Faster Fibre Channel on Tap

4g-bit, 10g-bit will be aimed at different markets.

Fibre channel is being primed for not one but two huge performance boosts in the not-too-distant future, as it jumps from 2G-bit to 4G-bit and, eventually, 10G-bit Fibre Channel systems.

More connections on the way

Going into next year, IT managers will have more SAN connection options than ever before. Here is a list of the four primary technologies and their likely uses.


10G-bit Fibre Will be used as ISLs, especially in Channel director-class switches; will make its way into high-end servers within the next few years

4G-bit Fibre Will become the new high-performance

Channel interconnect linking enterprise-class servers and storage to SAN switches

2G-bit and 1G-bit Current standard: will continue to link Fibre Channel low-end servers and storage to SANs

iSCSI Will continue as the leading low-cost SAN network connection, allowing inexpensive servers and workstations to hook into SANs

Although it might seem like an afterthought, given that most IT managers (and even some hardware vendors) are actively planning for 10 Gigabit Fibre Channel, eWEEK Labs believes the emergence of 4G-bit Fibre Channel will still wind up being an important technology during the next year.

Earlier this summer, the Fibre Channel Industry Association voted to support the 4G-bit Fibre Channel standard in interswitch fabrics. This is a big step because 4G-bit technology was previously geared for use only as an internal connection for storage devices (such as connecting disk drives to arrays).

Based on our talks with major vendors, virtually all Fibre Channel switch vendors are going to support 4G-bit Fibre Channel hosts.

4G-bit Fibre Channel technology, including HBAs (host bus adapters) and switch ports, will be priced comparably to current 2G-bit Fibre Channel solutions and will maintain backward compatibility with 1G-bit and 2G-bit Fibre Channel. Backward compatibility will not be available between 10G-bit Fibre Channel and the older versions.

Given its backward compatibility and price point, 4G-bit Fibre Channel is poised to become the dominant interconnect for connecting servers and storage units to Fibre Channel switches. We expect to see 4G-bit Fibre Channel HBAs and switches with 4G-bit ports later this year.

10G-Bit Fibre Channels Fit

In its first phase of rollout, 10G-bit Fibre Channel will be primarily used in ISLs (Inter Switch Links). A clear example of this is Sanera Networks Inc.s DS10000 Datacenter-Class Director switch, which is in beta tests and already has 10G-bit Fibre Channel blades.

10G-bit Fibre Channel should make topologies of enterprise SANs (storage area networks) easier to set up and manage. For example, instead of using five 2G-bit links to hook two switches together, a single 10G-bit link will be able to carry the load.

Given the current state of server hardware (server buses and processors are not fast enough to saturate HBAs), we dont expect to see 10G-bit Fibre Channel versions soon.

PCI-X 2.0 266, which will support 2GB-per-second throughput, should have the sheer performance to make use of 10G-bit Fibre Channel HBAs, but compliance testing for PCI-X 2.0 is just starting now. (Tests begin next month.)

When faster buses become available in the next one to two years, 10G-bit Fibre Channel will be attractive to specific markets such as video production and high-speed backup, where throughput is extremely important.

Senior Analyst Henry Baltazar can be reached at henry_