Optimizing iSCSI storage network: A direct data transfer scheme using connection migration

Abstract

This paper describes the design and performance evaluation of direct data transfer scheme between client applications and storage devices in iSCSI storage area network based distributed file systems. This is done by using ?TCP-Migrate Option? for establishing iSCSI session between server and storage devices. Migration enabled TCP connection is migrated to client machine for providing direct data path between client and storage device. This connection migration is completely transparent to the applications on client, server and storage devices. We evaluate the architecture using distributed file system NFS, but approach is flexible enough to be integrated with any distributed file system. The analytical model and qualitative analysis suggest this approach improves the scalability (by removing server as a bottleneck) and performance (through shorter data paths) and is especially useful for fast delivery of streaming media and file transfer applications.