Patent ID: 7949806

Claim:
A method to provide operations to an information storage device, comprising the steps of: supplying a data storage and retrieval system comprising a system controller in communication with a host computer comprising a storage management program, and a data cache; supplying a protocol conversion device in communication with and external to said system controller, wherein said protocol conversion device comprises a processor and a data queue and is capable of converting an operation from a first communication protocol to a second communication protocol, wherein said first communication protocol comprises a variable attribute, and wherein said second communication protocol does not comprise said variable attribute; supplying an information storage device capable of communicating said second communication protocol but not said first communication protocol, wherein said information storage device is external to and interconnected with said protocol conversion device; generating a plurality of operations by a host computer in communication with said data storage and retrieval system, wherein each operation is selected from the group consisting of a read command and a copy command, and wherein each operation is associated with a priority selected from a plurality of priority levels; providing said plurality of operations from said data cache to said protocol conversion device using said first communication protocol; generating an operation number for each of said plurality of operations by said protocol conversion device, wherein each operation number comprises a time stamp representing a time said protocol conversion device received an operation; enqueuing said plurality of operations in said data queue; sending from said data queue to said information storage device by said protocol conversion device an enqueued operation having a highest priority level; determining by said protocol conversion device if said variable attribute is configured in said enqueued operation; operative if said variable attribute is not configured in said enqueued operation, providing said enqueued operation by said protocol conversion device to said information storage device using said second communication protocol; operative if said variable attribute is configured in said enqueued operation, implementing said variable attribute by said protocol conversion device when providing said enqueued operation to said information storage device using said second communication protocol.