A network storage system with a high transfer rate and high capacity has been developed. This system, DVD-RAIL (Digital Versatile Disk-Redundant Array of Inexpensive Libraries), consists of six small DVD-RAM libraries and a RAILcontroller, which uses the RAID4 algorithm. Each library has two DVD-RAM drives, a robotic changer and a slot for storing up to 150 DVD-RAM disks. The system can handle up to 900 disks, corresponding to about 2 TB of storage. Data transfer is done in parallel from and to each library, so the transfer rate is over 6 MB/sec. The redundant architecture of RAIL provides high reliability, enabling the system to continue working even if an error occurs in one of the libraries. The RAILcontroller controls all the allocation and parallel transmission processes, so the system behaves as a large single library. Evaluation of the system showed that it can distribute high- definition moving pictures at over 20 Mbps and that a transfer rate of over 50 Mbps may be feasible.