SANS 301 UPDATED Exam Questions
and CORRECT Answers
Cryptography - CORRECT ANSWER - the art of private communication in a public
environment
Key - CORRECT ANSWER - a numeric value of a given length (in bits)
Keyspace - CORRECT ANSWER - the range of values that can be used to construct a key
Ciphertext - CORRECT ANSWER - plaintext transformed into a nonhuman readable form
Encryption - CORRECT ANSWER - the process of turning plaintext into ciphertext
Decryption - CORRECT ANSWER - the process of turning ciphertext back into plaintext
Algorithm - CORRECT ANSWER - the public knowledge set of rules behind
cryptography (modern crypto uses math)
Cryptanalysis - CORRECT ANSWER - the art and science of breaking cryptography, also
called cryptanalytic attack
Nonrepudiation - CORRECT ANSWER - provides proof of the integrity and origin of
data; sender is the true sender, document has not been modified
Steganography - CORRECT ANSWER - hiding a message inside a picture, movie, or
similar type file, also used for digital watermarking
,Transposition - CORRECT ANSWER - reordering the letters of a message. Also called
permutation/obfuscation
Rail fence cipher - CORRECT ANSWER - every other letter 'falls thru the rails' then you
match up both stacks of letters (transposition)
Scytale cipher - CORRECT ANSWER - stick with specific diameter and taper, wrap hide
around stick to decode. Spartans 400 BC (transposition)
Column shift cipher - CORRECT ANSWER - rearrange the letters within block of text
boxes given a formula to read it (transposition)
Substitution - CORRECT ANSWER - replace letters of a message with other letters or
numbers using a formula
Monoalphabetic - CORRECT ANSWER - simple substitution cipher, replace plaintext
alphabet with one ciphertext alphabet, prone to frequency analysis & plaintext attack
Polyalphabetic - CORRECT ANSWER - replace plaintext alphabet with many ciphertext
alphabets, resistant to frequency analysis
Atbash cipher - CORRECT ANSWER - monoalphabetic, simply reversed the alphabet so
abc = zyx
Caeser cipher - CORRECT ANSWER - monoalphabetic, shifts alphabet by 3 characters
(ROT 3)
Vigenere cipher - CORRECT ANSWER - 'undecipherable cipher' a method of encrypting
alphabetic text by using a series of interwoven Caesar ciphers based on the letters of a keyword
, One-time pad - CORRECT ANSWER - unbreakable cipher if implemented right, one time
use & never again, substitution cipher, Gilbert Vernam 1917
XOR - CORRECT ANSWER - comparison of two binary bits & arrive at a third bit
Confidentiality & integrity - CORRECT ANSWER - Two services of encryption?
Confidentiality - CORRECT ANSWER - What does encryption provide?
Running key - CORRECT ANSWER - when the cryptographic key & the message are the
same length
words/phrases - CORRECT ANSWER - A cipher replaces letters, what does a code
replace?
Pseudo random number generator - CORRECT ANSWER - computers cannot generate a
truly random value, PRNG is random enough, but prone to weak key attack
Birthday attack - CORRECT ANSWER - certain keys are more likely to occur than others
Avalanche effect - CORRECT ANSWER - small change in plaintext = huge change in
ciphertext
Strong algorithm - CORRECT ANSWER - the rules that make encryption work, weak
math results in a mathematical attack
Mathematical attack - CORRECT ANSWER - occurs when encryption system is broken or
flawed
and CORRECT Answers
Cryptography - CORRECT ANSWER - the art of private communication in a public
environment
Key - CORRECT ANSWER - a numeric value of a given length (in bits)
Keyspace - CORRECT ANSWER - the range of values that can be used to construct a key
Ciphertext - CORRECT ANSWER - plaintext transformed into a nonhuman readable form
Encryption - CORRECT ANSWER - the process of turning plaintext into ciphertext
Decryption - CORRECT ANSWER - the process of turning ciphertext back into plaintext
Algorithm - CORRECT ANSWER - the public knowledge set of rules behind
cryptography (modern crypto uses math)
Cryptanalysis - CORRECT ANSWER - the art and science of breaking cryptography, also
called cryptanalytic attack
Nonrepudiation - CORRECT ANSWER - provides proof of the integrity and origin of
data; sender is the true sender, document has not been modified
Steganography - CORRECT ANSWER - hiding a message inside a picture, movie, or
similar type file, also used for digital watermarking
,Transposition - CORRECT ANSWER - reordering the letters of a message. Also called
permutation/obfuscation
Rail fence cipher - CORRECT ANSWER - every other letter 'falls thru the rails' then you
match up both stacks of letters (transposition)
Scytale cipher - CORRECT ANSWER - stick with specific diameter and taper, wrap hide
around stick to decode. Spartans 400 BC (transposition)
Column shift cipher - CORRECT ANSWER - rearrange the letters within block of text
boxes given a formula to read it (transposition)
Substitution - CORRECT ANSWER - replace letters of a message with other letters or
numbers using a formula
Monoalphabetic - CORRECT ANSWER - simple substitution cipher, replace plaintext
alphabet with one ciphertext alphabet, prone to frequency analysis & plaintext attack
Polyalphabetic - CORRECT ANSWER - replace plaintext alphabet with many ciphertext
alphabets, resistant to frequency analysis
Atbash cipher - CORRECT ANSWER - monoalphabetic, simply reversed the alphabet so
abc = zyx
Caeser cipher - CORRECT ANSWER - monoalphabetic, shifts alphabet by 3 characters
(ROT 3)
Vigenere cipher - CORRECT ANSWER - 'undecipherable cipher' a method of encrypting
alphabetic text by using a series of interwoven Caesar ciphers based on the letters of a keyword
, One-time pad - CORRECT ANSWER - unbreakable cipher if implemented right, one time
use & never again, substitution cipher, Gilbert Vernam 1917
XOR - CORRECT ANSWER - comparison of two binary bits & arrive at a third bit
Confidentiality & integrity - CORRECT ANSWER - Two services of encryption?
Confidentiality - CORRECT ANSWER - What does encryption provide?
Running key - CORRECT ANSWER - when the cryptographic key & the message are the
same length
words/phrases - CORRECT ANSWER - A cipher replaces letters, what does a code
replace?
Pseudo random number generator - CORRECT ANSWER - computers cannot generate a
truly random value, PRNG is random enough, but prone to weak key attack
Birthday attack - CORRECT ANSWER - certain keys are more likely to occur than others
Avalanche effect - CORRECT ANSWER - small change in plaintext = huge change in
ciphertext
Strong algorithm - CORRECT ANSWER - the rules that make encryption work, weak
math results in a mathematical attack
Mathematical attack - CORRECT ANSWER - occurs when encryption system is broken or
flawed
