Year in review 2011: 100G optical takes flight

The news: A growing base of service providers decided throughout 2011 to sidestep a migration to 40G and go straight towards 100G in their core IP and optical network infrastructure.  

So what's making more service providers tune into 100G?

In the optical domain, one thing that changed was the reemergence of coherent optics, an advancement that was pushed aside in the 1980s and 1990s in favor of optical amplifiers to overcome signal attenuation in fibers, an issue that can limit the reach of an optical system.

What coherent optics does is reduces the need for amplification and increases the distance. In addition, it reduces chromatic dispersion, meaning a service provider can have wavelengths set closer together with fewer subchannels.

A growing number of vendors, including ADVA Optical (XETRA: ADV.DE), Alcatel-Lucent (NYSE: ALU), Ciena (Nasdaq: CIEN), Cisco (Nasdaq: CSCO), Fujitsu, and Infinera (Nasdaq: INFN) have all stepped up their support for coherent optics in their respective optical product lines.

ADVA, while supporting coherent optics for long haul applications, is also offering a shorter range metro applications (data center connectivity) transponder product that leverages dual binary modulation and non-coherent detection, and relies on four 28 Gbps channels, each inserted into a 50 Ghz sub-channel, to achieve 100G at distances of up to 500 km.

Coupled with the need to deal with the consumer and business user's appetite for bandwidth, service providers are taking charge of the 100G optical opportunity. One of the clear aggressors in this domain is Verizon (NYSE: VZ), which updated seven additional routes to 100G on its IP network this fall in addition to upgrading 10 of its network routes with coherent optical technology.

Outside of Verizon, other notable 100G deployments include a group of savvy Canadian (MTS Allstream and Shaw), European (BT, France Telecom-Orange and P&T Luxembourg), R&E networks (Internet2), and even one city (Washington, D.C.).

But with the desire for higher-bandwidth applications continuing to mount, service providers, researchers and the standards community are already looking for what lies beyond 100G.

While much of the work at this point is still experimental, separate experiments by Caltech and Verizon have illustrated what lies ahead. A group of researchers led by Caltech demonstrated 186 Gbps data transmission during the recent SuperComputing 2011 conference in Seattle, while earlier Verizon and NEC Corp. delivered a paper at this year's NFOEC/OFC conference on how 100 Gbps, 450 Gbps and 1 Tbps network speeds can coexist on one fiber.

Why it's significant: With consumer and business bandwidth needs showing no signs of slowing down, service providers need to prepare their respective long haul, core and even metro networks to support these needs. The advent of breakthroughs like coherent optics and other innovations like Orthogonal Frequency Division Multiplexing (OFDM) that will take optical networks beyond 100G will give service providers the tools they need to make their network transitions work.

Year in review 2011: 100G optical takes flight