Data to be encrypted is effectively encrypted by a data delivery system for encrypting the data to be encrypted with a transmitting apparatus and decrypting a cipher thereof with a receiving apparatus. In a configuration for encrypting and decrypting the data to be encrypted by using a random number sequence generated by a random number generating portion for generating the random number sequence uniquely decided from an input parameter, the transmitting apparatus generates the input parameter to perform encryption based on metadata of the data to be encrypted while the receiving apparatus generates the input parameter to perform cipher decryption based on the metadata embedded in the data to be encrypted.