Computer Science
Computer Catlog
Cryptography Catlog

Caesar Cipher
Digital Signature
Public key cryptography
Symmetric vs. public-key
Key Management
Stream Ciphers
Self-Synchronizing Ciphers
Feedback Shift Registers
Modes of Operation
Multiple Encryption
Transposition Ciphers
Substitution Ciphers
Poly-alpha Substitutions
Poly-alpha Cipher Machine
Cryptanalysis Ciphers
Data Encryption Standard
DES Algorithm
IDEA Algorithm
RC5 Algorithm
RSA Encryption
Rabin Encryption
ElGamal Encryption
MD4 & MD5
Secure Hash Algorithm
Kerberos Authentication
Diffie-Hellman protocols
Key Management Life Cycle

ElGamal public-key encryption

    The ElGamal public-key encryption scheme can be viewed as Diffie-Hellman key agreement in key transfer mode. Its security is based on the intractability of the discrete logarithm problem and the Diffie-Hellman problem. The basic ElGamal and generalized ElGamal encryption schemes are described in this section.

ElGamal Key Generation

ElGamal Public-Key Encryption

    Proof that decryption works. The decryption of Algorithm allows recovery of original plaintext because

ElGamal Algorithm Example