Coraid has produced what it claims is the cheapest ever storage network.

The EtherDrive series provides, among others, an Ethernet SAN with 7.5TB for just 53 cents per gigabyte. It uses ATA-over-Ethernet (AoE) protocol to send ATA drive commands and ATA data packets between servers and a serial-ATA drive array.

There is no need for a TCP/IP offload engine (TOE) because TCP/IP isn’t used and neither is SCSI. Instead an AoE driver in a server’s operating system turns ATA drive commands into messages to be sent over an Ethernet link, through an Ethernet switch, to a Coraid drive array fitted with an Ethernet interface.

The system will work with Linux, Solaris and other Unix operating systems but not Windows at the moment, although that is "coming soon" the company said.

Coraid CEO Jim Kemp said of the cost of this system: "Adding an Ethernet network connection to a SATA disk used to cost between $2.00 and $6.00 per gigabyte and Fibre Channel SANs cost a lot more than that.

"Our 15-disk EtherDrive Storage Appliance holds up to 7,500GB of disk storage and sells for $3,995 - or just $0.53 per gigabyte. Large capacity SATA disks prices range between $0.43 and $0.74 per gigabyte. Standard Ethernet switches are inexpensive, and the AoE protocol is free. Add it all up and the total system cost is less than $1.35 per gigabyte."

There are no performance comparisons on either data I/O rate or server CPU cycle take-up. Our intuition suggests that EtherDrives will have a lot less impact on a server than iSCSI. Being Linux-based - the AoE driver code is open source - users should expect a do-it-yourself element to setting the product up.