Nortel demos passive optical networking

In the future, according to Nortel, optical networking provides 100-megabit-per-second dedicated communications pipes to homes and businesses, people hold business meetings in virtual worlds and high-speed wireless technologies provide high-definition video, voice and internet connectivity all at once.

Each year, Nortel Networks Corp. invites customers to its research and development facilities outside Ottawa for demonstrations of technologies that are in its labs or have recently emerged from them. Last year about 50 customers visited during the three-week Advanced Technology Summit, says Steve Foster, director of portfolio management at the Ottawa labs.

This year’s demo included wavelength-division multiplexing over fibre to homes and businesses.

Passive optical networking (PON) makes fibre to the home or business more practical because the outside plant is simple and connections to the central office are easier to manage, says James Goodchild, product line manager for Nortel’s Ethernet fibre access business, but it means customers share bandwidth and it can be hard to upgrade. Nortel’s answer is PON using wavelength-division multiplexing rather than the usual time-division multiplexing.

Rather than sending packets of data to different customers over shared wavelengths, wavelength-division multiplexing allocates each of 32 wavelengths on a fibre to one customer exclusively. This means Nortel can deliver an Ethernet connection directly to the home or business.

Useful for wireless backhaul

The technology is capable of 100-megabit-per-second speeds today, Goodchild says, with potential to grow to one gigabit in the future. Besides business and residential use, it can be used to backhaul wireless services, Nortel says.

The termination devices are easy to install, configuring themselves to the proper wavelength automatically, and can be swapped with almost no disruption to service.

Nortel demonstrated the system to reporters at its Ottawa lab delivering video, internet access and voice. It has been deployed in Korea and a carrier in the Netherlands has announced plans to use it, Goodchild says.

While fibre to the home is still too costly for most North American carriers, says Jon Arnold, a Toronto consultant and principal of J Arnold & Associates, Verizon is pursuing it in the U.S. Economic turmoil makes its immediate future more uncertain, he adds. “You’re only going to build fibre if you think customers are willing to pay.” However, Goodchild says Nortel has seen significant interest in residential use of the technology.

But Nortel is betting on other network technologies too, including wireless ones. The company is showing off similar applications to those its PON system can support running over Wi-MAX, the faster, wider-range relative of Wi-Fi wireless networking.

WiMAX is an option both for mobile services and for delivering broadband to areas not economically served by existing wireline technologies, says fourth-generation product marketing specialist Niloufar Tayebi.

It will be able to deliver voice over Internet Protocol, internet access and streaming video, she says. One advantage of WiMAX over Wi-Fi is that it uses licensed spectrum and can provide quality-of-service capabilities. Nortel’s demo includes loading a network with traffic until it becomes congested enough to slow down video feeds, without affecting the quality of a voice conversation thanks to the QoS capabilities.