a bus with only two devices on it is considered by some a "port" instead of a bus). A bus normally has access points, or places into which a device can tap to become part of the bus, and devices on the bus can send to, and receive information from, other devices. The bus concept is rather common, both inside the PC and outside in the real world as well. In fact, your home telephone wiring is a bus: information flows through the wiring that goes through your house, and you can tap into the "bus" by installing a phone jack, plugging in the phone and picking it up. All the phones can share the "information" (voice) on the bus.
This whole section focuses specifically on the system I/O (input/output) buses, also called expansion buses. First the buses and their characteristics are discussed, and then the most common types of I/O buses found on the PC are described with details on their features.
FOREGROUND READING
FOLLOW THE FOLLOWING LINK: http://www.pcguide.com/ref/mbsys/buses/
The components inside your computer communicate to each other in various different ways. Most of the internal system components, including the processor, cache, memory, expansion cards and storage devices, communicate to each other over one or more "buses".
A bus, in computer terms, is simply a channel over which information flows between two or more devices (technically, a bus with only two devices on it is considered by some a "port" instead of a bus). A bus normally has access points, or places into which a device can tap to become part of the bus, and devices on the bus can send to, and receive information from, other devices. The bus concept is rather common, both inside the PC and outside in the real world as well. In fact, your home telephone wiring is a bus: information flows through the wiring that goes through your house, and you can tap into the "bus" by installing a phone jack, plugging in the phone and picking it up. All the phones can share the "information" (voice) on the bus.
This whole section focuses specifically on the system I/O (input/output) buses, also called expansion buses. First the buses and their characteristics are discussed, and then the most common types of I/O buses found on the PC are described with details on their features.
FOREGROUND READING
FOLLOW THE FOLLOWING LINK: http://www.pcguide.com/ref/mbsys/buses/
Sunday, February 13, 2011
Software
Software is detailed step-by-step sequence of instructions known as programme which guide computer hardware.
A computer programme is a sequence of instructions that tell the computer hardware what to do. Programmes are written in (programming) languages, which consist of a set of symbols combined according to a given syntax.
A programme must be in main memory (RAM) to be executed. These invisible, intangible
components of a computer that direct and control the operations of the hardware when processing data are referred to as software.
Software is classified into two major types: System and Application software.
System software
System software consists of programmes that coordinates the activities of hardware and other programs. System software is designed for a specific CPU and hardware class. The combination of a particular hardware configuration and operating system is called a computer platform. These programmes manage the “behind the scenes” operation of the computer.
Examples
§ Operating systems - This are programs that manages the computer resources.
§ Utility Programmes - Utility programmes often come installed in computer systems or packaged with operating systems. Utilities can also be purchased individually. Utility programmes perform useful tasks, such as virus detection, tracking computer jobs and compressing data.
§ Language processors – Compilers and interpreters
OPERATING SYSTEMS
The functions of an operating system include:
§ Performing common hardware functions
- Accepting input and store data on disks and send data to output devices
§ Providing a user interface
§ Providing hardware independence
§ Managing system memory
§ Managing processing
§ Controlling access to system resources
- Protection against unauthorised access
- Logins and passwords
§ Managing files
- Physical storage location
- File permissions
- File access
Examples of operating systems include:
• DOS – Disk Operating System
• Windows 3.1, 95, 98, NT, 2000, ME,7, XP
• Linux, Unix, MAC OS, System/7
Application software
Applications software include programmes designed to help end users solve particular problems using the computer or to perform specific tasks.
Application software could either be Proprietery or off- the- shelf software.
Proprietary Software
Is a computer software which is legal property of one party. The terms of use for other parties is defined by contracts or licensing agreements.
Advantages of proprietary software
§ You can get exactly what you need in terms of reports, features etc.
§ Being involved in development offers a further level in control over results.
§ There is more flexibility in making modifications that may be required to counteract a new initiative by a competitor or to meet new supplier or customer requirements. A merger with another firm or an acquisition will also necessitate software changes to meet new business needs.
Disadvantages of proprietary software
It can take a long time and significant resources to develop required features.
Inhouse system development staff may become hard pressed to provide the
required level of ongoing support and maintenance because of pressure to get Application Software.
Off-the-Shelf Software
Off-the-shelf is a term for software or hardware, generally technology or computer products that are ready-made and available for sale, lease or license to the general public.
Advantages of off-the-shelf software
§ The initial cost is lower since the software firm is able to spread the development costs over a large number of customers.
§ There is lower risk that the software will fail to meet the basic business needs
§ You can analyse existing features and performance of the package
§ Package is likely to be of high quality since many customer firms have tested the software and helped identify many of its bugs.
Disadvantages of off-the-shelf software
§ An organisation may have to pay for features that are not required or never used.
§ The software may lack important features, thus requiring future modifications or customisation. This can be very expensive because users must adopt future releases of the software.
§ Software may not match current work processes and data standards.
Application software is further classified into general-purpose software and applications which include:
§ Word processing – Create, edit and print text documents, e.g. MS Word and Word Perfect.
§ Spreadsheets – Provide a wide range of built-in functions for statistical, logical, financial,database, graphics, data and time calculations, e.g. Lotus 1-2-3, Excel and QuattroPro.
§ Database management systems (DBMS) – Store, manipulate and retrieve data. e.g.Access, FoxPro and dBase.
§ Online Information Services – Obtain a broad range of information from commercial services. e.g. America Online and CompuServe
§ Communications - Ms Outlook for email
§ Browsers e.g Internet Explorer, Mozilla Firefox and Eudora
§ Graphics – Develop graphs, illustrations and drawings. e.g. PaintShop, FreeHand and Corel
§ Project Management – Plan, schedule, allocate and control people and resources
needed to complete a project according to schedule. e.g. Project for Windows and Time Line, Ms Project.
§ Financial Management – Provide income and expense tracking and reporting to monitor and plan budgets, e.g. Quicken,Quickbooks, Sage, Pastel
§ Desktop publishing - used to create high-quality printed output including text and graphics; various styles of pages can be laid out; art and text from other programmes can also be integrated into published pages, e.g. PageMaker and Publisher.
§ Presentation packages like MS PowerPoint
Note: A software suite, such as Microsoft Office, offers a collection of powerful programmes including word processing, spreadsheet, database, graphics among others. The programmes in a software suite are designed to be used together. In addition, the commands, t icons and procedures are the same for all programmes
Software is detailed step-by-step sequence of instructions known as programme which guide computer hardware.
A computer programme is a sequence of instructions that tell the computer hardware what to do. Programmes are written in (programming) languages, which consist of a set of symbols combined according to a given syntax.
A programme must be in main memory (RAM) to be executed. These invisible, intangible
components of a computer that direct and control the operations of the hardware when processing data are referred to as software.
Software is classified into two major types: System and Application software.
System software
System software consists of programmes that coordinates the activities of hardware and other programs. System software is designed for a specific CPU and hardware class. The combination of a particular hardware configuration and operating system is called a computer platform. These programmes manage the “behind the scenes” operation of the computer.
Examples
§ Operating systems - This are programs that manages the computer resources.
§ Utility Programmes - Utility programmes often come installed in computer systems or packaged with operating systems. Utilities can also be purchased individually. Utility programmes perform useful tasks, such as virus detection, tracking computer jobs and compressing data.
§ Language processors – Compilers and interpreters
OPERATING SYSTEMS
The functions of an operating system include:
§ Performing common hardware functions
- Accepting input and store data on disks and send data to output devices
§ Providing a user interface
§ Providing hardware independence
§ Managing system memory
§ Managing processing
§ Controlling access to system resources
- Protection against unauthorised access
- Logins and passwords
§ Managing files
- Physical storage location
- File permissions
- File access
Examples of operating systems include:
• DOS – Disk Operating System
• Windows 3.1, 95, 98, NT, 2000, ME,7, XP
• Linux, Unix, MAC OS, System/7
Application software
Applications software include programmes designed to help end users solve particular problems using the computer or to perform specific tasks.
Application software could either be Proprietery or off- the- shelf software.
Proprietary Software
Is a computer software which is legal property of one party. The terms of use for other parties is defined by contracts or licensing agreements.
Advantages of proprietary software
§ You can get exactly what you need in terms of reports, features etc.
§ Being involved in development offers a further level in control over results.
§ There is more flexibility in making modifications that may be required to counteract a new initiative by a competitor or to meet new supplier or customer requirements. A merger with another firm or an acquisition will also necessitate software changes to meet new business needs.
Disadvantages of proprietary software
It can take a long time and significant resources to develop required features.
Inhouse system development staff may become hard pressed to provide the
required level of ongoing support and maintenance because of pressure to get Application Software.
Off-the-Shelf Software
Off-the-shelf is a term for software or hardware, generally technology or computer products that are ready-made and available for sale, lease or license to the general public.
Advantages of off-the-shelf software
§ The initial cost is lower since the software firm is able to spread the development costs over a large number of customers.
§ There is lower risk that the software will fail to meet the basic business needs
§ You can analyse existing features and performance of the package
§ Package is likely to be of high quality since many customer firms have tested the software and helped identify many of its bugs.
Disadvantages of off-the-shelf software
§ An organisation may have to pay for features that are not required or never used.
§ The software may lack important features, thus requiring future modifications or customisation. This can be very expensive because users must adopt future releases of the software.
§ Software may not match current work processes and data standards.
Application software is further classified into general-purpose software and applications which include:
§ Word processing – Create, edit and print text documents, e.g. MS Word and Word Perfect.
§ Spreadsheets – Provide a wide range of built-in functions for statistical, logical, financial,database, graphics, data and time calculations, e.g. Lotus 1-2-3, Excel and QuattroPro.
§ Database management systems (DBMS) – Store, manipulate and retrieve data. e.g.Access, FoxPro and dBase.
§ Online Information Services – Obtain a broad range of information from commercial services. e.g. America Online and CompuServe
§ Communications - Ms Outlook for email
§ Browsers e.g Internet Explorer, Mozilla Firefox and Eudora
§ Graphics – Develop graphs, illustrations and drawings. e.g. PaintShop, FreeHand and Corel
§ Project Management – Plan, schedule, allocate and control people and resources
needed to complete a project according to schedule. e.g. Project for Windows and Time Line, Ms Project.
§ Financial Management – Provide income and expense tracking and reporting to monitor and plan budgets, e.g. Quicken,Quickbooks, Sage, Pastel
§ Desktop publishing - used to create high-quality printed output including text and graphics; various styles of pages can be laid out; art and text from other programmes can also be integrated into published pages, e.g. PageMaker and Publisher.
§ Presentation packages like MS PowerPoint
Note: A software suite, such as Microsoft Office, offers a collection of powerful programmes including word processing, spreadsheet, database, graphics among others. The programmes in a software suite are designed to be used together. In addition, the commands, t icons and procedures are the same for all programmes
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