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Рецензенты старший преподаватель кафедры английской филологии факультета ргф ивГУ, к ф. н
Topics for Essays, Oral or Written Reports
A day in a hacker’s life.
Hackers of today.
If I were a hacker
Hacking for fun or running for life?
Do we need hackers?
Essay Selection for Reading as a Stimulus for Writing
HACKERS OF TODAY
Hackers, having started as toy railroad circuitry designers in the late fifties, are completely new people now. Once turned to computers, they became gods and devils. Nowadays holders and users of the IVorld Wide Web hide their PCs under passwords when the keyword “hacker” is heard. When and how did this change take place? Why are we so frightened of Hacker The Mighty and The Elusive?
One of the legends says that hackers have changed under the influence of "crackers ” — the people who loved to talk on the phone at somebody
else's expense. Those people hooked up to any number and enjoyed the pleasure of telephone conversation, leaving the most fun — bills — for the victim. Another legend tells us that modern hackers were bom when a new computer game concept was invented. Rules were very simple: two comput er programs were fighting for the reign on the computer. Memory, disk- space and CPU time were the battlefield. The results of that game are two in number and are well known: hackers and computer viruses. One more story tells that the “new ” hackers came to existence when two MIT stu dents that attended the AI Lab found an error in a network program. They let people, responsible for the network, know but with no result. The of fended wrote a code that completely paralyzed the network and only after that the error was fixed. By the way, those students founded The Motorola Company later.
Today, when the Internet has entered everyone’s house there’s no shield between a hacker and your PC. You can password yourself up, but then either hackers will crack your PC anyway or nobody will enter your site, because passwords kill accessibility. If your PC is easy to access no one can guarantee what’ll happen to your computer - hackers, you know them.
Monsters? Chimeras? Not at all! Every hacker is a human being and has soft spots: good food, pretty girls or boys (it happens both ways), classical music, hot chocolate at the fireplace, apple pie on Sunday. Hack er is first of all a connoisseur, a professional with no computer secret out of his experience. And what is the application for skills depends on him, God, and Holy Spirit.
Unit VI. Computer Security Prereading Discussion
What are some common motivations for computer crime?
What is computer security?
What threatens a computer system?
Was the first bug real?
What viruses do you know?
What does biometrics study?
What is cryptography?
Reading AnalysisVOCABULARY LISTNouns: ransom, theft, espionage, imposter, forgery, advocate, fin gerprints, distortion, purchase, vendor.Verbs: safeguard, entitle, claim, arise, encrypt, evade, circumvent, override.Adjectives: vulnerable, legitimate, thorough, distinct, promising, plain, secure, particular.Word combinations: white-collar crime, to keep secret, under way, by chance, needless to say, security provisions, credit card holder, at the intersection of. TEXT I. SECURITY: PLAYING IT SAFE
The computer industry has been extremely vulnerable in the mat ter of security. Computer security once meant the physical securi ty of the computer itself — guarded and locked doors. Computer screens were given dark filters so others could not easily see the data on the screen. But filters and locks by no means prevented access. More sophisticated security means safeguarding the computer sys tem against such threats as burglary, vandalism, fire, natural di sasters, theft of data for ransom, industrial espionage, and various forms of white-collar crime.
Emphasis on Access and Throughput. For the last decade or so, computer programmers have concentrated on making it easy for people to use computer systems. Unfortunately, in some situations the systems are all too easy to use; they don’t impose nearly enough restrictions to safeguard confidential information or to prevent un authorized persons from changing the information in a file.
It’s as if a bank concentrated all its efforts on handing out money as fast is it could and did very little to see that the persons who requested the money were entitled to it. Of course, a real bank works just the opposite way, checking very carefully before handing out any money. Computer systems that handle sensitive personal and financial data should be designed with the same philosophy in mind.
Positive Identification of Users. A computer system needs a sure way of identifying the people who are authorized to use it. The identifi cation procedure has to be quick, simple, and convenient. It should be so thorough that there is little chance of the computer being fooled by a clever imposter. At the same time, the computer must not reject legitimate users. Unfortunately, no identification system currently in use meets all these requirements.
At present, signatures are widely used to identify credit-card hold ers, but it takes an expert to detect a good forgery. Sometimes even a human expert is fooled, and there is no reason to believe that a computer could do any better.
A variation is to have the computer analyze a person’s hand move
ments as he signs his name instead of analyzing the signature itself. Advocates of this method claim that different persons’ hand move ments are sufficiently distinct to identify them. And while a forger might learn to duplicate another person’s signature, he probably would not move his hand exactly the way the person whose signa ture he was forging did.
Photographs are also sometimes used for identification. But, peo ple find it inconvenient to stop by a bank or credit card company and be photographed. Companies might lose business if they made the pictures an absolute requirement. Also, photographs are less useful these days, when people frequently change their appear ance by changing the way they wear their hair. Finally, computer programs for analyzing photographs are still highly experimental.
Cash-dispensing systems often use two identification numbers: one is recorded on amagnetic stripe on the identification card, and the other is given to the cardholder. When the user inserts his card into the cash-dispensing terminal, he keys in the identification number he has been given. The computer checks to see that the number recorded on the card and the one keyed in by the user both refer to the same person. Someone who stole the card would not know what number had to be keyed in to use it. This method currently is the one most widely used for identifying computer users.
For a long time, fingerprints have provided a method of positive identification. But they suffer from two problems, one technical and one psychological.
The technical problem is that there is no simple system for com paring fingerprints electronically. Also, most methods of taking fin gerprints are messy. The psychological problem is that fingerprints
are strongly associated in the public mind with police procedures. Because most people associate being fingerprinted with being ar rested, they almost surely would resist being fingerprinted for rou tine identification.
Voiceprints may be more promising. With these, the user has only to speak a few words into a microphone for the computer to analyze his voice. There are no psychological problems here. And technically it’s easier to take and analyze voiceprints than finger prints. Also, for remote computer users, the identifying words could be transmitted over the telephone.
However, voiceprints still require more research. It has yet to be proved that the computer cannot be fooled by mimics. Also, tech nical difficulties arise when the voice is subjected to the noise and distortion of a telephone line.
Even lip prints have been suggested.But it’s doubtful that kissing computers will ever catch on.
To date, the most reliable method of positive identification is the card with the magnetic stripe. If the technical problems can be worked out, however, voiceprints may prove to be even better.
Data Encryption. When sensitive data is transmitted to and from remote terminals, it must be encrypted (translated into a secret code) at one end and decrypted (translated back into plain text) at the other. Files also can be protected by encrypting the data before storing it and decrypting it after it has been retrieved.
Since it is impractical to keep secret the algorithms that are used to encrypt and decrypt data, these algorithms are designed so that their operation depends on a certain data item called the key. It is the key that is kept secret. Even if you know all the details of the encrypting and decrypting algorithms, you cannot decrypt any mes sages unless you know the key that was used when they were en crypted.
For instance, the National Bureau of Standards has adopted an algorithm for encrypting and decrypting the data processed by fede ral agencies. The details of the algorithm have been published in the Federal Register. Plans are under way to incorporate the algorithm in special purpose microprocessors, which anyone can purchase and install in his computer.
So the algorithm is available to anyone who bothers to look it up or buy one of the special purpose microprocessors. But the opera tion of the algorithm is governed by a sixty-four-bit key. Since there are about [022 possible sixty-four-bit keys, no one is likely to discover the correct one by chance. And, without the correct key, knowing the algorithm is useless.
A recent important development involves what are called public- key cryptosystems.
In a public-key cryptosystem, each person using the system has two keys, a public key and a private key. Each person’s public key is published in a directory for all to see; each person’s private key is kept secret. Messages encrypted with a person’s public key can be decrypted with that person’s (but no one else’s) private key. Mes sages encrypted with a person’s private key can be decrypted with that person’s (but no one else’s) public key.
Protection through Software. The software of a computer system, particularly the operating system, can be designed to prevent un authorized access to the files stored on the system.
The protection scheme uses a special table called a security matrix.
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Data A
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Data В
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Data С
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User A
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Read
Modify
Execute
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Modify
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Read
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User В
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Read
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Modify
Execute
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Modify
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User С
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Read
Modify
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Read
Execute
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Read
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Each row of the security matrix corresponds to a data item stored in the system. Each entry in the table lies at the intersection of a particular row and a particular column. The entry tells what kind of access the person corresponding to the row in which the entry lies has to the data item corresponding to the column in which the entry lies.
Usually, there are several kinds of access that can be specified. For instance, a person may be able to read a data item but not change it. Or he may be able to both read and modify it. If the data is a program, a person may be able to have the computer execute the
program without being able either to read or modify it. Thus, people can be allowed to use programs without being able to change them or find out how they work.
Needless to say, access to the security matrix itself must be re stricted to one authorized person.
Also, the software has to be reliable. Even the software issued by reputable vendors may be full of bugs. One or more bugs may make it possible for a person to circumvent the security system. The secu rity provisions of more than one computer system have been evad ed by high school and college students.
Restricting the Console Operator. Most computer systems are ex tremely vulnerable to the console operator. That’s because the op erator can use the switches on the computer’s control panel to insert programs of his own devising, to read in unauthorized pro grams, or to examine and modify confidential information, in cluding the security matrix. In the face of these capabilities, any software security system is helpless. Computer systems for han dling sensitive information must be designed so that the console operator, like other users, works through the software security system and cannot override it. One solution is to incorporate the security system in firmware instead of software, so that unautho rized changes to it cannot be made easily.
EXERCISES
Give synonyms to:
To encrypt, to secure, confidential, biometric, recognition, imposter, to meet requirements, to detect, to lose business, appearance, to incorpo rate, unless, to circumvent.
Give antonyms to:
Convenient, advocate, to reject, to encrypt, legitimate, messy, autho rized, white-collar crime, to safeguard info, sensitive, to retrieve data, practical, by chance, private.
Answer the questions:
What is computer security?
What is the most serious problem: the loss of hardware, software, or the loss of data?
How does a computer system detect whether you are the person who should be granted access to it?
What are the shortcomings of each biometric means?
What is to prevent any user from copying PC software onto dis kettes?
What steps can be taken to prevent theft or alteration of data?
What is the weakest link in any computer system?
Should a programmer also be a computer operator?
What is a security matrix?
Can the computer industry risk being without safeguards for securi ty and privacy?
Put the proper words into sentences:
foolproof, complicated, virus, unauthorized, crime, fingerprint, alter ing, messages.
Computer security is more ... today than it was in the past.
International literature tells lurid stories about computer viruses ... — about bank swindles, espionage, ... sent from one computer to destroy the contents of others.
Movies like War Games have dramatized the dangers from ... entry to the computer systems that control nuclear weapons.
Methods used in computer-based criminal activity range from switch ing or ... data as they enter the computer, to pulling self-conceal ing instruction into the software.
The person who develops a ... lock for the computer data will make a fortune.
.. is the name generally given to software that causes ... of computer files.
People must be taught that some kinds of help, such as assisting ... users with passwords are inappropriate.
According to a published article, the Mafia has kidnapped an IBM executive and cut off his finger because it needed his ... to breach a computer security system.
Data sent over communication lines can be protected by encryp tion, the process of scrambling ...
JO. Firewall is security measures taken to block ... access to an Internet site.
Construct other sentences of these patterns:
All these systems are too easy to use.
It’s as if a bank concentrated all its efforts on handing out money as fast as it could.
The identification procedure has to be quick and simple.
It takes an expert to detect a good forgery.
The voice is subjected to the noise and distortion of a telephone line.
It is the key Ihal is kept secret.
You cannot decrypt any message unless you know the key.
No one is likely to discover the correct algorithm by chance.
The security system is incorporated in firmware, so that unautho rized changes to it cannot be. made easily.
Suppose 1 want to send you a signed message
TEXT II. CHECKING YOUR OWN SECURITY A Personal Checklist for Hardware. With the subject of security fre$h in your mind, now is a good time to consider a checklist for your own personal computer and its software. We will confine this list to a computer presumed to be in the home.
No eating, drinking, or smoking near the computer.
Do not place the computer near open windows or doors.
Do not subject the computer to extreme temperatures.
Clean equipment regularly.
Place a cable lock on the computer.
Use a surge protector.
Store diskettes properly in a locked container.
S. Maintain backup copies of all files.
Store copies of critical files off site.
A Personal Checklist for Software. A word of prevention is in order. Although there are programs that can prevent virus activity, protecting yourself from viruses depends more on common sense than on building a“fortress” around the computer. Here are afew common-sense tips:
If your software allows it, follow write-protect measures for your floppy disks before installing any new software. If it does not allow it, write-protect the disks immediately after instal lation.
Do not install software unless you know it is safe. Viruses tend to show up on free software acquired from sales representa tives, resellers, computer repair people, power users, and consultants.
Make your applications (and other executable files) read only. This will not prevent infection, but it can help contain those viruses that attack applications.
Stop the so-called sneakemet crowd. This is the group that moves around the office (in sneakers, of course) and prefers to transfer files quickly via floppy disk.
Make backups. This is a given: Always back up your hard disk and floppies.
EXERCISES
Find in the text the English equivalents to:
давно пора; тема безопасности; перечень; подвергать; резервные копии; блокировка питания; защита от выброса; выполняемый файл; здравый смысл; защитить данные в отдельном файле или на целом диске; только для чтения; помешать заражению; с помощью; передавать файл.
Answer the following questions:
What are security devices?
What can help minimize theft?
What can a surge protector do?
Why is the so-called sneakemet crowd dangerous?
Translate into English:
Еще в школе Билл Гейтс сумел подобрать ключ к системе защиты и постоянно воровал время эксплуатации машины.
Нарушение авторского права — незаконное копирование, в частности, программы.
Пароль — это набор символов, используемых в качестве кода к вычислительной системе или базе данных. Компьютерные ху лиганы могут легко подобрать пароль, если он представляет собой инициалы или последовательные ряды чисел.
Знаете ли вы, как вести себя в Интернете? Существует ли этика Сетевого Братства?
Тащат все: личные коды кредитных карточек, авторские музы
кальные произведения, последние компьютерные игры. Ха керы называют это дележкой, остальное — откровенным во ровством.
Легальный компьютерный бизнес поднимается на свою защиту.
Если вы используете компьютер в своем бизнесе, то вы долж ны иметь антивирусные программы и обновлять их постоянно.
Есть два способа избежать заражения компьютерными вируса ми: не устанавливать новое программное обеспечение без про верки и не загружать бесплатную информацию из сети.
Самыми быстрыми способами нелегального распространения программного обеспечения сейчас являются: воровство, взлом и торговля краденым.
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