Boosting Network Capacity With CWDM

Boosting Network Capacity With CWDM

CWDM and DWDM are both wavelength division multiplexing (WDM) technologies that enable multiple signals on different wavelengths to be transmitted over a single fiber. CWDM systems support up to 18 channels, while DWDM supports up to 80 simultaneous wavelengths.

CWDM optical transport solutions are available as active or passive systems. In a passive system, the transceiver resides inside a device, such as a data switch or router.


CWDM is an excellent cost-effective solution to meet the bandwidth requirements of today’s converged Ethernet services. Unlike DWDM, which requires new lasers and transponders, CWDM uses existing fiber infrastructure and can increase network capacity at a low incremental cost.

The key to reducing the cost of CWDM is to optimize the configuration of the transport platform, and to use less expensive filters, multiplexers/demultiplexers and dispersion compensation modules. This approach reduces the number of components required, the size and weight of the transport device, the need for alignment, and the amount of power used.

As a result, CWDM technology is becoming more and more popular in the market. This is mainly due to its lower costs, as well as the benefits of using it.

One of the main benefits is that CWDM systems are able to connect different types of transport devices, including fast Ethernet switches, ATM switches, gigabit routers and so on. This makes CWDM a great choice for a wide range of applications and networks, from enterprise LANs and SANs to central office to customer premise interconnection.

Another benefit is that CWDM is more flexible than DWDM, enabling service providers to easily upgrade their networks to support higher speeds with no change in the underlying infrastructure. This means that they can upgrade their 10G CWDM system to 40G or 100G without having to replace or modify the existing fiber infrastructure.

CWDM is also more compatible with passive optical networks (PON) because it can multiple different wavelengths in a single fiber cable, which eliminates the need for higher-cost active electronics. This saves money and helps service providers make better use of their existing fiber infrastructure.


Wavelength division multiplexing (WDM) technology combines signals from several sources onto one fiber optic cable by using different wavelengths of light. This method allows companies to upgrade their network capacity without installing new fiber, leasing additional fibers or tearing out existing cables.

CWDM systems can carry eight wavelengths on a single fiber. This makes them suitable for short-range communications, such as metropolitan short distance transmission or enterprise networks. CWDM can also be used to separate a high-speed signal into slower components that are easier to transmit, which can lower network operating costs and increase revenue.

However, CWDM is not as flexible as DWDM, which can be used to carry up to 48 wavelength channels on a single fiber. This is because CWDM wavelengths are spaced far apart, whereas DWDM wavelengths are packed more densely, meaning they can be amplified to travel farther.

Another key difference between CWDM and DWDM is the bandwidth capacity of the system. CWDM is designed to provide low-cost, lower capacity (sub-10G), and shorter distance applications where cost is important. CWDM can only transmit up to 80km, but DWDM can be amplified for longer distances and can carry more than 18 ITU channels for greater capacity.

In some cases, CWDM is not enough to meet bandwidth needs, and it becomes necessary to deploy DWDM. PacketLight’s DWDM over CWDM solution lets a company add up to 28 more DWDM wavelengths on top of an existing CWDM system, enabling higher bandwidth and higher speeds. It also provides a cost-effective alternative to adding additional fiber or tearing out existing cables. Moreover, it can enable companies to expand their addressable market by offering lower-priced high-speed services.


CWDM (Coarse Wavelength Division Multiplexing) can boost bandwidth in the access network by breaking signals into smaller chunks that cwdm can be transmitted more economically. This technology is ideal for carriers looking to address traffic growth without replacing existing equipment with higher bit rate transmission equipment and without installing new fibers.

Typically deployed on fiber runs up to 80km or less, CWDM is less expensive than DWDM and can also be used for lower capacity applications (sub-10G) and shorter distances because it uses 20-nm channel spacing between 1470 and 1610 nm. This spacing allows the use of moderately priced optics, and a single CWDM transceiver can carry eight optical channels with a 20-nm interval between each channel.

One of the most important advances that have boosted CWDM performance is cwdm the development of zero-water peak fiber (ZWPF) to eliminate excess water-peak attenuation in the 1350 to 1450 nm range. This technology has also improved CWDM’s ability to scale up to 16 wavelengths, but this range can be limited in some applications because of the physical limitations of fiber optic cables.

Another key advantage of CWDM is its ability to support a wide range of network topologies, including point-to-point, ring and mesh. Using these topologies enables the creation of self-healing networks that will automatically recover from network problems such as node failure and link breakage, ensuring data integrity and security.

CWDM can also be applied to enterprise and central office networks that require transport of several services simultaneously over a single fiber. The ability to use CWDM in this way can help service providers overcome fiber shortage challenges. It is a cost-effective solution to transport several services simultaneously, and it can even help increase additional capacity on routes that have fiber exhaustion.


CWDM is a cost-effective technology for carriers to use in the access, metro and regional networks. It can be used to increase capacity on routes with fiber exhaustion, as well as to transport several services simultaneously without the need to add new fiber.

Compared to DWDM, CWDM systems offer lower power dissipation and smaller size. In addition, they are easy to deploy and operate.

This is why many operators prefer CWDM over DWDM. In fact, more than 60 percent of CommScope’s customers select CWDM over DWDM.

Another advantage of CWDM is that it can be used to extend the reach of a fiber switch and network interface device, or a WAN, across multiple sites. This is particularly beneficial for broadband internet service providers, who have extensive networks that need to be upgraded without the expense of constructing new cable infrastructure.

In addition, CWDM can be used to expand the capacity of existing fiber optic networks in areas that are subject to relatively moderate traffic growth. This allows a carrier to increase the capacity of its network by four times, reducing deployment costs and improving scalability.

Finally, CWDM can be used to transport data at rates of up to 4.25Gbps or higher, depending on the wavelengths that are mapped into the CWDM spectrum. This is important because many carriers do not need to transport data at the full 100Gbps speed.

CWDM is currently being developed into specialized applications and will continue to evolve as a more advanced technology. Combination transport and optical routers or switches are being developed, and add-on CWDM cards are being included in more transport devices as low cost options. Moreover, the increasing demand for CWDM will drive suppliers to decrease costs and increase capacity.


CWDM is a technology that allows for multiplexed fiber optic transmission, providing an effective method to increase the capacity of a network. Compared to dense wavelength division multiplexing (DWDM), CWDM offers higher performance at a lower cost. It is often a preferred solution for metropolitan area networks because of its ease of deployment and low initial costs.

One of the major advantages of CWDM over traditional WDM technologies is its wide bandwidth. It can support high data rates of 3.125 Gbps, and it allows for up to 18 different wavelengths to be transported simultaneously.

Another advantage of CWDM is its ability to expand capacity without needing to replace existing fiber infrastructure. The standard CWDM system can be expanded by inserting additional DWDM wavelengths into the same four CWDM channels. This increases the network’s capacity by up to 28 times, depending on the DWDM over CWDM solution used.

Another important advantage of CWDM is its simplicity. It is an extremely easy technology to configure, allowing users to optimize and tailor it to their specific needs. This makes it an ideal technology for a wide range of applications. The programmable nature of the technology also enables more flexible network scaling. This is an especially useful capability in a multi-layered environment that includes access, backhaul, and core network layers.