COMPUTER ETHICS AND SECURITY
CRYPTOGRAPHY AND ENCRYPTION
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Frequency analysis
|
|
|
Cryptography
|
|
|
Encription
|
|
|
Decription
|
Detailed explanation-1: -In cryptanalysis, frequency analysis (also known as counting letters) is the study of the frequency of letters or groups of letters in a ciphertext. The method is used as an aid to breaking classical ciphers.
Detailed explanation-2: -Frequency analysis consists of counting the occurrence of each letter in a text. Frequency analysis is based on the fact that, in any given piece of text, certain letters and combinations of letters occur with varying frequencies.
Detailed explanation-3: -frequency analysis on a transposition cipher shows that the constituent letters are what would be expected in a standard text (example: “e” is the most common English letter).
Detailed explanation-4: -Classic frequency analysis involves tallying up each letter in the collected ciphertext and comparing the percentages against the English language averages. If the letter “M” is most common then it is reasonable to guess that “E"–>"M” in the cipher because E is the most common letter in the English language.