The security of the cryptographic techniques heavily relies on strong encryption and decryption algorithms and increased complexity associated to the algorithms. In this book the plaintext message is converted to the ciphertext message by using both RSA as asymmetric key algorithm and one-time pad as symmetric key algorithm. Three levels of encryption processes are imposed to produce a ciphertext which for sending to the receiver. First, the original message is encrypted by the private key of RSA algorithm of the sender then the output of the first encryption is again encrypted with the...