CSNT 181 2025/2026 EXAM GRADED A+
(QUESTIONS AND ANSWERS) 100%
ACCURATE
Symmetric encryption - Uses a single key to encrypt and decrypt data.
Asymmetric encryption - uses two keys: a public key known to everyone and a private or secret key
known only to the recipient. A message encrypted with a public key can be decrypted only with the
same algorithm used by the public key and requires the recipient's private key, too. Anyone
intercepting the message cannot decrypt it because he or she does not have the private key.
Cryptographic hashing - Converts data into a hash, or unique signature. The hash can't be turned
back into the original data, but can be compared to the data to verify its integrity and/or
authenticity.
Caesar cipher - Simple substitution cipher
ROT13 - One type of substitution cipher in which the entire alphabet is rotated 13 steps.
Vigenère cipher - A polyalphabetic cipher, which uses a keyword to look up values in a table
composed of all possible Caesar ciphers.
one-time pad (OTP) - Combining plaintext with a random key to create ciphertext that cannot be
broken mathematically.
Transposition cipher - A cipher that rearranges the order of characters in a message.
RC4 - Stream cipher that is quick to encode or decode. (Obsolete today due to vulnerabilities)
AES - Advanced Encryption Standard. Symmetric block cipher. Variable block length up to 256-bits,
but the AES version specifies only 128-bit blocks (good enough for most purposes). It can use 128-,
192-, or 256-bit keys.
(QUESTIONS AND ANSWERS) 100%
ACCURATE
Symmetric encryption - Uses a single key to encrypt and decrypt data.
Asymmetric encryption - uses two keys: a public key known to everyone and a private or secret key
known only to the recipient. A message encrypted with a public key can be decrypted only with the
same algorithm used by the public key and requires the recipient's private key, too. Anyone
intercepting the message cannot decrypt it because he or she does not have the private key.
Cryptographic hashing - Converts data into a hash, or unique signature. The hash can't be turned
back into the original data, but can be compared to the data to verify its integrity and/or
authenticity.
Caesar cipher - Simple substitution cipher
ROT13 - One type of substitution cipher in which the entire alphabet is rotated 13 steps.
Vigenère cipher - A polyalphabetic cipher, which uses a keyword to look up values in a table
composed of all possible Caesar ciphers.
one-time pad (OTP) - Combining plaintext with a random key to create ciphertext that cannot be
broken mathematically.
Transposition cipher - A cipher that rearranges the order of characters in a message.
RC4 - Stream cipher that is quick to encode or decode. (Obsolete today due to vulnerabilities)
AES - Advanced Encryption Standard. Symmetric block cipher. Variable block length up to 256-bits,
but the AES version specifies only 128-bit blocks (good enough for most purposes). It can use 128-,
192-, or 256-bit keys.
