Patent ID: 8553889

Claim:
A participant encryption apparatus, comprising: a key encryption processor that encrypts one secret key in a plurality of secret keys of secret key cryptography using one public key of a plurality of public keys, wherein each public key corresponds to one of a plurality of substitution/decryption apparatuses; a data encryption processor that encrypts given data using one secret key in the plurality of secret keys; a hash value encryption processor that calculates a hash value of the given data by using a cryptographic hash function and encrypting the hash value by one public key in the plurality of public keys; a processor that provides plaintext as a first input to said data encryption processor and subsequently and repeatedly inputs data to said data encryption processor, wherein the data is provided from preceding outputs from said data encryption processor, said key encryption unit processor, and said hash value encryption processor, wherein the processor inputs the plaintext and data to said data encryption unit processor a number of times equal to the number of substitution/decryption apparatuses; and a transmitter for outputting encrypted data from said processor.