eDCO enables wavelength distances to be extended without the usual additional network planning and associated engineering costs that entails. Nortel CTO John Roese said: It requires no retrenching or new fiber for the move to 40Gbps.
He said Nortel originally unveiled eDCO in June 2005, initially for 10Gb networking on its Optical Multiservice Edge 6500 box, but he said the 40Gb version of the technology has only now reached maturity. We’ve got the chipsets and they’re functional chips not bricks, so we’ll be in full production at the tail end of this year, he said.
Nortel is not in the passive optical networking market, where optical technology cables and signaling are taken all or most of the way to the end user. However, Roese said the various flavors of PON (fiber-to-the-kerb, building, or home) all drive the requirement for greater bandwidths in the backhaul, which is where Nortel does play, and where eDCO fits. Equally, though we’re not fans of HSPA [3G technology in the GSM world], it too is driving the need for bandwidth in the backhaul network, he said.
While a move to 40Gbps in the aggregation and core layers of their networks is desirable for carriers, it represents a challenge in terms of the additional capex involved in expanding trenches and pulling new fiber to accommodate the greater speed. There are also technical challenges. The first is attenuation, or a decrease in signal strength over greater distances, which means adding amplifiers. However, using cascaded amplifiers to counter attenuation results in another impairment: dispersion, which is a broadening of the signal in higher-speed optical links due to the propagation of different wavelengths at different speeds. This is the problem eDCO seeks to address.
Roese was in London last week to spread the word to European telcos about eDCO. The optical market is consolidating, with Marconi out, while Ericsson hasn’t oriented the company yet, and Cisco’s not focused on it, he said. We’re one of the few vendors that still has a research capability in optical.
