Task А. Choose the correct form of Passive Voice.

1. The assumed threats to security specify/ specified/are specified below.

2. The unauthorized disclosure has been prevented/has prevented/has being prevented.

4. The repeatable key based/is based/bases on the following principles.

5. Knowing about the risk, one is prepares/prepared/is prepared better.

6. A sound IRM program founds/founded/is founded on a well thought out IRM policy infrastructure.

7. An event, the occurrence of which could have an undesirable impact, is defined/define/ defines as threat.

8. A sound IRM program founds/founded/is founded on a well thought out IRM policy infrastructure.

9. The underlined secure network services installed/was installed/were installed in accordance with the operational documentation.

Task B. Put the verbs in brackets in the correct form of Passive Voice.

1. Uncertainty (measure) inversely with the respect to confidence.

2. The papers of the conference (translate) into 12 languages.

3. Both expected frequency and exposure factor for fire (increase) by not having a fire suppression system.

4. Exposure factor (express) as a percent.

5. Generally accepted Information Security Principles (base) on an Authoritative Foundation of supporting documents and guidelines.

6. It is essential that the process of analyzing and assessing risk (understand) by all sides.

7. Uncertainty (measure) inversely with the respect to confidence.

8. This work (finish) next month.

9. The papers of the conference (translate) into 12 languages.

10. Both expected frequency and exposure factor for fire (increase) by not having a fire suppression system.

11. The system (develop) in 1998.

12. Exposure factor (express) as a per cent.

13. Generally accepted Information Security Principles (base) on an Authoritative Foundation of supporting documents and guidelines.

14. It is essential that the process of analyzing and accessing risk (understand) by all sides.

Task C. Put the verbs in brackets in the correct form, Active or Passive Voice.

1. The curves (show) in figure 4.

2. Our analysis (suggest) the spheres of practical application of our technique.

3. Our ongoing work (focus) on the use of other biometric measurements.

4. If the BUSINESS module (choose) this can (use) to generate a detailed questionnaire appropriate to the system under review.

5. Nowadays real-time operating system (employ) in consumer devices.

6. These systems (share) an unmatched reputation for operating 24 hours a day, 365 a year, nonstop.

7. Back in the 90-s, Anti-virus researchers first (fight back) by creating special detection routines designed to catch each polymorphic virus, one by one.

8. By hand, line by line, they (write) special programs.

9. W.F.Friedman’s monograph «The Index of Coincidence and its Application in Cryptography» (appear) in 1918.

10. US Army and Navy (work) entirely in secret, when their specialists (begin) making fundamental advances in cryptography.

12. H.Feistel, who earlier (work) on identification friend or foe devices for the Air Force, (change) the sphere of his scientific interests.

Communication.

Writing.

 

Unit 4. MODERN METHODS OF CRYPTANALYSIS.

Memorize the terms

1. Read the following terms and their definitions and memorize them:

incomprehensible ciphertext – encrypted message that is impossible to read and understand

remove one bit of drudgery – simplify monotonous work

overlapping superencipherment groups – partial matching of encrypted messages

avalanche property of DES - changing a single bit in a DES key results in every bit of the enciphered block being changed randomly after only a few rounds

ciphertext-only solution – process of decryption when cryptanalyst has only encrypted text to recover the plaintext

mimic the process – imitate, simulate the process

flaw – disadvantage, demerit, weak point in the system

2. Match the following words with their Russian equivalents:

chain of discrete elements	отсеченный дифференциал
hill climbing algorithm	пробный ключ
truncated differential	алгоритм нахождения экстремума
encipher the known plaintext	последовательность дискретных компонентов
trial key	зашифровать имеющийся (известный) открытый текст

3. Match the following words with their synonyms:

unrelated (characteristics)	scaling, computation, evaluation
xor	punched card machines
obtain clue	unconnected
converted unit record equipment	derive, extract, obtain key
calculus	исключающее «или»

Reading

Pre-reading task.

What do you know about cryptanalysis? What cryptographic algorithms can you name?