Patent ID: 8707010

Claim:
A switch that connects and disconnects an input and output control device to and from an input and output device, the switch comprising: a storage unit that stores therein a translation table for use in translating a physical address used on a virtual machine that a guest operating system specifies as a direct memory access transfer destination to the input and output device, into a physical address used on a real machine; an address translating unit that translates an address contained in a direct memory access request issued by the input and output device into a physical address used on the real machine by referring to the translation table; and an address-translation-table managing unit that, when the switch receives a request directed to the input and output control device from the input and output device, the request being to transfer a translation table to the input and output device to store therein and the requested translation table is not stored in the storage unit, the switch passing the request to the input and output control device, stores in the storage unit the requested translation table transferred from the input and output control device via the switch to the input and output device.