Cryptology. By Greg Buss Pat Shields Barry Burke. What is Cryptology?. Cryptology is the study of “secret writing.” Modern cryptology combines the studies of computer science and mathematics for the purpose of encoding information to ensure that data is secure. Key terms.
Cryptography – from the Greek words kryptos, meaning “hidden”, and graphein, meaning “to write”. Literally secret writing.
Cryptanalysis – also referred to as code breaking, the process of undoing Cryptography
Encryption – converts “plaintext” into an encoded text or a “ciphertext”
Decryption – the reverse of Encryption
Cipher – algorithms used to encrypt and decrypt text
Key – an unknown parameter needed to operate a particular cipher’s algorithms
Also known as single-key, private-key, one-key and secret-key
Method of encoding where both the sender and receiver of a message hold the same key which is needed to decode the message, and involving the use of block ciphers and stream ciphers.
Encoding through Block Ciphers – Uses a fixed-length groups of bits, known as a block. Will take a plaintext as an input and using a secret key encode the text, and output ciphertext of the same bit size as the input
Encoding through Stream Ciphers - plaintext digits are encrypted one at a time, with the transformation of successive digits varying during the encryption
Uses a widely distributed public key used for encoding the message, and a different key, related mathematically to the former, used for decoding which is kept secret
More secure than Symmetric-Key Cryptology because the receivers private decoding key is never made known reducing the chance that it may be copied in transit