A disk controller has a front end FC I/F to a host, a back end FC I/F to a magnetic disk, a processor, and a main memory section. The front end I/F and the back end I/F are provided for performing information exchange with a network (connected) device that is connected to a network and manages storage. The main memory section stores registered information expressing an attribution of the network (connected) device, access information including the security and the performance of each network (connected) device through the network, and ranking information assigning a rank to each network (connected) device based on the registered information and the access information. An appropriate network (connected) device is selected from various types of information including the ranking information.