100 GigE in the Long Run

Long haul fiber optic networks, including core networks for regional and national carriers, are headed up in bandwidth capacity as Internet and private networking users keep demanding more and more Gbps. The most recent upgrades have been to 40 Gbps. But XO Communications and Infinera are getting ahead of the curve by demonstrating 100 Gigabit Ethernet on the XO long-haul DWDM network.

The reason for the partnering of the two companies is that there are two pieces to the puzzle. You need a long haul network with the inherent capacity to carry the signals. XO is a leading competitive carrier with that kind of capacity. You also need equipment that can make good use of available network capacity. That's what Infinera specializes in.

Infinera creates a 100 Gbps transport network by concatenating ten 10 Gbps fiber wavelengths. DWDM or Dense Wavelength Division Multiplexing offers up to 160 individual wavelengths, also known as lambdas, on a single optical fiber. When all wavelengths are pressed into service, the total capacity is 1.6 Tbps or Terabits per second of bandwidth. We're not at the point of needing quite this much just yet. But if video streams keep multiplying the way they have been, that type of network capacity is not too far fetched.

Infinera is also providing a service known as bandwidth virtualization. Philosophically similar to server virtualization, this is a technique that decouples bandwidth services from whatever the underlying transport infrastructure happens to be. Bandwidths can be deployed at rates from 1 Gbps to 100 Gbps using protocols such as Ethernet, SONET/SDH, or wavelengths. Without bandwidth virtualization, the network you've installed dictates the type of service available.

All of these capabilities are contained in the Infinera DTN system, a transport chassis containing a band mux module, digital line module, tributary adaptor module and management control module. A full bay provides 800 Gbps of capacity. Infinera and XO Communications are using this equipment to demonstrate long haul 100 GigE service at NXTcomm08 this week. A 100 Gigabit/sec Ethernet signal is injected into the Infinera DTN in Las Vegas, transported to Los Angeles on the XO network, and looped back to Las Vegas where it is recovered and monitored.

Thanks to advances by companies like Infinera and XO Communications, Gigabit Ethernet for business use is no longer something to dream about. It's now readily available in major metropolitan areas with very attractive lease rates. Standard 10 Mbps and Fast 100 Mbps Ethernet is available to many more businesses using fiber optic or Ethernet over Copper last mile connections.