Who needs dense 10 GbE switches?

Ethernet vendors are plugging port density as the new must-have. But even if you are virtualizing heavily do you really need a switch with so much power?

There is a horserace developing in the networking industry for port density in 10 Gigabit Ethernet switches, particularly in data center network core switches. But when it comes to squeezing the most ports into a single chassis, only the Facebooks and Googles of the world are paying particularly close attention. The question is: When should the larger population of network engineers begin to care?

This month, data center network switch specialist Force10 Networks pushed port density in 10 Gigabit Ethernet (GbE) switches to new heights by announcing a 40-port line card for its half-rack E-Series ExaScale switch/router chassis. This card establishes Force10's network core switch density at 560 10 GbE ports in a single chassis.

Force10 now leads all of its competitors in terms of 10 Gigabit Ethernet switch port density, according to Kevin Wade, senior director of product marketing at Force10. Cisco's Nexus 7018 and 3Com's H3C S12518 both top out at 512 ports per chassis. It's also worth noting that the H3C chassis is twice as big as the Force10 E-Series network core switch, which means it will eat up a lot more rack space and power.

"Everyone wants to squeeze more stuff into less rack inches," Wade said. "It's part of that one-upmanship. "

Port density in 10 Gigabit Ethernet switches: If you build it, will they come?

Despite the heated vendor showboating, most companies in the mainstream data center networking world don't yet need this port density in 10 Gigabit Ethernet switches.

"Never say never, but it seems this density would be unnecessary for a company of our size," said Jim Prevo, CIO of Green Mountain Coffee Roasters. "We have around 200 servers in total today… in three different data centers. To use this type of density, I would need to plug every disk drive directly into the network, which might be someone's plan for SAN storage in the future, but it isn't on my radar screen at this point."

Force 10's target audience lies in companies like Facebook, Yahoo, Internet farms, banks and others that depend on sending massive amounts of data, according to Zeus Kerravala, distinguished research fellow for Yankee Group.

"It's like saying, does everyone need a supercomputer? Not most enterprises. But those that do, actually take advantage of it," Kerravala said.

This kind of density in 10 Gigabit Ethernet switches will eventually appeal to mainstream enterprises, according to Steven Schuchart, principal analyst at Current Analysis. But first, the cost per port will have to fall. And the scale of that density won't necessarily be as important as simply being able to fit more ports on a line card for a smaller class of network core switches than Force10's chassis.

"Will there be a time when 10 Gigabit is a lot more common in smaller enterprises? Yes," Schuchart said. "Density is important to them. A guy might not need the top-end switch that this [Force10] line card is for, but they might buy it in [a smaller chassis]. Getting the most 10 Gigabit ports possible in a switch is important. Density is money when it comes to these modular switches. As the price of 10 Gigabit begins to fall, density will begin to matter in businesses that are not in the high top-end."

Virtualization, the cloud and converged fabrics will boost interest in 10 Gigabit Ethernet switch port density

Virtualization and cloud computing uptake will drive interest in high-density 10 Gigabit Ethernet switches, Kerravala said, especially as enterprises push the boundaries of what they can do with virtual machine migration features found in products like VMware's vMotion.

"Right now, a lot of companies do have that density, but they don't have it at 10 Gigabit," he said. "If all of a sudden you need more, faster connections, then you're going to want to upgrade your Gigabit connections to 10 Gigabit connections, and that's going to drive that need for speed in the core."

It'll take a while, but as smaller enterprises move into virtualization, high-density 10 Gigabit Ethernet will move downstream, Kerravala said.

"The line in the sand where Force10 sells to their target market is shifting," he said. "There are a lot more companies that rely more on their networks as they start using the more advanced features of virtualization and try to automate a lot of data center processes. That will drive up the need for density."

Convergence of storage on data center networks, via converged enhanced Ethernet or data center bridging, will also boost interest in 10 Gigabit Ethernet port density in network core switches, according to Schuchart.

"If you're converging storage onto Ethernet, 10 Gigabit is the place to do it. I wouldn't bother converging Fibre Channel on Gigabit Ethernet," he said. "It would speed up the adoption rate, although I would say virtualization is a bigger driver than storage."

Read more on Data centre networking