P2L5 Intro to Cryptography Flashcards
avalanche effect
Small change causes large consequences. Contextualized in hashing algorithms. Knowing one password for one hash means little when trying to determine hash of very similar password.
block cipher
Take input of text blocks of plain text of fixed size blocks and produces blocks of cipher text of equal size
DES vs AES
different block sizes and key lengths
a method where a specific known plaintext is compared to its ciphertext
known plain text attack
a method where attacker compares ciphertexts with its known plain text (he is choosing plaintext randomly)
chosen plain text attack
attack in which attacker analyzes effect of changes in input on encrypted output
differential analysis
method to determine the encryption function by analyzing known phrases and their encryption
linear cryptanalysis
in RSA, the public key encryption or decryption?
both
asymmetric encryption strengths vs symmetric
scalability and distribution of session keys
solution to knowing that public key received is from real entity and not forgery
public key certificate
public key certificate
signed with CA’s private key, includes period of validity, public key of the issuing party
how to validate public key cert
- certificate data is hashed
- hash is signed with private key of CA and appended to cert
- receiving party verifies cert by hashing the cleartext portion of the cert. Then recipient uses the CA’s public key to decrypt/verify signature of CA. If values match, then all is well.
digital envelopes encapsulate what?
It contains a symmetric key encrypted with the recipient’s public key. It an encrypted message which can only be decrypted with the symmetric key.
inputs into encryption algorithm:
key and plaintext
