The first 8Gbit/s Fibre Channel storage networking products are out, and could drive the final nail into the coffin of 10Gbit/s Fibre Channel. However, the new technology seems unlikely to stem the drift to iSCSI over 10Gbit/s Ethernet, although it might perhaps slow it a little.
8Gbit/s has the advantage that it uses the same infrastructure as 1, 2 and 4Gbit/s Fibre Channel - in fact, it is just the latest doubling of speed - and like 4Gbit/s and 2Gbit/s it is backwards-compatible. Speed matching allows 8Gbit/s devices to be added to existing SANs where they should interoperate, running each link at the highest speed that's supported by both ends.
The first 8Gbit/s products are promised by Emulex and QLogic. The technology will be available in the same formats as 4Gbit/s Fibre Channel - switches, host bus adapters (HBAs), etc - for just a 10 to 20 per cent price-premium, the companies suggested.
Users will see no change apart from extra speed, according to Emulex marketing veep Mike Smith. "When customers migrate, they'll experience a seamless transition, leveraging the same drivers and management applications. Our 8Gbit/s products have already achieved OEM design wins on multiple platforms."
A faster SAN technology has been around for some time in the shape of 10Gbit/s Fibre Channel, but it uses different cabling and was primarily for trunking between switches. The new 8Gbit/s spec should make it simpler and cheaper to tie switches together, as well as extending the faster speed to servers as well.
It should also score on virtualised machines, where several virtual servers are competing for the same HBA - as long as storage admins ensure it doesn't simply move the bottleneck from the HBA to the disk drive or array.
Most SAN users have not yet reached the limits of 2Gbit/s technology, never mind 4Gbit/s, but Enterprise Strategy Group analyst Brian Garrett said there are some who will welcome 8Gbit/s.
"Administrators of infrastructure applications like disk-to-disk replication and vertical business applications like video post-production are already asking for higher performance storage networks," he said. "The backwards compatibility of 8Gbit/s Fibre Channel will be warmly embraced in data centres, video production houses, and other application environments where performance counts."
However, in the wider SAN market, Fibre Channel has come under strong pressure recently from IP-based SANs such as iSCSI. The latter do not need a separate HBA in each server, and can more easily be extended over LANs and WANs.
Emulex and QLogic both said they are currently testing their 8Gbit/s hardware for delivery to their OEM partners for qualification. Shipments to end users could start early next year, they suggested.
Brocade and Cisco have not yet made public their plans for 8Gbit/s, but if the 4Gbit/s generation is anything to go by, they will not be in a hurry to add higher-speed products. ®