Patent ID: 8352649

Claim:
A storage virtualization subsystem (SVS) architecture comprising a plurality of SVSs, each of the SVSs comprising at least one storage virtualization controller (SVC) which comprises a device-side IO device interconnect controller implemented complying with a serial attached SCSI (SAS) protocol; a first data access path and a second data access path are configured passing through the SVSs to form the SVS architecture; wherein the two data access paths are configured in a way that the SVSs in the first path are connected in a first sequence and the SVSs in the second path are connected in a second sequence different from the first sequence, so that a data path redundancy of the first data access path and the second data access path is achieved, and when one of the SVSs is off-lined such that an SVS which is among the SVSs and which is behind the off-lined SVS, can not be accessed by the first data access path, the SVS which is among the SVSs and which is behind the off-lined SVS can still be accessed by the second data access path.