The thing about fiber optic transmission is that it offers almost limitless bandwidth. That’s a foreign concept to anyone who’s been tied to copper wireline services. It’s also an odd notion for those who pick a fiber optic service level and sign a contract for it. If you order OC3 SONET service, what you get is a line that runs at 155.52 Mbps with a payload of 148.608 Mbps. You don’t have to fill the pipe continuously, but the capacity is there all the time. If you need more bandwidth, you only recourse is to add an additional service or upgrade to something like OC12 or Gigabit Ethernet.What you are using with fiber optic services is not the entire bandwidth of the fiber. In fact, you may be totally unaware that your signals are multiplexed with lots of others all traveling on the same fiber strand. If there is only one laser beam with a single color or wavelength shining through that fiber, it likely has a capacity of at least 10 Gbps. Chances are, though, that there are many different color beams all riding simultaneously down the fiber. They don’t interfere because they are different colors of light, called Lambdas, all in the infrared region of the spectrum. Each Lambda or wavelength has a carrying capacity as high as 10 Gbps. You can think of these as equivalent to individual high capacity lines. If the fiber optic strand were made of copper, each wavelength would be a separate pair of wires.
What if you could lease a wavelength instead of a copper wireline or a fixed bandwidth service on a fiber optic cable? The wavelength doesn’t care what modulation or data pattern you use. It’s just a pure light beam of one wavelength. There’s no fancy footwork required to convert between one protocol and another just to be compatible with what’s running on the line. That opens some interesting possibilities. You could use your leased wavelength to carry Gigabit Ethernet or Fast Ethernet, SONET OC3, OC12 or OC48, Fibre Channel, or ESCON.
Need to transport a variety of high bandwidth protocols? OK. Just lease multiple wavelengths and give each protocol its own Lambda. The won’t interfere. In fact, they won’t even known the other wavelengths exist.
This type of network transport is no longer a pipe dream. All you need to do is lease WDM Wavelength Services from a fiber optic network carrier such as AboveNet. What AboveNet has done is install a base of dark fiber in many metropolitan areas. It’s called dark because it hasn’t already be put into service with a particular fiber optic service in mind. It’s like a blank canvas ready to become any work of art. AboveNet “lights” the fiber as needed using WDM equipment to create their wavelength services.
WDM stands for Wavelength Division Multiplexing. It’s the technology that creates multiple wavelengths on a single fiber strand. This is a standardized process that ensures there is enough separation between the wavelengths that they won’t interfere and that different brands of networking equipment will work together. There are two flavors of WDM: CWDM or Coarse Wavelength Division Multiplexing and DWDM or Dense Wavelength Division Multiplexing. The difference is that DWDM squeezes more wavelengths, up to 160, onto a given fiber but at a higher cost than CWDM.
Is this affordable? AboveNet says that their CWDM service becomes competitive at the OC-3 service bit-rate. If you can use more bandwidth than that, you’ll save money with CWDM. Typical applications include connecting corporate headquarters with branch offices and data centers, or connecting multiple hospitals and medical centers for exchange of medical images and other health service records.
Has your business or organization become limited by the network services available? Perhaps it’s time to move up to wavelength services. Find out by getting prices and availability of fiber optic wavelength services for your locations. Complementary consulting by bandwidth experts is also available for serious applications.
Note: Image of light spectrum from prisms courtesy of Marcellus Wallace on Wikimedia Commons.
