The 32-bit, 33MHz PCI generally delivers about 80 to 100 Mbytes/second sustained transfer rate but the base goals for Nexsan's RAID product were way above that. With this in mind, it was clear that an off-the-shelf solution was unlikely to make the stated performance or scalability goals.
Serverless backup is a simple, elegant solution to the problem of how to safeguard massive and exponentially growing amounts of data without compromising system performance or limiting the bandwidth available for enterprise communications. It is therefore important that the backup system can support the SAN directly, otherwise it could force data to travel from SAN-based storage via a file server on the LAN just to enable the backup software to write the data to tape. In such cases, the file server would act as a bottleneck, slowing down the backup process and once again threatening the backup window.