Patent ID: 7240139

Claim:
A storage system comprising: a plurality of channel interface units, each of said channel interface units having a host interface connected to a host computer, a first selector connected to said host interface, a second selector, and a first processor controlling said host interface, said first selector and said second selector; a plurality of disk interface units, each of said disk interface units having a disk interface connected to a disk device, a third selector connected to said disk interface, a fourth selector, and a second processor controlling said disk interface, said third selector connected to said disk interface, and said fourth selector; a first cache memory, connected to said first selectors and said third selectors, for storing data transferred between said host and said disk device; and a fifth selector connected to said second selectors and said fourth selectors, wherein said first processors and said second processors transfer control information through said second selectors and said fourth selectors and said fifth selector, and wherein said control information are used to control a transmission of said data among said first selectors, said third selectors and said first cache memory.