Start-up Zetera promises storage revolution
SANs without iSCSI, Fibre or RAID - can that be right?
By Chris Mellor | Techworld | Published: 14:27, 13 January 2005
Storage networks without using Fibre Channel or iSCSI or RAID or disk controllers - that is what start-up Zetera is claiming, and it has already signed up Netgear and StorCase to sell its new technology.
The set-up works as follows: drives in Zetera-architecture boxes are linked via Ethernet to host servers. IP Multicast protocol is used to control data I/O to the drives. This sends a message simultaneously to all the drives in a Zetera array. Each drive has an protocol converter circuit card to translate IP packets to disk drive communications.
The drives in the Zetera array are virtualised into virtual storage volumes each with their own IP address. High performance comes from striping data across drives and communications channels to them.
No use of TCP means no need for TCP/IP Offload Engines (TOEs) - needed for good performance in iSCSI SANs. No use of Fibre Channel means no HBAs. Virtualising drives paves the way for drive mirroring, files spanning drives, and RAID functions. IP Multicast to a Zetera array means you can have NAS functions without needing a NAS server.
Zetera claims [pdf] its architecture, using block-level technology, delivers near line speed storage for a fraction of either SAN (iSCSI or Fibre Channel) or NAS cost because of this component simplification. It also claims its architecture scales virtual storage volumes linearly without any need for special controlers or aggregators. It also claims it provides a virtual RAID structure with the performance of a hardware RAID but needing no actual RAID controller.
The actual drives used can be ATA, SATA, SCSI or Fibre Channel: it doesn't matter as long as there is an Ethernet IP connection to them. Host servers merely need Ethernet NICs. The interactions between servers and drives are IP and session-less, so less processing power is needed. Standard Ethernet switches are used and can multiply bandwidth.
Zetera OEMs Storcase and NetGear will deliver Zetera-based storage in the spring, aiming at medium and smaller enterprises. The StorCase systems incorporate fault-tolerant technologies like redundant power supplies, multiple-gigabit Ethernet ports and removable hard drives, depending on the model.
As such, the user will be able to configure the storage array to provide a variety of information protection capabilities including striping for faster performance, mirroring to protect data from potential drive failure, and spanning to allow the creation of logical drives with unlimited storage capacity.
It sounds almost too good to be true: SAN, NAS and RAID functionality with no need for HBAs, TOEs, NAS servers or Fibre Channel fabrics. There are no research or technology analyst reports available as yet though, so we have no independent authoritative accounts of the architecture and its benefits.
Zetera was founded in 2002 by an ex-Western Digital chief technology officer and one of his engineers plus an entrepreneur. Have they got it right? We'll let you know just as soon as we know.