TCP Congestion Window Control on an ISCSI Read Access in a Long-Latency Environment.

As the broadband networks are widely used, IP-SAN is expected as the next generation’s SAN because of its low cost. The iSCSI protocol, represented as IP-SAN technology, is becoming increasingly important. However, the performance of iSCSI network is lower than that of network based only on TCP/IP, due to its complex protocol processing in accessing storage with iSCSI. In this paper, we present performance improvement using a dynamic Congestion Window control method to stabilize throughput unevenness. We evaluated iSCSI network performance with a remote storage access on iSCSI protocol using the proposed method. As a result, iSCSI performance improved compare with the case of not using the proposed method in a long-latency environment, and we confirmed the proposed method is effective.