cypto and PKI Flashcards
(26 cards)
what is cryptography?
science of encrypting or hiding information
what is differential cryptanalysis
compare inplut plaintext to output ciphertext to determine encryption key
what is linear cryptanalysis
takes plaintext through a simplified cipher to deduce what the encryption key is likely to be
why is hashing done
to provide intergrity
why are digital signatures used
provide non-repudiation
different types of data usage?
data in transit, data at rest, and data in use
what is in a symmetric algorithm
a private shared key used to encrypt and decrypt data
what are the common symmetric algorithms?
3DES, AES, Blowfish, twofish, and RC4
what is asymmetric algorithms?
uses two keys instead of one example is PKI
what two keys are used in PKI?
private and public key
what are some popular asymmetric algorithms?
RSA, diffie-hellman, ECC, and ElGamal
diffusion
form of dispersion in plaintext and ciphertext
confusion
randomness of output increases entropy
collison
two inputs same hash output
ephermal key?
used only once after generation keys
what data does tls and ssl protect?
data in transit
what is data at rest encryption example?
whole disk encryption
cryptographic provider?
library that implements cryptographic functions
does diffie hellman allow in band or out of band key exchange?
in band even if entire data stream is being viewed
why is salting used?
provide more entropy eliminate problem of identical passwords
what modes are the most secure?
CBC and CTM/CTR
what are two encryption operation modes?
block and stream
why isn’t asymmetric suitable for bulk encryption?
because they are slower than symmetric methods
difference between dhe and ecdhe in diffie hellman?
ecdhe uses ecc while dhe uses temporary key
