A fault tolerant storage subsystem includes a first tier of failure independent data storage units coupled to a storage controller, and a second tier, including at least one failure independent data storage unit, coupled to at least one of the failure independent data storage units in the first tier...http://www.google.fr/patents/US6289471?utm_source=gb-gplus-shareBrevet US6289471 - Storage device array architecture with solid-state redundancy unit
Storage device array architecture with solid-state redundancy unit
