I attended the Next Generation Optical Networking conference held annually in Nice, France this past June. Besides learning that Nice, France is a beautiful city and a taxi strike is really inconvenient when traveling, I learned a thing or two about 200 Gbps DWDM wavelengths!

  • One of which is that nearly every service provider (at least those presenting at the conference) is testing it, trialing it, or deploying it.
  • The second is that even though 200 Gbps wavelengths using 16 QAM modulation is span limited, it can be the perfect solution for a number of service providers; and that a longer span solution may not be immediately needed to drive demand.

This second point partially goes against one of my premises for the adoption of higher speed wavelengths. Historically, at least ONE condition had to be met before demand for a higher speed wavelength entered a growth inflection: It had to be economically better. That is, the price-per-bit-per-kilometer of a 200 Gbps wavelength must be less than that of a 100 Gbps wavelength. However, this condition is not met by 200 Gbps wavelengths, today. Even if a 200 Gbps transponder card is priced the same as a 100 Gbps transponder card, its un-regenerated span length is less than half of that of a 100 Gbps wavelength. This premise of mine is based on historical demand inflection points for the adoption of 10 Gbps, 40 Gbps, and 100 Gbps. Something, I’ve watched for over a decade as an industry analyst.

I still think 200 Gbps demand will truly reach its high point when the technology matures and spans of greater than 1,200 km can be reached. But I now wonder if the demand for 200 Gbps can enter a growth inflection sooner as a result of the growing bandwidth requirements in metro markets.

The best demonstration of this was from a presentation by Takeshi Seki, an Optical Network Technology & Planning Manager at NTT Communications Corporation. He showed a heat map of bandwidth across Japan, and pointed out that the highest bandwidth consumption was in the two metro cities of Tokyo and Osaka, as well as the interconnection between the two cities. Outside of these areas, traffic demand dropped off. This is where NTT would like to use higher wavelength technology at a better price point. This is where 200 Gbps wavelengths fit in for them.

Others mentioned something similar, and as I thought about it, I’m sure other country networks are similar. Especially as content locations de-centralize and get positioned closer to consumers.

Now I get to ponder, whether this will cap the market growth for 100 Gbps DWDM in metro applications…




Posted by Jimmy Yu on July 16, 2015

About Jimmy

Jimmy Yu built our coverage on the Microwave Transmission market, significantly expanded coverage on the Optical Transport market, and is responsible for Storage Systems market research. He has authored several Advanced Research Reports on Mobile Backhaul and is researching Carrier SDN.