X. Translate in written form the passage «An analogy for public-key encryption is similar to …. .... To check that the message has not been tampered with» into Ukrainian using your active vocabulary

XI. Write an abstract (100-120 words) of the text «Data security» (see Appendix b) unit 6. Information security

Before you read

I. Test yourself

1) What do you know about information security?

2) Why is information security a vital task for users?

3) How can you protect your computer information?

II. Match the word to its explanation

1) address

2) modification

3) integrity

4) create

5) maintenance

6) available

7) restrict

8) encrypt

9) sophisticated

10) method

a) to cause to come into existence

b) the process of preserving a condition

c) able to be used or obtained

d) the conventional form by which the location of a building is described

e) put a limit on

f) adherence to moral principles; honesty

g) the action of modifying something

i) developed to a high degree of complexity

j) a way of proceeding or doing something

k) convert data into a cipher or code

III. Match the English and Ukrainian equivalents

1) authorized user a) захист з використанням пароля

2) hash table search в) захист пам’яті

3) user authorization file с) діалоговий; оперативний; під’єднаний

4) sort utility d) тотожність

5) certainty value e) блокувати, відключати

6) vertical parity f) привілейований користувач

7) encryption key g) файл інформації про користувачів

8) password protection h) геш-пошук

9) boundary protection i) програма сортування

10) on-line j) поздовжній контроль парності

11) identify k) ключ шифрування

12) disable l) ймовірність

IV. Read and translate the following text

Information security

Information security is the process of protecting data from unauthorized access, use, modification or disruption. The terms information security, computer security and information assurance are frequently used interchangeably. These fields are interrelated, however, there are some subtle differences between them. These differences lie primarily in the approach to the subject, the used methodologies and the areas of concentration. Information security is concerned with the confidentiality, integrity and availability of data.

It is virtually impossible to get a driver’s licence, rent an apartment, obtain medical care, or take out a loan without disclosing a great deal of very personal information about ourselves, such as our name, address, telephone number, date of birth, social security number, marital status, number of children, mother's maiden name, income, place of employment, medical history, etc. This is all very personal and private information, yet we are often required to provide such information in order to transact business.

In information security, integrity means that data cannot be created, changed, or deleted without authorization. It also means that data stored in one part of a database system is in agreement with other related data stored in another part of the database system (or another system). A loss of integrity can occur in such cases as:

- when a database system is not properly shutdown before maintenance is performed or the database server suddenly loses electrical power;

- an employee accidentally, or with malicious intent deletes important data files;

- if a computer virus is released onto the computer;

- when an on-line shopper is able to change the price of the product they are purchasing.

The concept of availability means that the information, the computing systems used to process the information, and the security controls used to protect the information are all available and functioning correctly when the information is needed. The opposite of availability is denial of service (DOS).

Access to protected information must be restricted to people who are authorized to access the information. The computer programs, and in many cases the computers that process the information, must be also authorized. This requires mechanisms to control the access to protected information. The sophistication of the access control mechanisms should be in parity with the value of the information being protected – the more sensitive or valuable the information the stronger the control mechanisms need to be. Identification is an assertion of who someone is or what something is. If a person makes the statement "Hello, my name is John Doe." he makes a claim of who he is. However, his claim may or may not be true. Before John Doe can be granted access to protected information it will be necessary to verify that the person claiming to be John Doe really is John Doe.

Authentication is the act of verifying a claim of identity. When John Doe goes into a bank to make a withdrawal, he tells the bank teller he is John Doe (a claim of identity). The bank teller asks to see a photo ID, so he hands the teller his driver’s licence. The bank teller checks the licence to make sure it has John Doe printed on it and compares the photograph on the licence against the person claiming to be John Doe. If the photo and name match the person, then the teller has authenticated that John Doe is who he claimed to be.

On computer systems in use today, the Username is the most common form of identification and the Password is the most common form of authentication. Usernames and passwords are slowly being replaced with more sophisticated authentication mechanisms.

After a person, program or computer has successfully been identified and authenticated then it must be determined what information they are permitted to access and what actions they will be allowed to perform (run, view, create, delete, or change). This is called authorization.

Information security uses cryptography to transform usable information into a form that renders it unusable by anyone other than an authorized user; this process is called encryption. Information that has been encrypted (rendered unusable) can be transformed back into its original usable form by an authorized user, who possesses the cryptographic key, through the process of decryption. Cryptography is used in information security to protect information from unauthorized or accidental discloser while the information is in transit and while information is in storage.

Cryptography provides information security with other useful applications as well including improved authentication methods, message digests, digital signatures and encrypted network communications. Secure applications such as Telnet and FTP are slowly being replaced with more secure applications such as SSH that use encrypted network communications. Wireless communications can be encrypted using special protocols. Software applications such as GNUPG or PGP can be used to encrypt data files and E-mail.

Cryptography can introduce security problems when it is not implemented correctly. The length and strength of the encryption key is also an important consideration. A key that is weak or too short will produce weak encryption. The keys used for encryption and decryption must be protected with the same degree of rigor as any other confidential information. They must be protected from unauthorized disclosure and destruction and they must be available when needed.