Diffie-Hellman key exchange

[tevinjoseph]

Diffie-Hellman was the first public-key algorithm ever invented, way back in 1976 . It gets its security from the difficulty of calculating discrete logarithms in a finite field, as compared with the ease of calculating exponentiation in the same field. Diffie-Hellman can be used for key distribution—Alice and Bob can use this algorithm to generate a secret key—but it cannot be used to encrypt and decrypt messages.