Ex. 3 Look at these phrases from the text and explain the underlined parts in your own words
Date: 2015-10-07; view: 474.
Ex. 2 Find answers to the following questions
Ex. 1 Match the English - Ukrainian equivalents
1. lock-up a) ïàðîëü; êëþ÷ äîñòóïó
2. proof listing â) ïåðåõ³ä ç áëîêóâàííÿì
3. mailbox service ñ) çàêðèòà áàçà äàíèõ
4. pass key d) ðîçðàõîâàíå çíà÷åííÿ
5. authenticity e) ïåðåäà÷à ïîâ³äîìëåíü
6. private database f) êîíòðîëüíèé ðîçäðóêîâàíèé ìàòåð³àë
7. mail group g) àñèìåòðè÷íå â³äíîøåííÿ
8. algorithm scheme h) òóïèê, òóïèêîâà ñèòóàö³ÿ
9. message passing i) ñëóæáà ïî÷òîâèõ ñêðèíüîê
10. locking escape j) äîñòîâ³ðí³ñòü
11. calculated value k) ãðóïà åëåêòðîííî¿ ïîøòè
12. asymmetric relation l) ñõåìà àëãîðèòìó
1. What is asymmetric cryptography called?
2. What's the principal difference between public and private key?
3. What's the main difference between symmetric and asymmetric cryptography?
4. What are the main branches of public key?
5. How can the central problem for public key cryptography be solved?
6. How can you break an algorithm?
7. Why do we use digital signature?
8. How is authentication performed? How can you achieve authentication?
9. Do all asymmetric key algorithms operate the same way?
1. The private key is kept secret, while the public key may be widely distributed.
2. ... a message encrypted with a recipient's public key cannot be decrypted…
3. This is used to ensure confidentiality.
4. The judicious use of these techniques enables a wide variety of applications.
5. If another user can successfully decrypt it using the corresponding public key…
6. None of these algorithms can be proved secure in as absolute sense as the one-time pad has.
7. She then sends the box to Bob through regular mail.
8. … which he has somehow obtained previously, maybe by a face-to-face meeting…
9. The critical advantage in an asymmetric key system is …
10. This prevents a third party from copying a key while…
Ex. 4 Complete each gap in this text with a suitable word from the list
Public-key cryptography may be 1) _____ to impersonation, however, even if users' 2) _____ keys are not available. A successful attack on a 3) _____ authority will allow an adversary to impersonate whomever the 4) _____ chooses to by using public-key certificate from the compromised authority to bind a key of the adversary's choice to the name of another 5) _____.
Is some situations, public-key cryptography is not 6) _____ and secret-key cryptography alone is sufficient. This includes environments where secure 7) _____ agreement can take place. It also includes environments where a single 8) _____ knows and manages all the keys. Since the authority knows everyone's keys already, there is not much 9) _____ for some to be “public” and others “private”. Also, public-key 10) _____ is usually not necessary in a single-user environment. For example, if you want to keep your personal files 11) _____ ,you can do so with any secret-key encryption 12) _____ using, say, your personal 13) _____ as the secret key. In general, public-key cryptography is best suited for an open 14) _____ environment.
Public-key cryptography is not meant to 15) _____ secret-key cryptography, but rather to supplement it, to make it more 16) _____. The first use of public-key 17) _____ was for secure key exchange in an otherwise secret-key system; this is still one of its 18) _____ functions. Secret-key cryptography remains extremely 19) _____ and is the subject of ongoing study and research. Some secret-key 20) _____ are discussed in the sections on Block Ciphers and Stream Ciphers.
user important authority encrypted
replace advantage multi-user certification
cryptosystems vulnerable secure primary
adversary techniques cryptography necessary
secret-key password private algorithm
Ex. 5 Translate in written form the passage “A central problem for public-key cryptography is … by the recipient's paired private key” into Ukrainian using your active vocabulary.
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