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Migration From CWDM to DWDM

Migration From CWDM to DWDM

CWDM (Coarse Wavelength Division Multiplexing) and DWDM (Dense Wavelength Division Multiplexing) have their own advantages and their combination can greatly enhance transmission performance while reducing OPEX and CAPEX spending. Hybrid CWDM/DWDM solution is a flexible and scalable solution which offers many benefits to network carriers, especially in network expansion and upgrade. Today, I will introduce a simple, plug-and-play option for creating hybrid systems of DWDM channels interleaved with existing CWDM channel plans.

Understanding the Principle of Hybrid CWDM/DWDM

The difference between CWDM and DWDM lies in the channel spacing between neighbored wavelengths, for CWDM 20 nm and for DWDM 0.8/0.4 nm (using 100 GHz/50 GHz grid). A typical CWDM mux has a window of +-6.5nm per channel. Thereby several DWDM channels can be transmitted simultaneously in only one CWDM channel. Typically, 1530nm or 1550nm CWDM channels are commonly used for achieving hybrid CWDM/DWDM.

1530 nm C52-C61
1550 nm C27-C42


Deploy Hybrid CWDM/DWDM

Deployment of hybrid CWDM/DWDM is very easy by using a simple, plug-and-play solution offered by FS.COM—FMU 2-slot 1U Rack Mount with matching CWDM & DWDM plug-in modules. As shown in the following picture:


The CWDM plug-in module is a high-band 8 channels module of 1470nm-1610nm wavelengths, with expansion port. And the DWDM module can be 8 channels C54-C61 or 8 channels C34 -C41. In addition, by using EXP port, the further expansion is available.


Hybrid CWDM/DWDM solution offers many advantages for users, especially in cost savings and flexibility of network expansion. The 2-slot plug-and-play solution is a very cost-effective to achieve hybrid CWDM/DWDM in the limited 1U rack. In addition, it’s very flexible and scalable that users can easily deploy the CWDM, DWDM or hybrid CWDM/DWDM. If you are interested in the FMU 2-slot plug-and-play solution and want to know more details, please contact or visit here.

Related article: How much do you know about the ports on WDM MUX/DEMUX?

How Much Do You Know About the Ports on WDM Mux/DeMux?

How Much Do You Know About the Ports on WDM Mux/DeMux?

WDM (Wavelength Division Multiplexing) Mux/DeMux (Multiplexer/De-Multiplexer) is one of the most important components of WDM systems. You can easily find that there are many ports on the Mux/DeMux with 1RU housing. So, how much do you know about them? And why we need them on the equipment?


Common Port

The connection point of a WDM product where combined channels appear. For a MUX product, combined channels are transmitted from the common port. For a DEMUX, the combined channels are received at the common port.

Express or Upgrade Port

For CWDM products, there will normally be either an upgrade or an express port, but not both. The upgrade or express port on a CWDM Mux or DeMux is used to add, drop, or pass through additional channels which enables the cascading of two CWDM Mux/DeMux modules, doubling the channel capacity on the common fiber link.

For DWDM products, the purpose of an upgrade port is to be able to add, drop, or pass through C-band DWDM channels not already in use, namely only channels that reside in the band 1530 – 1565 nm. If the DWDM product also has an express port, then that port is normally used for additional channels residing outside the C-band, such as most of the CWDM channels.

1310nm Port

The 1310nm port is a wide band optic port added to other specific CWDM wavelengths in a module. For example if an 8 channel CWDM is called out it may use wavelengths 1470 nm to 1610 nm and request the 1310nm port. The 1310nm port is used in some legacy networks and sometimes as a return path. If an existing legacy network is using 1310nm port and they have exhausted all fibers and are looking for ways to increase their network capacity they can add in other CWDM wavelengths on to the same fiber while still allowing the use of the 1310nm port. Meanwhile, it can carry LR optics, LX optics etc.

1550nm Port

Similar to 1310nm port, allows a legacy 1550nm signal to pass and can carry ER optics, ZR optics, LX optics, ZX optics etc.

Monitor Port

This port is used to monitor or test the power signal coming out of a Muxed CWDM or before it gets demuxed from the signal coming through the fiber network usually at a 5% or less power level. Generally, it can be connected with measurement or monitoring equipment, such as power meters or network analyzers. Network administrators will use this to test of monitor if a signal has failed or changed without having to interrupt the existing network.

WDM-equipmentAs is mentioned above, the commonly used ports on WDM Mux/DeMux are with different applications. Each device has common port, but might not has express or upgrade port, 1310nm port, 1550nm port or monitor port. These ports are belong to special service and can be custom to equip with the device according to your requirement. If you have any demand on CWDM or DWDM Mux/DeMux, as well as OADM, I highly recommended you to visit as they can support various of WDM equipment with competitive price and ready stock advantages.

Fiberstore- Best choice for your 4 channels Simplex CWDM Mux & Demux LGX Module!

Fiberstore- Best choice for your 4 channels Simplex CWDM Mux & Demux LGX Module!

Are you trying to find info on 4 channels Simplex BIDI Transmission CWDM Mux & Demux LGX Module? And are you still not making your mind to pick up one because of the limited cost? Or do you want to customize an unique module for special need? Fiberstore provides complete information about this goods right this moment. 4 channels LGX Module Simplex BIDI Transmission CWDM Mux & Demux (type A/type B), our best-selling product at this time, is keeping an enough store and good price as well as offering the customized service. With highly performance and reasonable price, we will be proud to announce that such product is absolutely a good device for your network solution!

Fiberstore continually strives to provide the most current products for our customers. Thanks to the research and testing performed by our experienced engineers, we have opportunity to offer the most advanced technology available. Expecially the CWDM Mux & Demux module, as a flagship product line of all the optical products, its quality and technology are both the best and advanced. In addition to ensure the quality, Fiberstore also has a very reasonable price and good service all around the world.

Why can Fiberstore’s CWDM Mux & Demux module be such excellent in both quality and price?
Fiberstore’s Research & Development and Engineering teams provide strong innovative capability, who have core technical knowledge ranging from optoelectronic device, optical subassembly, and module design, to product and manufacturing process development expertise. On the other hand, advantages of the unique conditions of abundant and cheaper resouse of the components in our factory in China, makes it possible to be saled to the end users with such reasonable price.(Figure 1.)
test department

Figure 1. Research & Development and Engineering teams in Fiberstore

Fiberstore’s customized 4 channels Simplex BIDI Transmission CWDM Mux & Demux LGX Module
In order to satisfy the demands of customers, Fiberstore add a new design in the modules. No matter what kind of connectors (such as FC, ST, SC, LC, etc.) are all available, and we can also mix connectors on one device. Like the following customized 4 channels LGX Module Simplex BIDI Transmission CWDM Mux & Demux (type Atype B). We can see Figure 2.,this customized product is designed in mix connectors on the device-SC/APC & LC/PC so that it can save the cost and easy to used.
4 channels Simplex BIDI Transmission CWDM Mux & Demux LGX Module

Figure 2. customized 4 channels Simplex BIDI Transmission CWDM Mux & Demux LGX Module

Item Details

  • 4 channels CWDM mux and demux in one LGX
  • Com port is simplex
  • Connector: Com&1310:SC/APC Other: LC/PC
  • LGX Cassette
  • It is equipped with configuration ports like Monitor, Express port according to customer choice (see options)
  • Front panel is equipped with adapters according to customer choice (see options)
  • Passive, no electric power required. (MTBF ca. 500 years)
  • Low insertion loss
  • Simple to install, requires no configuration or maintenance
  • ISO 9001 manufacturing facility
  • It should be used with 4 channels, Type A, LGX Module, Simplex BIDI Transmission, CWDM Mux & Demux in pair

To ensure the quality of each product, there is a Test data report for every product when produced(Figure 3.). In addition, original packages, fast worldwide shipping and one year warrenty are including in our services.

Figure 3. Test Data Report of CWDM Mux & Demux

Don’t hesitate anymore! Come to Fiberstore, you can directly make oder on one of our products or customize an unique device for your special use. Know more, click here!

Fiber Saving-Wavelength Division Multiplexing (WDM) Technology !

Fiber Saving-Wavelength Division Multiplexing (WDM) Technology !

Big Data,Internet,video and cloud computing are driving relentless bandwidth growth and increasing demands on service provider,enterprise,and government networks.The appearance of a new technology which is high-performance applications,scale more easily,operate more efficiently and reduce costs seems to be the trend of the times.So,now what?
Most are turning to Wavelength Division Multiplexing (WDM) technology in order to increase capacity around the fiber links which are already in place!

What’s Wavelength Division Multiplexing (WDM) technology?
WDM is really a technology which multiplexes multiple optical signals on one fiber by utilizing different wavelengths,or colors,of laser light to carry the various signals. Through the use of bidirectional communications on the single fiber,network managers can realize a multiplication effect within their available fiber`s capacity.There is a simple example concerning the WDM technology.begin to see the Figure 1.If each color of light carries a data rate of 10 Gbit/s,then,combining 4 colors of light in to the same fiber increases the total data rate four fold to 40 Gbit/s.
basic wdm technology diagram In addition,there’s two critical factors inside a WDM system which are the optical wavelength multiplexer (MUX), and also the de-multiplexer (DEMUX). We are able to begin to see the Figure 2 below,an optical prism represents a handy method to understand a MUX/DEMUX function. Whenever a multi-color light beam goes through an optical prism, because of its unique material property and geometry, light of various colors will exit at different angles and become, in WDM terminology, optical de-multiplexing. Conversely, if light of multi-colors are sent through the prism at different predesignated angles, they’ll exit the prism in the same angle like a single light beam becoming, in WDM terminology, optical multiplexing.
ingress vs egress
CWDM MUX/DEMUX (Coarse Wavelength Division Multiplexer/Demultiplexer)
CWDM MUX/DEMUX is a flexible and low-cost solution that allows the development of existing fiber capacity. Along with highly reliable passive optics certified for environmentally hardened applications,the CWDM MUX/DEMUX solution lets operators take advantage of available fiber bandwidth in local loop and enterprise architectures.
Advantages of CWDM:
Passive equipment that utilizes no electrical energy
Much lower cost per channel than DWDM
Scalability to develop the fiber capacity when needed
with little or no increased cost
Protocol transparent
Simplicity of use

Fiberstore CWDM MUX/DEMUX Products
Fiberstore supplies a complete portfolio of CWDM MUX/DEMUX to match all applications for example:Gigabit & 10G Ethernet,SDH/SONET,ATM,ESCON,Fibre Channel,FTTx and CATV.And that we provide optional port configurations for example:Express Port,Monitor Port,1310nm passband port and 1550nm port of these multiplexers based on customer choice.

 CWDM mux


DWDM MUX/DEMUX(Dense Wavelength Division Multiplexer/Demultiplexer)
DWDM MUX/DEMUX may be the technology preferred by transporting extremely large amounts of information traffic over metro or long distances in telecom networks. Optical networking and especially using DWDM technology has proven to be the optimal method of combining cost efficient transport with advanced functionality, which could deal with the bandwidth explosion from the access network.
Advantages of DWDM:
Up to 32 channels can be achieved passively
Up to 160 channels by having an active solution
Active solutions involve optical amplifiers
to achieve longer distances

Fiberstore DWDM MUX/DEMUX Products
DWDM MUX/DEMUX modules are members of a number of high end products according to silica-on-silicon planar technology. The AWG chips Fiberstore employed for DWDM MUX/DEMUX are focused on Long-Haul, Metro and access applications, where outstanding optical performance and occasional cost are paramount.
CWDM and DWDM technology comparison
To see the Figure 3, there is a comparison between CWDM and DWDM technology. A CWDM MUX/DEMUX deals with small amounts of wavelengths,typically eight, but with large spans between wavelengths(spaced typically at around 20nm). A DWDM MUX/DEMUX deals with narrower wavelength spans (no more than 0.8nm,0.4nm or perhaps 0.2nm), and may accommodate 40,80,or even 160 wavelengths.


Read more about the WDM system,please click here!

Using CWDM Technology To Construct Cost-Effective Fiber Networks

Using CWDM Technology To Construct Cost-Effective Fiber Networks

The utilization of fiber optic cables for communication has opened up gates for communication multiplexing technologies that increase the capabilities at minimum costs. Coarse wavelength division multiplexing (CWDM) modulates different wavelength laser beams with multiple signals. Essentially, what this means is maximized utilization of a single fiber optic to deliver and get a large number of signals, minimizing costs for telecom companies. Companies simply employ the right optical amplifiers, multiplexers and demultiplexers to boost capacity from the fiber optic using CWDM technology.

In CWDM technology, it comes with an increase in channel space. This means requirement of less sophisticated and less costly transceiver devices. Operating in the same window of 1550 nm and making use of OH-free silica fibers, maximum efficiencies are achieved in channels 31, 49, 51, 53, 55, 57, 59 and 61. The channels are spaced 20 nm apart. DWDM spaces them 0.4 nm apart. Less precision optics minimizing cost, uncooled lasers with lower maintenance requirements can therefore be used in CWDM devices, operating in the region of 1470, 1490, 1510, 1530, 1550, 1570, 1590 and 1660nm. 18 different channels can be used with wavelengths as much as 1270 nm. For instance, a 8 channel CWDM includes 8 different CWDM channels. In addition to being economical, power consumption for laser devices used in CWDM technology is also far less.

CWDM signals cannot be transmitted long term but are ideal for applications inside a range of 60 km for example in a city as well as for cable tv networks allowing upstream and downstream signals. CWDM product is usually considered a low-cost alternative which is now widely used to replace the DWDM system. Due to the benefit of CWDM technology uses low cost lasers that don’t need cooling and low-cost passive filter. Moreover, if using CWDM technology, we can use low-cost and smaller transceivers such as CWDM 10Gig SFP+. However, because of relatively large CWDM channel spacing, so the system will reduce the number of available wavelengths, this also limits the system’s transmission capacity.

Related technologies are dense wavelength division multiplexing (DWDM) and conventional WDM. Conventional WDM use the 3rd transmission window with a wavelength of 1550nm, accommodating as much as 8 channels. DWDM is identical however with a higher density channel. Systems could use 40 channels, each at 100 GHz spacing or 80 channels spaced 50 GHz apart. A technology, the ultra dense WDM is capable of doing working in a spacing of just 12.5 GHz, allowing more channels. However, DWDM and WDM are much more expensive in contrast to CWDM.

A quantity of manufacturers offer all related CWDM multiplexer, demultiplexer and optical amplifier. Networking solution providers would be the right individuals to seek guidance for use of CWDM, DWDM or WDM technology. They perform entire installation and commissioning from the right, integrated devices for error-free high speed, high data transmissions over fiber optic cables. Cost and gratifaction optimized CWDM solutions with built-in expansion capabilities can be found from reliable and trusted online network solution companies. Choose the best one with years of experience and technological expertise to provide the best CWDM solution and use the CWDM technology to construct your cost-effective fiber optic networks.