Magazine Article | July 1, 2001

How Do You Want Your Speed?

Source: Field Technologies Magazine

Fibre Channel, Gigabit Ethernet, iSCSI, or InfiniBand - how will you decide? You may have the need for data transfer speed, but infrastructure and interoperability are just as important.

Integrated Solutions, July 2001

Fibre Channel technology made SANs (storage area networks) possible. SANs enable companies to pool their storage resources and make them accessible to many users. Many companies have been willing to pay a premium for Fibre Channel. But Fibre Channel has several other technologies nipping at its heels these days that will not only make SANs possible, they'll bring them downstream from large enterprise applications to small- and medium-sized businesses.

IT managers know SCSI (small computer system interface), which is celebrating its 20th year. Ethernet has become a well-known standard, too. When Fibre Channel came along, proponents of both SCSI and Ethernet technologies decided to fight rather than roll over and die. Fibre Channel enjoyed a short period of admiration before storage over IP (Internet protocol) standards using SCSI protocol were developed and called iSCSI. In addition, Ethernet is evolving into Gigabit Ethernet, working toward a 10-gigabit standard. But the FCIA (Fibre Channel Industry Association) has been working on survival tactics of its own in the form of a 10 GFC (Gigabit Fibre Channel) standard.

Upcoming 10 GFC Standard Gives End Users More Choices
Steve Garceau, product manager at CMD Technologies (Irvine, CA) adds, "The 10 GFC standard will give end users more choices because Fibre Channel and optical share the same wires. The bigger issue will be the protocols that the different technologies speak. You'll see devices being multilingual and multiprotocol. These devices will not only be able to speak Fibre Channel but also iSCSI and others."

"The completion of the 10 GFC core content, which includes multiple technology roadmaps, leverages the work done by the IEEE P802.3ae Task Force and shares a common link architecture and components with Ethernet and InfiniBand," states FCIA Chairman Skip Jones. "We are on schedule, and the final standards to provide 10 GFC links to the installed base of Fibre Channel implementations are expected to be ready in early 2002."

Most Fibre Channel applications are configured at 1 Gb/s (Gigabit per second) but many 2 Gb/s are currently shipping. According to the FCIA, the 10 GFC standard takes into account compatibility for investments made in today's 1 Gb/s and 2 Gb/s Fibre Channel implementations, sharing the same common link services and specifications. Also, users will have to be concerned with only one physical infrastructure for multiple network applications. Fibre Channel and Ethernet today share the same optical 1 Gb/s specification, cables, and transceiver infrastructure. In the same way, Fibre Channel, InfiniBand, and Ethernet will all share the same physical transmission infrastructure.

Garceau observes that iSCSI, which works over Ethernet connections, is picking up steam but thinks that Fibre Channel can be an important part of that. "There's a lot of talk about routers and bridges converting Fibre Channel SAN block storage so they can talk the IP over regular Ethernet. I have no doubt that Ethernet will get to 10 Gb before Fibre Channel will. The big thing with Ethernet is that the wiring is already there. The IT support guys already know how to deal with it. They know its limitations, and it is less expensive than Fibre Channel. But there's a benefit to bridging Fibre Channel SAN islands with IP-based SCSI block transfers."

FCIA Driving To Better Standards
Matt Carr, director of strategy and planning for Crossroads Systems, Inc. (Austin, TX) agrees. He says the biggest issue with 10 GFC is not speed. "If we listen to the end users' concerns as an industry, going faster is not necessarily their top concern. They want ease of implementation, easier management, better operability, and consolidated management. The management software from both the device management and the data management sides must have better standards and interoperability. The FCIA is driving toward that."

At the same time the FCIA is driving toward better standards and interoperability, it is again looking to the future, not stopping at 10 GFC. With its sights set on 2010, it expects to develop a 100 GFC standard by then. But Carr cautions IT buyers to look for interoperability, industry standards, data management, and backup tools. "There will be a lot of new technology developed around 10 GFC and 10 Gb Ethernet," he said. "And InfiniBand will help cluster servers and scale infrastructure. All of those things are coming. As end users look for solutions and decide to implement sophisticated storage solutions like SANs, it's important to crawl before they run."

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