In June, FCoE passed a major milestone after being approved by the FC-BB-5 group of the T11 Technical Committee -- and the technology is now well on its way to being confirmed by INCITS as an ANSI standard.
With FCoE, organisations will be able to use Ethernet cabling for both data centre network and storage traffic, potentially doing away with the need for separate Fibre Channel (FC) fabrics. FCoE does this by encapsulating Fibre Channel frames so they can run over Ethernet. Fibre Channel is built to guarantee lossless delivery of frames with a predictable latency and FCoE brings these qualities to the normally inherently less-reliable Ethernet environment.
As well as halving the amount of cable required, putting everything onto a common Ethernet network makes it possible to replace multiple network interfaces and host bus adapter (HBA) cards with a single converged network adapter (CNA). The CNA handles both protocols on devices that communicate across 10 Gig links, but at the same time enables storage and network domains to be controlled independently.
With fewer cards, network devices and cabling needed, the potential exists to cut equipment, management and maintenance costs, and to bring a reduction in power and cooling requirements. FCoE will provide a way of rationalising a complex data centre infrastructure, while enabling the continued use of existing Fibre Channel management tools and skills.
Martin Taylor, converged network manager at the Royal Horticultural Society (RHS), explained it this way: "The benefits are that equipment costs should be cheaper as FCoE runs on Ethernet kit -- but because it's not part of TCP/IP, the reliability of the connection is higher. So it's about higher performance at a lower cost, and it should bring Fibre Channel to people that can't currently afford it."
Who is deploying FCoE in the UK today?
Although many vendors have pre-standard Fibre Channel over Ethernet equipment available, enquiries with vendors and analysts in London indicate no production deployment to date -- even among existing Fibre Channel users in big enterprises. That's approximately 40% of local storage implementations, according to a SearchStorage.co.UK survey of users earlier this year. For example, Cisco Systems replied to a recent inquiry by saying there are no live FCoE deployments yet in the UK -- however, the company is expecting some in the next few months.Still, some UK analysts believe the technology is unlikely to move into the mainstream for at least five years.
Andy Holpin, a principal consultant for services at Morse Group, points out that one of the things in FCoE's favour is that Ethernet has won most of the battles it has so far fought against rivals such as Token ring, a local-area network (LAN) provider. Therefore, the likelihood is that it will eventually win the storage battle, too. "But it won't happen overnight, due to the current economic climate, which means that people won't want to invest much money in an unknown quantity for the time being," Holpin said.
Rather than big-bang deployments, uptake is instead likely to be part of infrastructure refresh cycles or moves to new data centres. However, adoption is expected to start rising in approximately 18 months as products become more widespread and mature. "Core systems move slowly, so most people wait for a natural upgrade and that cycle is different for each organisation," RHS' Taylor said. "But when they come to add more capacity, for example, there's no reason not to have mixed systems."
Taylor predicted that Ethernet hardware prices will continue to fall, and people will increasingly adopt FCoE. Over time, he added, "We'll see Ethernet infrastructure everywhere. It reduces cost, complexity and the skills needed to manage it, so I can see it being a leveler in the market into the long term."
Tony Lock, a programme director at analyst firm Freeform Dynamics, is not so sure. "Will FCoE be adopted? Yes. But will it take over life, the universe and everything? No. One of the big challenges at the moment is simply explaining where it fits. Vendors haven't done a very good job so far of explaining the business reasons for adoption."
User concerns with FCoE
One organisation that is yet to be convinced of the power of FCoE is mortgage and lending company Britannia Building Society. Although the company has already evaluated the technology and plans to do so again later this year, Unix and storage manager Dylan Mathias remains wary.
"There isn't a clear problem that it solves for us. We've got a lot invested in Fibre Channel and I can't see a distinguishing benefit -- so where's the motivation to change?" he said. "If you were a green field site, you might be able to balance the options, but it's more difficult to justify when you've got an existing investment. It's like saying why upgrade to high-definition TV if you're happy with the picture you've got?"
Mathias understands the cost-saving argument of having only one set of cabling, but he would have to rip out and replace existing infrastructure to make the change. Moreover, while looking after one network backbone rather than two might simplify management, his team is already familiar with FC technology so there's no pinch on skills to deal with.
These types of considerations are likely to act as inhibitors to widespread adoption of Fibre Channel over Ethernet, at least in the near future. To switch to FCoE requires investment in new equipment and an upgrade to the currently expensive 10 Gigabit Ethernet (10 GbE) cabling. "Unless there are obvious, immediate money-saving benefits today, it's not a good time to be suggesting architecture change for the sake of it," Freeform Dynamics' Lock said.
Additionally, there are often internal 'political' hurdles to overcome. Storage and network teams are often quite separate -- and converging them as well as the infrastructure won't be a trivial matter for many businesses. At the very least, it will probably involve retraining personnel while also dealing with change management, which is invariably time-consuming and challenging.
The RHS' Taylor has reservations based on people factors. While not dismissing the technology out of hand, he said he would need to be seriously convinced that the pros outweighed the cons before considering Fibre Channel over Ethernet adoption, and that would include taking up reference sites.
"FCoE is definitely of interest for the future, and when we need to shoehorn in another connection to our own infrastructure we'll take a look at it," he said. "For now, though, we'll let the early adopters take it on first and learn from them."