An encryption scheme has five ingredients: Plaintext: This is the original message or data that is fed into the algorithm as input. Encryption algorithm: The encryption algorithm performs various substitutions and transformations on the plaintext. Secret key: The secret key Read More …

# Tag: An Overview of Cryptography

## Cryptography and Cryptanalysis is an important aspect of network security, Comment?

Cryptography: Cryptographic systems are generically classified along three independent dimensions: The type of operations used for transforming plaintext to cipher text: All encryption algorithms are based on two general principles: substitution, in which each element in the plaintext (bit, letter, Read More …

## DES is not a block cipher method of encryption method. State true or false and explain DES?

False, DES is a block cipher method. The most commonly used symmetric encryption algorithms are block ciphers. A block cipher processes the plaintext input in fixed-sized blocks and produces a block of cipher text of equal size for each plaintext Read More …

## Write Diffie-Hellman key exchange algorithm?

The first published public-key algorithm appeared in the seminal paper by Diffie The purpose of the algorithm is to enable two users to exchange a secret key securely that then can be used for subsequent encryption of messages. The algorithm Read More …

## Explain Block Ciphers as Hash Functions?

It can use block ciphers as hash functions using H0=0 and zero-pad of final block and compute: Hi = EMi [Hi-1]. Use final block as the hash value similar to CBC but without a key resulting hash is too small Read More …

## RSA algorithms is a milestone in the development of cryptography, Comment and Write its step?

Diffie and Hellman introduced a new approach to cryptography, and challenged cryptologist to design a general-purpose encryption algorithm that satisfies the public-key encryption requirements. One of the first responses to the challenge was developed in 1977 by Ron Rivest, Adi Read More …