Patent ID: 6910020

Claim:
A network transaction system in which a customer's terminal station is connected to a first bank system via an open network and the first bank system is connected to a second bank system via an inter-network, the customer having an existing bank account in the second bank system and attempting to newly open a bank account in the first bank system, the network transaction system comprising: customer processing means disposed at the terminal station and coupled to the open network, said customer processing means for applying for a new bank account by supplying via the open network the first bank system with existing account information descriptive of the existing bank account owned by the customer in the second bank system; first bank processing means disposed at the first bank system and coupled to the open network and inter-networks, said first bank processing means for requesting via the inter-networks the second bank system to make a confirmation of the existing bank account while forwarding the existing account information received from the customer processing means to the second bank system over the inter-network, and for opening the applied new bank account based on a confirmation response message received via the inter-network from the second bank system describing a result of the confirmation of the existing bank account, wherein the first bank processing means authenticates the customer based on the confirmation; and second bank processing means disposed at the second bank system and coupled to the inter-network, said second bank processing means for confirming validity of the existing bank account upon request from said first bank processing means, and for returning the confirmation response message to said first bank processing means to report the result of the confirmation of the existing bank account, wherein said customer processing means comprises: (a 1 ) customer key generation means for generating a customer secret key and a customer public key, (a 2 ) customer encryption means for assembling an account application message to be sent to said first bank processing means by: encrypting account application information necessary for opening the new bank account by using the customer secret key and further by using a first bank public key, encrypting the customer public key and a second bank identification code by using the first bank public key, encrypting the existing account information by using the customer secret key and further by using a second bank public key, and combining the encrypted account application information, the encrypted customer public key, the encrypted second bank identification code, and the encrypted existing account information, and (a 3 ) customer decryption means for obtaining new account acknowledgment information by decrypting an application response message received from said first bank processing means by using the customer secret key and further by using the first bank public key.