Since IP-SAN allows us to reduce initial costs and management costs of storage by using IP networks, iSCSI, common protocol in IP-SAN, is becoming more important. Although one of the key issues for iSCSI is a security measure to access remote storage over IP networks, this is not necessarily established yet. iSCSI can employ IPsec that offers a function of strong encryption. However, the IPsec encryption processing degrades throughput of storage access and increases its CPU load. In addition, it is difficult to execute encryption processing efficiently, because IPsec layer is located in a lower-level.

In this paper, we implemented a middleware system of executing encryption processing in the upper-layer for the communication using iSCSI securely and effectively. Moreover, we simulated the idea of optimization of encryption processing and evaluated its performance by running parallel processes in a long-latency network. As a result, optimazation method of encryption processing is more efficient than that of IPsec in a long-latency network.