C178 Cryptography 2c

its4forscience's version from 2018-01-14 18:02


Question Answer
characteristic number 1 of hash functionsIt must be one-way, not reversible
characteristic number 2 of hash functionsVariable-length input produces fixed-length output, hash always same size
characteristic number 3 of hash functionsThe algorithm must have few or no collisions, two different inputs does not give the same output
one-way hash designed to ensure the integrity of a message, used with an encryption protocolSecure Hash Algorithm (SHA)
produces a 160-bit hash valueSecure Hash Algorithm (SHA)
has several sizes: 224, 256, 334, and 512 bit, the most widely used hashSHA-2
newest version of this algorithm, produces a 128-bit hash, no longer recommendedMD5 (SHA-1or SHA-2 are the recommended alternatives)
algorithm based on MD4, replaced by RIPEMD-160RACE Integrity Primitives Evaluation Message Digest (RIPEMD)
symmetric cipher developed in the old Soviet Union, fixed lenght of 256 bitsGOST
used prior to Windows NT for authentication, replaced by NTLMLANMAN
released with Windows NT, uses MD4/MD5 hashing, for authenticationNTLM (NT LAN Manager)
all of the possible hashes are computed in advance, used to break a hashrainbow table
countermeasure to rainbow tables, addition of bits before or after the hashsalt
processes used to take a key that might be a bit weak and make it strongerKey stretching
makes a key longer, thus less susceptible to brute-force attacksKey stretching
part of PKCS #5 v. 2.01, applies some function to the password w/ Salt to produce a derived keyPBKDF2 (Password-Based Key Derivation Function 2)
uses a derivation of the Blowfish algorithm, hash a password and add Salt to itBcrypt (used with passwords)
looks at blocks of encrypted msg to determine if any common patterns existFrequency analysis (type of attack)
attacker obtains ciphertexts corresponding to a plaintexts of their choosingChosen Plaintext (type of attack)
attacker obtains ciphertexts encrypted under two different keysRelated Key Attack (type of attack)
when humans do something stupid, like sending in cleartextExploiting Human Error (type of attack)
popular for Wi-Fi encryptionRC4
couples the RC4 encryption algorithm with TKIPWPA (Wi-Fi Protected Access)
favors Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP)WPA2 (Wi-Fi Protected Access 2)
uses Counter Mode with Cipher Block ChainingWPA2 (Wi-Fi Protected Access 2)