A gateway manages the right of a portable terminal to access data of various contents services stored in a contents server. When the gateway receives the first request for access from the portable terminal, it assigns a user ID and a password to the same and transmits them to the portable terminal. When another request for use added with the same ID and PW is received, the gateway generates access history information after authenticating the user and grants an access right during a predetermined effective period from the date of the first access. In response to an access during the effective period, contents data acquired from the contents server are transferred to the portable terminal. In the case of an access out of the effective period, the access is interrupted, and continuation of the access right is prompted by an access right continuation notice.