Ethernet zooms to 100 Gigabit speeds

How fast can data travel over Ethernet? If you answered 10 Gigabit per second, then you would be off by about 90 gigabits per second. Infinera, a San Jose, Calif.-based start-up, along with University of California, Santa Cruz, Internet2 and Level3 Communications, today demonstrated a 100 gigabit/second Ethernet connection that could carry data over a 4000 kilometer fiber network. The trial took place at the Super Computing Show in Tampa, Florida.

The experimental system was set up between Tampa, Florida and Houston, Texas, and back again. A 100 GbE signal was spliced into ten 10 Gb/s streams using an Infinera-proposed specification for 100GbE across multiple links. The splicing of the signal is based on a packet-reordering algorithm developed at the University of California at Santa Cruz. This algorithm preserves packet order even as individual flows are striped across multiple wavelengths.

A single Xilinx FPGA implements this packet numbering scheme and electrically transmits all ten signals to ten of Finisar’s 10 Gb/s XFP optical transceivers which in turn convert the signals to optics. These signals are then transmitted to an Infinera DTN DWDM system.

These packets which have a special sequence numbering are then reassembled by the receiver. In short, Infinera has bonded 10 parallel 10 Gb/s channels into one logical flow while maintaining packet ordering at the receiver. (Services that combine multiple wavelengths to offer a single service are referred to as super-lambda services.)

The trial shows that seriously high speed services can be offered over existing 10 Gb/s transport networks. “Gigabit Ethernet will be a critical technology to accommodate bandwidth growth, and this demonstration shows that we have the capability to implement this as a super-lambda service over today’s networks,” said Infinera co-founder and CTO Drew Perkins.

It was about 14 months ago we wrote about the 10 GB/s network that connected the University of California, San Diego and NASA Goddard Space Flight Center over a dedicated optical path. We chatted with Perkins earlier today and he said that the trial today shows that you can build scalable systems that can achieve higher speeds. “The way bandwidth demand is growing right now, we need 100 Gb/second now,” he says. “The network is going to keep growing.”

The IEEE has set up a Higher Speed Study Group (HSSG) group and is looking for specifications for higher speed Ethernet. The 10 GbE took about five years to become a standard, but the working group might have to hurry this time around. Proliferation of higher speed consumer connections, and emergence of video over IP will make 100 GbE a must have for most carriers.
While the 100 GbE technology is unlikely to show up in your neighborhood anytime soon, the trial is an important step in addressing the ever growing demand for bandwidth. The technologies like the one demonstrated by infinera and its partners will first show up in long haul networks. The largest IP backbones are currently using multiple 10 Gb/s links between core sites.

The online video explosion is going to tax the current fiber and network infrastructure, and will fill up the networks rather quickly, officials at Level 3 explained, when we met with them last week at the Web 2.0 Summit in San Francisco.