Deployment Strategies for 40G/100G: Trade-Offs and Impacts
Read the article
 
 
CWDM/DWDM Reference Poster
View the poster
 

Dense Wavelength-Division Multiplexing


 

Discover additional materials:

DWDM increases the bandwidth of an optical fiber by multiplexing several wavelengths (or colors) onto it. Even though it costs more than CWDM, it is currently the most popular WDM technology because it offers the most capacity. By providing channel spacings of 50 GHz (0.4 nm), 100 GHz (0.8 nm) or 200 GHz (1.6 nm), several hundreds of wavelengths can be placed on a single fiber. Most typical DWDM systems use 40 or 80 channels, although this number can be as high as 160.

The ITU-T G.694.1 frequency grid specifies the wavelengths used in DWDM. They are found in the C-band (1525-1565 nm) and L-band (1565-1620 nm), which is a spectral range that proves very attractive for DWDM. The reason is because it allows amplification with erbium-doped fiber amplifiers (EDFA).

Long-haul, metro and now cellular backhaul networks

DWDM is the most suitable technology for long-haul transmission because of its ability to allow EDFA amplification. This is why it was adopted in these networks a few decades ago. Given the growing need for bandwidth to driven by data-hungry applications (smartphones, video streaming, etc.), DWDM has now found its way into metro networks, and is even being used in some cellular backhaul deployments.

DWDM network testing

DWDM networks must be tested for loss, connector cleanliness, dispersion and spectral quality. EXFO offers all the right tools to ensure smooth DWDM operation, including inspection probes, OTDRs, power meters, dispersion testers and optical spectrum analyzers.

Related Resources

 
Sort by:
123
 

This white paper demonstrates that traditional OSAs, with precise specifications for each application, are perfectly adapted to carry out the typical OSA measurements in the field, and that high-resolution OSAs are not required for field use.

Last updated: 2015-10-30

High-Speed Product Portfolio

Brochures and Catalogs

Discover our future-proof 40G/100G product portfolio featuring comprehensive test solutions covering OTN, Ethernet and SONÈT/SDH technologies. From network construction and fiber characterization to commissioning, turn-up and troubleshooting, our portfolio gives you the tools you to need to accelerate time-to-market, save costs, and deliver high-speed services in the field and the lab.

Order Hard Copy
Last updated: 2015-03-04

This paper explores the trade-offs of greenfield and brownfield nextgenerationarchitectures, the impairments these approaches giverise to, as well as ways to reduce the operational costs that theseimpairments generate for service providers, based on data from theITU-T G. 697 standard®. The topic of proper spectral planning andmanaging capacity will underlay this entire paper.

Last updated: 2014-11-05

When deploying 40G/100G technologies, service providers must choose whether the new wavelengths will be deployed over an existing network and traffic (brownfield deployments) or over unused, new fibers (greenfield deployments). This choice usually depends on the context, type of network (metro, long-haul, etc.), capacity requirements and so forth. But more importantly, each approach has its pros and cons, and specific set of challenges. 

Last updated: 2014-10-07

123