apublic encryption key it sends to Bob. a private decryption key that keeps carefully. Bob uses the public key to encrypt the message and pass it to Alice. Alice uses the private key to decrypt the message received . Key Generation Are two major"randomly" chosen prime numbers p and q. Note: n = p*q and φ=(p-1) * (q-1) D be a big integer"randomly" selected, first with φ. And the inverse of e modulo φ.
Public key encryption is the pair(n,e), the private decryption key the pair (n, d). ****Encryption /Decryption****
1- encryption
Before being encrypted, the original message must be broken down into a series of integers M values between0 and n-1.
For each integer M must be calculated C≡M^e[n].
The encrypted message is made up o fthe sequence of integers C.decryption According to how it was encrypted, the message will becomposed of a sequenceof integers Cvalues between0and n-1. For each integer C must calculate M≡C^ d[n]. The original message can then be reconstructed from the whole series M.
