Архитектура Аудит Военная наука Иностранные языки Медицина Металлургия Метрология
Образование Политология Производство Психология Стандартизация Технологии
The methods of mailing lists
1. A ............................. is a discussion forum where participants subscribe to a list and receive messages via e-mail.
2. In a discussion list you receive the messages directly into your ............................ .
3. In a newsgroup, however, you read the articles that are stored in one .............................. .
4. To receive messages from a mailing list, first you need to ............................... to it.
5. Some lists may be ............................ to certain professionals, requiring specific qualifications to join them.
6. Each list has two addresses: (i) ......................................, and (ii) ............................. .
7. Mailing lists usually have a FAQ file. FAQ is an acronym for ..................................................... .
What is a mailing list?
1. A...................... mailing lists are controlled by a special computer program.
2. The process of subscribing adds your e ................... address to the list.
3. A d ....................... is a type of list that groups individual messages together and sends them periodically as one message.
4. In newsgroups, the messages posted by contributors are called "a ............................" .
5. Insulting or insensitive messages directed at each other in a discussion forum are known as f................... .
6. New participants in discussion forums are also called "n ..................".
7. If you want to get off a mailing list, you just type the command u.............................. followed by the name of the list.
8. The lists a ....................... by a human moderator usually have the word "-request" in the address.
Infotech: English For Computer Users Cambridge University Press
UNIT 2.SCIENCE AND TECHNOLOGY
1. As more and more of us are linked by . . . , how soon will it be before the paperless office becomes a reality?
2. This new technique is a . . . in the treatment of cancer.
3. The dishwasher and other . . . have helped to relieve the boredom of domestic chores.
4. Satellite technology can help to . . . for extraction from the earth.
5. The Model T Ford was the first . . . car in the world.
6. It is difficult for some people to . . . the speed of change in the modern world.
7. The police have access to a vast . . . which helps them in their fight against crime.
8. We need . . . to prevent all the information stored on computers from being misused.
9. Many . . . which people found boring and tiring can now be carried out by machines.
10. Many employees have been . . . as a result of the introduction of new technology.
11. Nuclear power stations have computer-controlled systems to . . . their reactors and prevent accidents.
12. This car comes with such . . . as a collapsible steering column and a driver’s airbag.
13. A power station capable of producing electricity from waves is currently . . .
14. With the advance in . . . we may be able to create a race of “perfect” human beings one day, or is that just science fiction?
15. The increase in . . . has led to problems such as how to pay for the care of the elderly.
16. Many technological developments which have greatly affected the way we live are nowadays . . . by the younger generation.
First Certificate Organiser
The problems of inventors
1. Read the text and do the tasks following it.
Many of the modern world's most famous discoveries and inventions were not made by scientists, but by amateur inventors. Often, these inventors had such unusual ideas that they were laughed at. But people like these, working on their own, gave us many of the things we use every day.
Clarence "Bob" Birdseye, who invented frozen foods, was both a successful inventor and a good businessman-. But it took him years to overcome the biggest problem of successful inventions -convincing people to try something new and different. Birdseye first tried to freeze fish. After years of experimenting with the process, he started Birdseye. Seafoods, Inc. But the company soon went bankrupt. Even though the process worked, people didn't believe that frozen fish could possibly be good. It took a long time, but people finally accepted frozen food. By the end of his life, Birdseye, who was a completely self-taught inventor, had 100 patents that he sold for a total of 22 million dollars.
Few inventors were as successful as Birdseye. Some, like the original owners of Coca-Cola, didn't realize the potential of their discoveries. The son of the inventor of Coca-Cola sold the recipe for $2,300. Today the product is worth billions of dollars. In 1853, Karl Gerhardt invented aspirin, but he didn't know what to do with it. Fifty years after his invention, a German company discovered that it was a painkiller and has since made millions selling it. Edwin Armstrong invented FM radio, but he spent his whole life trying to protect his invention. Competitors stole his patents, and companies cheated him out of money. Finally, he became so frustrated with his failures that he ended his life by jumping out of a window.
Most great inventors, like Gerhardt and Armstrong, made little or nothing from their inventions. The first person with a new idea may get attention, but he also gets the problem of an untried idea. In business, it is sometimes better to be second.
2. Read the text again and decide whether these statements are true or false. Correct the false ones with the facts from the text.
3. Discuss the following questions in pairs.
How to be a successful inventor
Well, you need good timing for a start. You can have a great idea which the public simply doesn't want ... yet. Take the Italian priest, Giovanni Caselli, who invented the first fax machine using an enormous pendulum in the 1860s. Despite the excellent quality of the reproductions, his invention quickly died a commercial death. It was not until the 1980s that the fax became an essential piece of equipment in every office …too late for Signor Caselli. Money also helps. The Frenchman Denis Pap in (1647-1712) had the idea for a steam engine almost a hundred years before the better-remembered Scotsman James Watt was even born ... but he never had enough money to build one.
You also need to be patient (it took scientists nearly eighty years to develop a light bulb which actually worked) ... but not too patient. In the 1870s, Elisha Gray, a professional inventor from Chicago, developed plans for a telephone. Gray saw it as no more than “a beautiful toy”, however. . . When he finally sent details of his invention to the Patent Office on February 14th 1876, it was too late; almost identical designs had arrived just two hours earlier ... and the young man who sent them, Alexander Graham Bell, will always be remembered as the inventor of the telephone.
Of course what you really need is a great idea — but if you haven't got one, a walk in the country and a careful look at nature can help. The Swiss scientist, George de Mestral, had the idea, for Velcro when he found his clothes covered in sticky seed pods after a walk in the country. During a similar walk in the Trench countryside some 250 years earlier, Rene-Antoine Ferchault de Reaumur had the idea that paper could be made from wood when he found an abandoned wasps' nest. You also need good commercial sense. Willy Higginbotham was a scientist doing nuclear research in the Brookhaven National Laboratory in Upton, USA. In 1958 the public were invited to the Laboratory to see their work; but both parents and children were less interested in the complicated equipment and diagrams than in a tiny 120 cm screen with a white dot which could be hit back and forth over a “net” using a button and a knob. Soon hundreds of people were ignoring the other exhibits to play the first ever computer game ― made from a simple, laboratory instrument called an “oscilloscope”. Higinbotham, however, never made a cent from his invention: he thought people were only interested in the game because the other exhibits were so boring!
Cutting Edge Students’ Book
WHY THE LAST SHALL BE FIRST
Have you heard of Berkey or Ampex? Gablinger or Chux? Perhaps you should have, because each occupies an important place in the history of product innovation. Berkey produced the first hand-held electronic calculators, Ampex the first video recorders. Gablinger developed low-alcohol lager and Chux sold the first disposable nappies.
Or perhaps you should not, because none of these companies made a commercial success of their innovations. Today the calculators we use are probably made by Casio, our video recorder comes from Matsushita, our low-alcohol beer is Miller Lite, our nappies are made by Procter & Gamble. In each of these markets the innovator was swept away. Xerox looks like an exception to this sorry catalogue. The company was first into the photocopier market and, even if its dominance was ultimately challenged by Canon, it remains a large and successful company today. But Xerox was also a pioneer in fax machines and personal computers. Each of these eventually proved to be a success ― but not for Xerox Corporation.
As we all know, it was Apple that developed the personal computer market. But Apple's leadership quickly disappeared when IBM came on the scene. Apple then jumped ahead by introducing the graphical user interface. Its windows and mice brought personal computing within the reach of everyone. But it is Microsoft that does this now. The business world is not kind to pioneers. Even if you know how a market will develop, timing is a matter of luck ― or of quite exceptional skill.
There are two closely related lessons. One is that being first is not often very important. The other is that innovation is rarely a source of competitive advantage on its own. Individuals and small companies can make a great deal of money out of good new ideas. The success of large established corporations ― Matsushita, Philip Morris, IBM or General Electric is generally based on other things: their depth of technical expertise, their marketing skills. And time and again these characteristics enable them to develop the innovative concept far more effectively than the innovators themselves. This is not to say that there is no role in business for the great innovator. After all. General Electric was built on the extraordinary creativity of Thomas Edison's mind, the Ford motor company on the abilities of its eponymous founder. The imagination of Walt Disney created a company that is still without parallel or rival. Perhaps Akio Morita of Sony occupies a similar place in the annals of modern business.
Reader on Science and Technology
TECHNOLOGY IN OUR LIVES
operator w register w cashier w scanner w home-owner w miniature
Technology plays a role in all aspects of our lives ― the way we work, and the way we live at home. The speed of technological change in the past 100 years has been incredible.
The early telephones were large, and they didn't even have dials or buttons. You picked up a receiver and talked to an operator who made the call for you. Nowadays, cellular telephones fit in our pockets, and we can use them to make phone calls from anywhere to anywhere. In grocery stores, cashiers used to punch keys on cash registers to enter the price of each item. These days, scanners read bar codes on products packaging, and the prices are recorded by a computerized cash register. In the past, we made a trip to the bank to deposit or withdraw money. Now we can use ATMs (automated teller machines). And many people now do their bank transactions at home online.
Modern technology has dramatically improved our lives. Personal computers enable us to create documents, store information, and analyze data ― at work or at home. The Internet allows us to send and receive e-mail messages, connects us to the World Wide Web, and allows us to go shopping online from our homes. Miniature cameras that patients can swallow permit doctors to diagnose medical conditions without surgery. "Smart homes" operated by computers turn lights on and off as people enter or leave rooms and enable homeowners to "call their houses" to turn on the heat or air conditioning.
Many people feel, however, that technology has its price. With automated supermarket checkout lines, ATMs and online banking, and Internet shopping, we can meet our daily needs without having contact with other people. Life with technology can be very lonely! Also, many people are concerned about privacy. Technology makes it possible for companies or the government to monitor our use of the Internet. Our credit card numbers, bank account information, medical information, and other personal data are all stored on computers. Protecting that information will be an important issue in the years ahead.
Reader on Science and Technology
1. Cellular telephones …..in our pockets.
2. The computerized cash registers … the prices of products.
3. Modern technology has improved our… of living
4. Many people can do their bank …at home on line.
5. Personal computers can… information.
a) Nowadays telephones are large and we are to talk to the operator who makes the call for us.
b) Nowadays, personal computers are great help at home and at work.
c) The Internet has rather limited possibilities today.
d) With the Internet we can meet our daily needs without having contact with other people.
e) Privacy is not the point the users of the Internet are concerned about.
a) What was the way people communicate with each other in the 60s?
b) What were the drawbacks of the early telephones?
c) What jobs can computer do for us? Make a list of jobs.
1. New information you have got from the text.
2. Speak about your experience in using the Internet.
THE MENACE OF THE MICRO
a) The developments in new technologies
b) The threat of new technologies
c) The benefit of new technologies
Hardly a week goes by without some advance in technology that would have seemed incredible 50 years ago. Over the past 20 years computers have completely revolutionized our lives. Yet we can expect the rate of change to accelerate rather than slow down within our lifetimes. The next 25 years will see as many changes as have been witnessed in the past 150.
These developments in technology are bound to have a dramatic effect on the future of work. By 2010, new technology will have revolutionized communications. People will be transmitting messages down telephone lines that previously would have been sent by post. A postal system which has essentially been the same since the Pharaohs will virtually disappear overnight. Once these changes are introduced, not only postmen but also clerks and secretaries will vanish in a paper-free society. All the routine tasks they perform will be carried on a tiny silicon chip. As soon as this technology is available, these people will be as obsolete as the horse and cart after the invention of the motor car. One change will make thousands, if not millions, redundant.
Even people in traditional professions, where expert knowledge has been the key, are unlikely to escape the effects of new technology. Instead of going to a solicitor, you might go to a computer which is programmed with all the most up-to-date legal information. Indeed, you might even come up before a computer judge who would, in all probability, judge your case more fairly than a human counterpart. Doctors, too, will find that an electronic competitor will be able to carry out a much quicker and more accurate diagnosis and recommend more efficient courses of treatment.
In education, teachers will be largely replaced by teaching machines far more knowledgeable than any human being. What's more, most learning will take place in the home via video conferencing. Children will still go to school though, until another place is created where they can make friends and develop social skills through play.
What, you may ask, can we do to avoid the threat of the dole queue? Is there any job that will be safe? First of all, we shouldn't hide our heads in the sand. Unions will try to stop change but they will be fighting a losing battle. People should get computer literate as this just might save them from professional extinction. After all, there will be a few jobs left in law, education and medicine for those few individuals who are capable of writing and programming the software of the future. Strangely enough, there will still be jobs like rubbish collection and cleaning as it is tough to programme tasks which are largely unpredictable.
If we accept that people have the need to work, then an option might well be to introduce compulsory job sharing and to limit the length of the working week. Otherwise, we could find ourselves in an explosive situation where a technocratic elite is both supporting, and threatened by, vast numbers of the unemployed. Whether the future is one of mass unemployment or greater freedom and leisure will depend on how change is managed over this difficult period and how the relationship between work and reward is viewed.
Reader on Science and Technology
Using the information from the article agree or disagree with the statements. Say Yes or No.
____Over the past years new technologies have completely revolutionized our lives.
____Some traditional professions (for example lawyers) will escape the effects of new technologies.
____The new electronic devices will cause the changes in education and medicine.
____Some jobs will still exist as they are difficult to be programmed.
____New technologies will be dangerous for people.
____New technologies will completely replace people in all areas of their lives.
What’s your opinion? Do you think people are right when they say that new technology is “a double edged sword”?
How have science and technology changed our lives? Think about discoveries, inventions, new products, and their effects (good and bad). How will science and technology affect our lives in future?
Scientific and technological breakthroughs have brought great benefits. You only have to look around your own home to see . . .
Many illnesses can now be treated or cured, for example, . . .
Other examples of changes are . . .
Have our lives always been improved, however? Have we become too passive? Are we too dependant on technology? How dangerous could it be?
Take, for example, television/computer games/the Internet . . .
New products have also made a major difference to our working lives.
Nowadays, . . .
In the future there may be even more major breakthroughs in the fields of medicine/leisure/work . . .
We may no longer have to . . ./ We will be able to . . .
First Certificate Organiser
UNIT 3.CAREERS IN IT
Elissa“I’m interested in writing software. My friends say I’m a techno-nerd because I prefer working with computers to people. Money is important but I’d rather do a job I enjoy. I want to take a distance-learning course so I can study at home.”
Katie“I like shopping and I think the future of business is on the Internet. I’m good with computers, but I also like working with people. I’d like to manage my own online company. This will give me a lot of responsibility. E-commerce comes with risks, but rewards are high when you succeed.”
Martin“Many people like Web design, but I think data management gives more job security. There is so much information on the internet, and companies need people who know how to store, manage and retrieve data. I want to get my degree and work for a good company.”
Peter “I’m using Java-script to make my website more interactive. After college, I’d like to try telecommuting. This is working at home, using e-mail to communicate with clients. I want freedom, flexibility and long holidays, which you don’t get by working in an office.”
1. wants to work at home? _____
2. wants a secure job? _____
3. does not want to study at college? _____
4. wants to choose when to work? _____
5. wants to manage people? _____
6. likes working with data? _____
7. wants to be rich and successful? _____
8. uses a coding system for web pages? _____
1. _____ telecommunicating to working in an office.
a) I’d rather
b) I prefer
c) I like
2. _____ to do a distance-learning course.
a) I’d prefer
b) I ‘d rather
c) I don’t like
3. _____ working long hours all the time.
a) I’d prefer
b) I don’t like
c) It’s good
4. _____ to work with computers all day as I think it would be boring..
a) I’d rather not
b) I wouldn’t like
c) I don’t like
5. _____ be a rich techno-nerd than poor and popular.
a) I’d rather
b) I prefer
c) I like
6. _____ in being a secretary. I want a better job.
a) I’m not interested
b) I’m thinking of
c) I don’t like
IT WORKSHOP Oxford University Press
The Rules of the Resume Game
Resume writing is like tennis in that certain rules apply. The tennis court is a specific size. The net is a standard height. You can remove the net and hit the ball, but then you're not playingtennis.Similar conventions apply to resume writing. You can make up your own rules as you go along. For Example, you can print your resume on bright red paper ― and you'll have an eye-catcher all right-but you won't have a decent resume.
Here are the features of the resume that always produces interviews and job offers:
– Here is my resume.
– Well, will you answer some questions?
You graduated from . . . , didn’t you?
You don’t have any work experience, do you?
good at/ what/you/are ?
- Are there any promotion prospects?
- Sure, and there’s a very good training scheme (for your information).
- What about the pay?
- We’re going to pay you . . . .
- What are the working hours?
- From . . . till . . . , five days a week except Saturday and Sunday.
- Do I get dinner free?
- Do I get a company car?
- How long are the holidays?
- There’s a five-week holiday allowance.
Right you are.
It’s a pity!
. . . . , I’m afraid.
IT WORKSHOP Oxford University Press
UNIT 1. BIRTH OF THE NET
Test your knowledge of Internet staff!
256 / 200 /216
Visu Tech/ Netview/ Mosaic
Metal/ plastic/ wood
1993/ 1976/ 1984
Hexadom/ nothing/ hexademical
TCP/P /Ethernet / WWW/ ISP
Internic / W3C / WWW Board
1989 / 1991/1987
Oak/ Latte / Power +
What’s your score?
BIRTH OF THE NET
The Internet has had a relatively brief, but explosive history. It grew out of an experiment begun in the 1960's by the U.S. Department of Defense. The DoD wanted to create a computer network that would continue to function in the event of a disaster, such as a nuclear war. If part of the network was damaged or destroyed, the rest of the system still had to work. That network was ARPANET, which linked U.S. scientific and academic researchers. It was the forerunner of today's Internet.
In 1985, the National Science Foundation (NSF) created NSFNET, a series of networks for research and education communication. Based on ARPANET protocols, the NSFNET created a national backbone service, provided free to any U.S. research and educational institution. At the same time, regional networks were created to link individual institutions with the national backbone service.
NSFNET grew rapidly as people discovered its potential and as new software applications were created to make access easier. Corporations such as Sprint and MCI began to build their own networks that they linked to NSFNET. As commercial firms and other regional network providers have taken over the operation of the major Internet arteries, NSF has withdrawn from the backbone business.
NSF also coordinated a service called InterNIC that registered all addresses on the Internet so that data could be routed to the right system. This service has now been taken over by Network Solutions, Inc. and other registration services in cooperation with NSF.
When the World Wide Web began in 1990, few suspected how successful it would become. There are now millions of websites and billions of web pages. But as many people are well aware, the Web can be painfully slow. Most people still connect to the Internet using 56 Kbps modems and telephone lines. Because the data-carrying capacity of telephone lines, known as bandwidth, can be low, receiving electronic data may take a long time. New technology promises to address this problem.
Connecting to the Internet using fiber optic lines and via cable TV and satellite increases bandwidth dramatically, making the Web more useful. Expect to see an explosion of e-commerce, collaborative projects, videoconferencing and virtual environments. Many of these applications are under development or already in use in some form.
Internet English Website
INTERNET 2 ―THE NEXT STEP
¨ Partners for change
¨ Trials and challenges
¨ A new project
¨ Future plans
¨ Speed, security, service
Internet2 is a collaborative project between universities, government agencies and industry partners in the USA. It aims to create advanced Internet applications for academic research, distance learning and education. The I2 project was developed by the University Corporation for Advanced Internet Development (UCAID) in October 1996.
There are three major challenges facing Internet2:
· to establish an advanced communications infrastructure for the US research and education community
· to develop new applications, such as digital libraries, telemedicine and virtual laboratories, allowing participants to send big packets of data and video at high speed. For Example, teachers and students can view and consult during real-time medical operations, scientists can collaborate in virtual meetings etc
· to transfer the new network capabilities to all levels of education and to the rest of the Internet.
The I2 project is made up of three main categories of members: universities, non-profit organizations and corporate partners, i.e. sponsors and industries interested in investing in the project.
Internet2 is working together with advanced networks such as the high-speed Backbone Network Service developed by MCI/WorldCom, and the Next Generation Internet, which is being built by US federal agencies. It runs on a new fibre-optic backbone called Abilene, which operates at speeds of up to 2.4 gigabits (1,024 megabits) per second. Internet2 uses Internet Protocol version 6 (IPv6) instead of the current IPv4. This new protocol uses the Quality of Service (Quos) technology, which allows users to send data with guaranteed delivery - on time and intact.
Internet 2 and its fast backbones are not available to the general public yet, and its physical structure is not intended to replace the global Internet. But the plan for the future is to integrate the new technology with the public Internet and to make it available to everyone.
provide w develop w use w call w send w deliver
1. The new national backbone ................................ Abilene.
2. The Internet2 project ................................ by UCAID in October 1996.
3. Funds and grants for research ................................ by non-profit organizations like the National Science Foundation.
4. One objective of Internet2 is to develop new technologies that can ................................ in the global Internet.
5. Huge packets of data and video ................................ at high speed.
6. In the future it’s likely that all media (TV, web content, email, etc.) ................................ over Internet2.
In paragraph 1
· investigation undertaken to discover new facts
In paragraph 2
· technology that provides high-quality information to doctors over long distances
In paragraph 4:
· glass material that guides light impulses at high frequencies
· high-speed data highways that connect other networks
· 1,024 megabits
· specification that describes how computers will talk to each other on a network
A NEW KIND OF WEB
While PCs were once the primary means of accessing the Internet, we're now seeing Internet-enabled devices such as pagers and cell phones that send and receive e-mail and access the Web. Soon, everything from your car to your refrigerator will be connected to the global network, communicating with each other wirelessly.
Electrolux, best known for its vacuum cleaners, has developed the ScreenFridge, an Internet icebox that manages your pantry, among other things. It e-mails a shopping list to your local supermarket and coordinates a convenient delivery time with your schedule. Say hello to a brave, new world.
Internet English Website
UNIT 2. SECURITY ISSUES
Criminals in the past used to have guns, masks and escape cars. Now they have a computer, a telephone and a piece of computer equipment called a “modem”. They simply dial a telephone number to link their own computer with others, and then, using a password (a secret word or phrase), enter a company’s computer system (in a bank or a government office for example). Many companies stupidly used to have the word “password” as their password.
In 1990 two American teenagers broke into a computer system and added rude messages to some information and made other important data disappear. The damage cost over two million dollars to correct. A 12-year old boy in Detroit used his own computer to enter the computer system of a large company and caused financial chaos.
In Britain, computer crime costs companies about 400 million pounds a year. Often, the computer criminals do not want to make money; they just want to show the world how clever they are.
They also like to create computer viruses. They program a computer disk with a special fault in it. When a computer copies a disk, the fault enters the computer’s memory. That means it gets onto any other disk each time you put a new disk into your computer. Some viruses are just silly messages. For example, one puts the message “peace and love” on your computer screen while you are working. Other viruses use all the “memory” on the computer, and the computer is “sick” and unable to work. One hospital in Britain recently lost all of its records about sick patients because of a computer virus.
1.Match the words and definitions listed below.
2.Read the article and answer the questions.
1. What is a computer virus?
2. How does a virus work?
3. How can a virus spread?
4. What are the sources of viruses?
5. How can you keep your computer virus-free?
A computer virus ― unwanted program that has entered your system without you knowing about it ― it has two parts, which I’ll call the infector and the detonator. They have two very different jobs. One of the features of a computer virus that separates it from other kinds of computer program is that it replicates itself, so that it can spread (via floppies transported from computer to computer, or networks) to other computers.
After the infector has copied the virus elsewhere, the detonator performs the virus’s main work. Generally, that work is either damaging data on your disks, altering what you see on you computer display, or doing something else that interferes with the normal use of computer.
Here’s an Example of a simple virus, the Lehigh virus. The infector portion of Lehigh replicates by attaching a copy of itself to COMMAND.COM (an important part of DOS), enlarging it by about 1000 bytes.
So let’s say you put a floppy containing COMMAND.COM into an infected PC at your office ― that is, a PC that is running the Lehigh program. The infector portion of Lehigh looks over DOS’s shoulder, monitoring all floppy accesses. The first time you tell the infected PC to access your floppy drive, the Lehigh infector notices the copy of COMMAND.COM on the floppy and adds a copy of itself to that file.
Then you take the floppy home to your PC and boot from the floppy. (In this case, you’ve got to boot from the floppy in order for the virus to take effect, since you may have many copies of COMMAND.COM on your hard and floppy disks, but DOS only uses the COMMAND.COM on the boot drive.)
Now the virus has silently been installed in your PC’s memory. Every time you access a hard disk subdirectory or a floppy disk containing COMMAND.COM will be used on a boot disk on some computer someday.
Meanwhile, Lehigh keeps a count of infections. Once it has infected four copies of COMMAND.COM, the detonator is trigged. The detonator in Lehigh is a simple one. It erases a vital part of your hard disk, making the files on that part of the disk no longer accessible. You grumble and set about rebuilding your work, unaware that Lehigh is waiting to infect other unsuspecting computers if you boot from one of those four infected floppies.
Don’t worry too much about viruses. You may never see one. There are just a few ways to become infected that you should be aware of. The sources seem to be service people, pirated games, putting floppies in publicly available PCs without write-protect tabs, commercial software (rarely), and software distributed over computer bulletin board systems (also quite rarely, despite media misinformation).
Many viruses have spread through pirated ― illegally copied or broken ― games. This is easy to avoid. Pay for your games, fair and square.
If you use a shared PC or a PC that has public access, such as one in a college PC lab or a library, be very careful about putting floppies into that PC’s drives without a write-protect tab. Carry a virus-checking program and scan the PC before letting it write data onto floppies.
Despite the low incidence of actual viruses, it can’t hurt to run a virus checking program now and then. There are actually two kinds of antivirus programs: virus shields, which detect viruses as they are infecting your PC, and virus scanners, which detect viruses once they’ve infected you. Viruses are something to worry about, but not a lot. A little common sense and the occasional virus scan will keep your virus-free. Remember these four points:
§ Viruses can’t infect a data or text file.
§ Before running an antivirus program, be sure to cold-boot from a write-protected floppy.
§ Don’t boot from floppies except reliable DOS disks or your original production disks.
§ Stay away from pirated software.
3. Decide whether the following statements are true (T) or false (F) in relation to the information in the text. If you feel a statement is false, change it to make it true.
a) Viruses cannot be spread through a computer network, only via floppies transported
from computer to computer.
b) The virus will spread as soon as you put the infected floppy in your PC.
c) The infector works by interfering in some way with the normal use of your computer.
d) The detonator in Lehigh works by altering what you see on your screen.
e) Most viruses spread through pirated games.
f) You should run an antivirus program every time you use your computer
g) There are not very many viruses in circulation
h) Virus shields are more effective than virus scanners.
4. Indicate the line reference where the following ideas are found in the text.
1. L. __ The Lehigh virus must infect four copies of COMMAND.COM before damage is done to data.
2. L. __ Always boot your computer from dependable DOS disks or your original disk.
3. L. __ The infector part of a virus must first copy itself somewhere before the detonator part damages the data on your disks.
4. L. __ Virus scanners discover viruses after the infection and virus shields discover viruses during the infection process.
5. These are answers to questions about the text. Write the questions.
1. Two. one that infects and one that does the damage.
2. By interfering in some way with the normal use of the computer.
3. After it has infected four copies of COMMAND.COM.
4. Every time you access a hard disk subdirectory or a floppy disk containing
5. Yes, by using your common sense and by occasionally scanning for them.
6. Look back in the text and find words or phrases with a similar meaning to:
7.Look back in the text and find words or phrases that have an opposite meaning to:
b) removed from
Oxford English for Computing
COMPUTER VIRUS CLASSIFICATION
Viruses can be divided into classes according to the following characteristics:
Not to forget: there exist also other "harmful" programs or so called "malware", such as Trojan horses. According to the ENVIRONMENT viruses can be divided into:
File viruses either infect executables in various ways (parasitic - the most common type of viruses), or create file doubles (companion viruses), or use filesystem specific features (link viruses).
Boot viruses either save themselves in disk boot sector, or to the Master Boot Record, or change the pointer to an active boot sector.
Macro viruses infect document files, electronic spreadsheets and databases of several popular software packages.
Network viruses use protocols and commands of computer network or e-mail to spread themselves.
There's is a large number of combinations ― for example file-boot viruses infecting both files and boot sectors on disks. As a rule these viruses have rather complicated algorithms of work, often use unusual methods of intrusion into the system, use Stealth and polymorphic technologies. Another Example of the combo ― network macro-virus, not only infecting the documents which are being edited, but also sending copies of itself by email.
The target OPERATING SYSTEM (namely the OS specific objects prone to attack) is the second level of division of viruses into classes. Each file or network virus infects files of one particular or several OS - DOS, Windows 3.xx, Windows95/NT, OS/2 etc. Macro viruses infect the Word, Excel, Office97 format files. Boot viruses are also format oriented, each attacking one particular format of system data in boot sectors of disks.
Among OPERATING ALGORITHMS the following features stand out:
A TSR virus while infecting a computer leaves its resident part in RAM, which then intercepts system calls to target objects and incorporates into them. Resident viruses reside in memory and are active until power down or until operating system reboot. Nonresident viruses do not infect computer memory and are active for an limited time only. Some viruses leave small resident parts in RAM which do not spread the virus. such viruses are considered nonresident.
Macro viruses can also be considered residents, because they reside in computer memory during all the run time of the infected editor program. Here the editor plays the role of operating system, and "system reboot" means the editor program termination.
In multitasking operating systems the lifetime of a resident DOS virus can also be limited by the moment of closing of the infected DOS window, the activity of boot viruses in some operating systems is limited to the moment of installation of OS disk drivers.
The use of Stealth algorithms allows viruses to completely or partially cover their traces inside the OS. The most common stealth algorithm is interception of OS read/write calls to infected objects. In such cases stealth viruses either temporarily cure them, or "substitute" themselves with uninfected pieces of information. In case of macro viruses the most popular technique is to disable the ViewMacro menu(s). "Frodo" is one of the first file Stealth viruses; "Brain" is the first boot Stealth virus.
SELF-ENCRYPTING and POLYMORPHIC capabilities are used by virtually all kinds of viruses to make virus detection procedure as complicated as possible. Polymorphic viruses are really hard to detect; they have no signatures, that is none of their code fragments remain unchanged. In most cases two samples of the polymorphic virus will not have a single match when doing a byte compare. This may be achieved by encrypting of the main body of the virus and making modifications to the decryption routine.
A variety of NONSTANDARD TECHNIQUES are being used in viruses to hide themselves as deep as possible in the OS kernel (as in "3APA3A"), to protect its residents copy from being detected ("TPVO", "Trout2"), make curing more difficult (for Example placing its copy into Flash BIOS) etc..
On their DESTRUCTIVE CAPABILITIES viruses can be divided as follows:
But even if no destructive branches can be found in the algorithm of a virus, one cannot be perfectly sure that this virus is harmless, because its infiltration into a computer may prove to be unpredictable and sometimes have catastrophic consequences. This is due to the fact that any virus like any program may contain errors, which may damage both files and disk sectors (for Example, seemingly harmless "DenZuk" virus works rather correctly with 360K diskettes but can destroy information on high- capacity diskettes. There still are viruses which determine whether the file is COM or EXE not according to the internal structure of the file but according to its extension. And of course if the format of the file does not match the file extension, this file becomes unusable after it has been infected. System lock-ups are also possible when a resident virus infects a newer version of DOS, or while running under Windows, or also with other powerful software systems. And so on.
Последнее изменение этой страницы: 2016-03-16; Просмотров: 899; Нарушение авторского права страницы