Subscriber registration and authentication method

Abstract

The present invention provides a subscriber registration and authentication method which secures high safety and by which necessary circuit scale is small. In the method of the present invention, each network termination unit has a peculiar secret information item for identifying it and an encrypted information item obtained from the secret information item with a public key determined by the network manager; the operation system decrypts the encrypted information item stored in the network termination unit which will be registered with a secret key determined by the network manager, and registers this termination unit for the local service unit by writing the encrypted and decrypted information items into the service unit; at the beginning of providing the service, the local service unit calls the network termination unit as a communication partner by sending the encrypted information item which is peculiar for the termination unit; the called network termination unit compares the received encrypted information item with that of its own, and if these agree with each other, responds to the local service unit by using the secret information item of its own; and the local service unit confirms that the network termination unit has been regularly registered by collating the received information item with the information item of its own.