On a recent trip from Munich to Meiningen, I set myself a challenge of counting the number of local exchanges and street cabinets that came into view. In my defense, my iPod was flat and there was little to listen to on the radio. Needless to say, this task proved a little more difficult than I expected. In fact, I lost count somewhere around 100.

Still, I was amazed at the number of facilities that service providers needed to maintain. The cost when considered on a national scale is enormous. This was part of the reason I was travelling to Meiningen. I was visiting our Next-Generation Access (NGA) Solution center, designed to show the impact of eliminating active equipment between the Central Office (CO) and Customer Premise (CP) to some of our customers.

In this scenario, residential, business and wholesale access/backhaul demands are served over one infrastructure built on Wavelength Division Multiplexing over Passive Optical Network (WDM-PON) technology.

In my opinion, a NGA network built on WDM-PON has the ability to overcome many of today's networking obstacles, including, unsymmetrical data transport (uplink vs. downlink), security constraints and limited scalability. As an example, when downloading videos, music or other large data files, you are heavily depending on the uplink of your source and with peer-to-peer networks growing it is mainly the uplink that is limiting your download performance

WDM-PON combines the PON infrastructure (efficient usage of the fiber) with logical point-to-point Ethernet connectivity. End-users are separated by individual wavelengths providing secure links compared to the shared bandwidth approach of GPON, EPON or XGPON. The splitting ratio of WDM-PON technology is flexible, e.g., 1:8, 1:16, 1:40, 1:80, and the wavelength can also vary, 1Gbit/s, 4Gbit/s, 10Gbit/s, with the ability to coexist on the same infrastructure. The data transport distance (~60km) is another advantage of WDM-PON technology towards more energy-efficient access networks.

Clearly, adoption of this technology will at first be limited to backhaul and second-mile aggregation. Migration will be gradual, as links become bandwidth constrained. But eventually, bandwidth providers will increasingly leverage the more substantial benefits of WDM-PON, as the migration of their legacy networks accelerates. Further technology evolutions, such as tuneable SFPs, will help WDM-PON to finally break through in the last mile.

If you have any thoughts on NGA approaches or would like to suggest other items that I can count on my journeys, I'd be interested to hear from you.

Read more about WDM-PON here.