iSCSI has a problem of drastic performance deterioration in the case of longer-latency. Thus, we have optimized iSCSI remote storage access through multiple layers. As a result, when RTT is 32ms, performance of the optimized iSCSI has achieved quadruple of that of the default iSCSI. Moreover, we have constructed the model of iSCSI sequential access and analyzed the factor of iSCSI performance deterioration.