Startups Move 10-Gig to Copper
The "10-G Base T" study group hasn't set a timetable yet, but initial backers expect to complete the standard within the four-year window allotted by the IEEE. The group will be part of the 802.3 series of standards for Ethernet.
SolarFlare's pitch was backed by five other startups: Cicada Semiconductor Inc., Accelerant Networks Inc., Mysticom Ltd., Plato Labs, and Telicos. This clique won't necessarily be running the study group that the IEEE approved; those kinds of administrative details will be ironed out in the coming months.
"Our worst issue was the cynics," says Ahmet Tuncay, SolarFlare's founder and vice president of marketing. "Most people thought 10 Gbit/s could not be brought onto this type of cabling because it was beyond the Shannon wall" -- that is, beyond the theoretical limit of transmission speeds on a noisy channel.
SolarFlare's presentation -- which went into significant technical detail -- convinced the engineers in attendance that the feat was possible. "You just have to mitigate more of the capacity-reducing impairments like echo," Tuncay says.
The IEEE already addresses 10-Gbit/s Ethernet in its 802.3ae standard, but the new group's focus is on a deeper level. Specifically, they'll be discussing the electronics required to make 10-Gbit/s signals viable on existing copper wiring, as the noise levels on those cables can be enough to slow down or disrupt high-speed signals.
The goal is to make 10-Gbit/s Ethernet viable for the existing business environment without forcing companies to rewire their buildings with fiber.
"Unlike metro Ethernet, enterprise Ethernet has a legacy of working on installed cabling, and UTP [unshielded twisted pair] is the predominant flavor of cabling in these data centers," Tuncay says. "The real challenge of 10 Gbit/s in the enterprise has been to figure out how to make it run on this installed cabling."
It's worth noting that the six startups aren't in lockstep agreement on the standard. They all want to use technologies available today, such as pulse-amplitude modulation and adaptive equalization, but the specifics are up for grabs.
PAM, for example, is a way for electronic signals to carry more than one bit per pulse, but the startups disagree on which version of PAM should be used. With adaptive equalization -- the ability to compensate for the variations in signal quality -- it's a question of whether an analog or digital technique is best.
"These are the areas where the study group is going to spend some time," says Jim Tavacoli, vice president of marketing for Accelerant.
The study group's next step is to submit a Project Authorization Request to the IEEE. Once that's approved, the group becomes a "working group" and is officially on its way toward defining a standard.
— Craig Matsumoto, Senior Editor, Light Reading
Want to know more? The big cheeses of the optical networking industry will be discussing 10-Gigabit Ethernet at LightSpeed Europe. Check it out at http://www.lightspeedeurope.com.