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6. Answer the questions

What are the main terms of cryptography?

What can be a plaintext?

What should a specialist take into account when he wants to create his own or use some developed products?

What are the basic characteristics of the cryptographic protocols mentioned in the text?

7. Write if the following statements are true or false.

  1. Try to create your own protocol as it’ll be more secure.

  2. A method of encryption is only secure if even with this complete access, the eavesdropper is still unable to recover the original plaintext from the ciphertext.

  3. Plaintext is binary so it can be any form.

  4. If you use IPSec, you may not use the authentication because the protocol is secure enough to ignore it.

  5. Kerberos works by giving authenticated users "tickets", granting them access to various services on the network.

Vocabulary tasks

8. Form different parts of speech and translate them

Cryptography

9. Give your definitions of the following terms.

Plaintext, encryption, ciphertext, decryption

10. Make the word combinations

  1. incompatible

a) of tools

  1. communicating

b) protection

  1. keyring

c) attack

  1. brute

d) authentication

  1. integrity

e) standards

  1. string

f) information

  1. optional

g) force

  1. authenticate

h) server

  1. man-in-the middle

i) of binary

  1. suite

j) host

11. What do the following abbreviations from Text 1 mean?

RSA, IPSec, VPN, SSL

12. Find abbreviations in Text 2 and comment on their meaning.

13. Complete the text using the words given below.

brute force, encrypt, to break, a key length, hardware

For symmetric-key encryption (e.g., for bulk encryption), don't use ….. less than 90 bits if you want the information to stay secret through 2016 (add another bit for every additional 18 months of security). For encrypting worthless data, the old DES algorithm has some value, but with modern …. it's too easy to break DES's 56-bit key using …. . If you're using DES, don't just use the ASCII text key as the key - parity is in the least (not most) significant bit, so most DES algorithms will …. using a key value well-known to adversaries; instead, create a hash of the key and set the parity bits correctly (and pay attention to error reports from your encryption routine). So-called ``exportable'' encryption algorithms only have effective key lengths of 40 bits, and are essentially worthless; in 1996 an attacker could spend $10,000 …. such keys in twelve minutes or use idle computer time to break them in a few days, with the time-to-break halving every 18 months in either case.