A wavelength or lambda is light at a particular frequency or color. This characteristic is generally expressed in terms of wavelength in nanometers rather than frequency in terabits per second. Just as frequencies can be multiplexed to create a broadband wireline service, wavelengths can be multiplexed to offer multiple paths through a single fiber strand.
The multiplexing process at the physical level for fiber optics is called WDM or Wavelength Division Multiplexing. There are two technologies available. CWDM or Coarse Wavelength Division Multiplexing creates anywhere from 2 to 20 independent wavelengths, with 16 being a standard. DWDM or Dense Wavelength Division Multiplexing requires more precise equipment to create from 40 to 128 or more independent wavelengths.
As you can imagine, having dozens of independent wavelengths per fiber optic core and perhaps 100 cores in a cable, the amount of available bandwidth is truly staggering. So much so, that carriers are leasing out entire wavelengths to companies and organizations that need high bandwidth conduits. Wavelength services are similar to point to point T1 lines in that you have exclusive use of the wavelength. While the wavelengths in any particular core may be leased by dozens of different users, any multiplexing on the particular wavelength you are leasing is up to you. It's a private line service, with the line being a particular wavelength of light.
What bandwidths are available on these wavelength services? Commonly available speeds are 2.5 Gbps and 10 Gbps. Other increments of 1 Gbps and 5 Gbps are also increasingly available. Need more than 10 Gbps? It's possible to get as much as 40 Gbps in some areas. Can 100 Gbps be far behind?
Another advantage of wavelength services is that they are not locked into a particular protocol. You can use your wavelengths to transport Fast Ethernet (100 Mbps), Gigabit Ethernet, SONET OC-3, OC-12, OC-48, Fibre Channel, ESCON and Frame Relay.
Who's offering wavelength services suitable for large enterprise and other organizational use? Major competitive carriers such as Level 3, XO Communications and AboveNet have these and other fiber optic bandwidth services available right now. If you have a serious application that needs connectivity at this level, find out what wavelength services are available for your business locations.
