The storage regions under command of a storage controller can be simply enabled and disabled to access to by automatically registering connected host computers. Such system can be achieved by taking a step of acquiring N_—Port_—Name information included in a login frame from the host computers, and a step of displaying a table of access right of host computers to a logical unit under command of storage controller. A security table for the storage controller can be generated by supervisor's setting the access enable/disable flag information.