A peripheral device includes: an input/output block connected to a device subject to connection; a communication block configured to communicate with a device subject to communication; and a conversion block configured, if the device subject to communication is a storage device, to convert a storage access command output by the device subject to connection to the input/output block into a communication command that is transferred between the communication block and the device subject to communication, wherein the communication block transmits the communication command generated by the conversion block to the device subject to communication and transfers, with the device subject to communication, one of data that is written by the device subject to connection to the device subject to communication and data that is read from the device subject to communication.