Tag Archives: DWDM MUX/DEMUX

How to Save Cost for 500Gbps Metro Network Over Long Distance?

Increasing bandwidth has always been the most important task of telecom engineers. Through decades of research and engineering effort, 40Gbps and 100Gbps solutions have been used for network applications. But 40G and 100G transceivers can’t support too much long distance (QSFP-40G-ER4 for 40 km, QSFP-100G-LR4 for 10 km). How to extend the 500Gbps link to thousands of kilometers in Metro network within limited budget?

Save Fiber Cost–500Gbps Over Single Fiber Cable

Fiber cable cost takes a certain percentage in the whole network budget. Point to point connection needs many cables, while WDM technology take well care of this issue. In a metro network, usually multiple 10Gbps signals are transmitted by the use of DWDM Mux/Demux over a single fiber cable, which can save lots of money on multiple fiber cables and cable management issues. Then how to save cost to transmit 500Gbps signals over single fiber cable?

It sounds unbelievable. But we have the cost-effective solution. As we know, it will cost too much to replace all the current network system for upgrading to higher data rate. To save cost for increasing bandwidth, some producers add an extra port on DWDM Mux/Demux and that is 1310nm or 1550nm port. This port supports 1310nm or 1550nm transceiver. With such port, you can add 1G/10G/40G/100G to the existing DWDM network. For instance, we use 40-channel C21-C60 dual fiber DWDM Mux/Demux with 1310nm port and 1310nm band port for 1G/10G/40G/100G “grey” light. Plug 10G DWDM SFP+ transceivers into 40 channels, the overload is 400Gbps. Once plugging a 1310 40G QSFP+ LR4/ER4, then the total link reach up to 440G (400G + 40G). If install a 100G QSFP28 LR4 transceiver into 1310 port, the whole transport will be 500Gbps (400G + 100G). See this solution realize the goal of saving cost to run such huge network load over a single fiber.

500g dwdm network

40ch dwdm mux-demux

Extend 500G Transmission Distance

Since 500G signals can be transmitted over a single fiber cable, we have another issue to be solved. 500G transmission distance is needed far more than few kilometers in real life, maybe thousand of kilometers. How to extend the transmission distance?

According to IEEE standard, LR4 and ER4 transceivers can support the reach of 10 km and 40 km in the in ideal conditions, not considering fiber loss or connector loss. To extend 500Gpbs transmission distance, we need SOA (Semiconductor Optical Amplifier) and EDFA (Erbium Doped Fiber Amplifier). Add an SOA to support 40G/100GBASE-LR4 transceiver (over 1310 nm). The SOA is used to amplify incoming (Rx) signal on the receiving side of the link. So that the distances can reach up to 60 km. In 10Gbps DWDM networks, the signal transmission distance can be extended to hundreds of kilometers by the use of and EDFA (Erbium Doped Fiber Amplifier).

500g dwdm network-1

Recommended DWDM Solutions for 500Gbps Metro Network
ID# FS Part Number Description
35887 40MDD-1RU-A1-FSDWDM 40 Ch 1RU Duplex DWDM MUX DEMUX C21 to C60 with 1310nm Port and Monitor Port
14491 DWDM-SFP10G-40 10GBASE 100GHz DWDM SFP+ 40km, LC Duplex Interface, C21 to C60
31533 DWDM-SFP10G-80 10GBASE 100GHz DWDM SFP+ 80km, LC Duplex Interface, C21 to C60
14599 DWDM-XFP10G-40 10GBASE 100GHz DWDM XFP 40km, LC Duplex Interface, C21 to C60
14650 DWDM-XFP10G-80 10GBASE 100GHz DWDM XFP 80km, LC Duplex Interface, C21 to C60
24422 QSFP-LR4-40G 40G QSFP+ LR4 1310nm 10km, LC Duplex Interface
36173 QSFP-ER4-40G 40G QSFP+ ER4 1310nm 40km, LC Duplex Interface
51679 CFP2-LR4-100G 100G CFP2 LR4 1310nm 10km, LC Duplex Interface
35192 FS-SOA-G10 10dB Gain 1310nm Semiconductor Optical Amplifier
36524 FMT26PA-EDFA 16dBm Output C-band 40 Channels 26dB Gain Booster EDFA

Summary

DWDM technology is very necessary to extend Metro Network reach. In this 500Gpbs Metro network, I have introduced very detailed cost-effective solutions. Remember all the indispensable DWDM equipment such as DWDM transceivers, DWDM Mux/Demux, EDFA, etc. For more information, please visit the site about FS.COM Long Haul DWDM Network Solution.

Related articles:

How to Extend 40G Connection up to 80 km?
Economically Increase Network Capacity With CWDM Mux/DeMux

How to Extend 40G Connection up to 80 km?

As 40G connectivity is accelerating, many data centers prepare to migrate from 10G to 40G. But the link distance between 10G and 40G switches is a big challenge. This article can help you extend 40G connection distance.

Current 40G QSFP+ to 4x10G Connection—Max 10 km

As we know, 40GBASE-SR4 QSFP+ is designed for short distance of up to 150m connection. 40GBASE-PLR4 QSFP+ can support long distance link of up to 10 km. Both 40G QSFP+ modules are interfaced with 12-fiber MTP/MPO and can break out into 4x10G connection. To build 10G-40G connection, for instance, using singlemode 8-fiber MTP-LC harness cable to connect 40GBASE-PLR4 QSFP+ and 4x10G SFP+ modules. As the direct connection distance between two 40GBASE-PLR4 QSFP+ optics can reach at most 10km, it’s easy to understand that the connection between 10G and 40G may be shorter. However, we provide a method to extend 40G connection to 80km distance. Continue to read this article and find the answer.

10km max

Equipment for Extending 40G QSFP+ Connection

To extend 40G QSFP+ connection distance, we have to use WDM transponder OEO (Optical-Electrical-Optical) repeater. OEO repeater allows connection between fiber to fiber Ethernet equipment, serving as fiber mode converter, or as fiber repeater for long distance transmission. It can also function as CWDM/DWDM optical wavelength conversion. Now we will use a multi-service transport system, including a hot-swappable plug-in OEO card which only occupies 1 slot. The other space can be left for holding more cards such as DCM, EDFA, OLP. On the left side, there is a card for centralized network management.

WDM transponder oeo

This is a 4-channel multi-rate WDM transponder with an OEO-10G card containing 8 SFP/SFP+ slots and can support up to 11.3G rate. The OEO card can convert 1G~11.3 Gbps Ethernet signals into a corresponding wavelength in CWDM and DWDM network infrastructures. Transmission distance can reach 80 km.

Except WDM transponder OEO repeater, we still need DWDM Mux/Demux and DWDM SFP+ to extend the distance to 80 km. DWDM Mux/Demux is to combine 4x10G signals of different wavelengths on one single fiber so that it’s the best solution to increase network capacity and save cost. Here we use 40-channel C21-C60 dual fiber DWDM Mux/Demux. So we can choose suitable 10G DWDM SFP+ modules 80km transceiver between the wavelengths of C21 and C60.

For your reference, the equipment for 40G connection extension mentioned above are from FS.COM. You can select those of other specifications according to your own needs.

Equipment Details
Fiber Transceiver 40GBASE-PLR4 QSFP+ 1310nm 10km MTP/MPO Transceiver
Generic Compatible 10GBASE-LR SFP+ 1310nm 10km DOM Transceiver
C21-C60 DWDM SFP+ 80km DOM Transceiver
Transponder Repeater 4-channel WDM transponder OEO repeater
DWDM Mux/Demux 40 Channels C21-C60 Dual Fiber DWDM Mux Demux with Monitor Port, 3.0dB Typical IL
Extend 40G QSFP+ Connection to 80 km

Install 40GBASE-PLR4 QSFP+ into QSFP+ port of a switch and 4 10GBASE-LR SFP+ into the Ethernet ports of the WDM transponder OEO repeater. Then plug a singlemode 8-fiber MTP-LC harness cable to connect 40GBASE-PLR4 QSFP+ and 4 SFP+ modules. Because of the OEO repeater function, 4x10G Ethernet signals are converted into corresponding wavelengths in DWDM network infrastructure. Then install 4 x 10G DWDM SFP+ transceivers into other four ports of OEO repeater. Next step is to connect DWDM SFP+ modules on the OEO repeater and DWDM Mux/Demux by using LC duplex patch cables. In this way, 40G QSFP+ distance can be extend up to 80 km.

40G-80km

Conclusion

10 km transmission distance is not the limit of 40G to 4x10G connection. From this article, you can extend 40Q QSFP+ to 80 km by mainly applying WDM transponder OEO repeater, DWDM Mux/Demux and 10G DWDM SFP+. If need to break your network distance limit, please visit our site www.fs.com or contact us via sales@fs.com.

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Economically Increase Network Capacity With CWDM Mux/DeMux
Check out All CWDM Transceiver Modules
User Guide for CWDM MUX/DEMUX

A Wise Decision to Choose DWDM Mux/DeMux

The advent of big data requires for highly efficient and capable data transmission speed. To solve the paradox of increasing bandwidth but spending less, WDM (wavelength division multiplexing) multiplexer/demultiplexer is the perfect choice. This technology can transport extremely large capacity of data traffic in telecom networks. It’s a good way to deal with the bandwidth explosion from the access network.

WDM

WDM stands for wavelength division multiplexing. At the transmitting side, various light waves are multiplexed into one single signal that will be transmitted through an optical fiber. At the receiver end, the light signal is split into different light waves. There are 2 standards of WDM: coarse wavelength division nultiplexing (CWDM) and dense wavelength division multiplexing (DWDM). The main difference is the wavelength steps between the channels. For CWDM this is 20nm (course) and for DWDM this is typically 0.8nm (dense). The following is going to introduce DWDM Mux/Demux.

DWDM Technology

DWDM technology works by combing and transmitting multiple signals simultaneously at different wavelengths over the same fiber. This technology responds to the growing need for efficient and capable data transmission by working with different formats, such as SONET/SDH, while increasing bandwidth. It uses different colors (wavelength) which are combined in a device. The device is called a Mux/Demux, abbreviated from multiplexer/demultiplexer, where the optical signals are multiplexed and de-multiplexed. Usually demultiplexer is often used with multiplexer on the receiving end.

Mux/Demux

Mux selects one of several input signals to send to the output. So multiplexer is also known as a data selector. Mux acts as a multiple-input and single-output switch. It sends optical signals at high speed over a single fiber optic cable. Mux makes it possible for several signals to share one device or resource instead of having one device per input signals. Mux is mainly used to increase the amount of data that can be sent over the network within a certain amount of time and bandwidth.

Demux is exactly in the opposite manner. Demux is a device that has one input and more than one outputs. It’s often used to send one single input signal to one of many devices. The main function of an optical demultiplexer is to receive from a fiber consisting of multiple optical frequencies and separate it into its frequency components, which are coupled in as many individual fibers as there are frequencies.

mux-and-demux

DWDM Mux/Demux modules deliver the benefits of DWDM technology in a fully passive solution. They are designed for long-haul transmission where wavelengths are packed compact together. FS.COM can provide modules for cramming up to 48 wavelengths in 100GHz grid(0.8nm) and 96 wavelengths in 50GHz grid(0.4nm) into a fiber transfer. ITU G.694.1 standard and Telcordia GR1221 are compliant. When applied with Erbium Doped-Fiber Amplifiers (EDFAs), higher speed communications with longer reach (over thousands of kilometers) can be achieved.

Currently the common configuration of DWDM Mux/Demux is from 8 to 96 channels. Maybe in future channels can reach 200 channels or more. DWDM system typically transports channels (wavelengths) in what is known as the conventional band or C band spectrum, with all channels in the 1550nm region. The denser channel spacing requires tighter control of the wavelengths and therefore cooled DWDM optical transceiver modules required, as contrary to CWDM which has broader channel spacing un-cooled optics, such as CWDM SFP, CWDM XFP.

DWDM Mux/Demux offered by FS.COM are available in the form of plastic ABS module cassette, 19” rack mountable box or standard LGX box. Our DWDM Mux/Demux are modular, scalable and are perfectly suited to transport PDH, SDH / SONET, ETHERNET services over DWDM in optical metro edge and access networks. FS.COM highly recommends you our 40-CH DWDM Mux/DeMux. It can be used in fiber transition application as well as data center interconnection for bandwidth expansion. With the extra 1310nm port, it can easily connect to the existing metro network, achieving high-speed service without replacing any infrastructure.

DWDM MUX DEMUX

Conclusion

With DWDM Mux/DeMux, single fibers have been able to transmit data at speeds up to 400Gb/s. To expand the bandwidth of your optical communication networks with lower loss and greater distance capabilities, DWDM Mux/DeMux module is absolutely a wise choice. For other DWDM equipment, please contact via sales@fs.com.

User Guide for CWDM MUX/DEMUX

Is there a way to enhance your network system but also save cost, time and effort? Do you want to give up traditional model of using many fiber cables? The cost-effective way is to use the CWDM MUX/DEMUX (coarse wavelength division multiplexing multiplexer/demultiplexer). If you are the first time to use it, you are lucky to read the following content.

18-ch-cwdm-muxdemux

CWDM Mux/Demux Introduction

First you need to know what CWDM is. CWDM is a technology which multiplexes multiple optical signals on a single fiber by using different wavelengths of the laser light to carry different signals. CWDM MUX/DEMUX applies this principle. A CWDM MUX/DEMUX can maximize capacity and increase bandwidth over a single or dual fiber cable. It mixes the signals in different wavelengths onto a single fiber and splits it again into the original signals at the end of a link. This kind of device is used to reduce the number of required fiber cables and get other independent data links. CWDM MUX/DEMUX modules are wide from 2 channels to 18 channels in the form of 1RU 19’’ rack chassis. The following will take 9 channels 1290-1610nm single fiber CWDM Mux/Demux as an example. It’s a half 19’’/1RU module for LC/UPC connection.

Features are as follows:
  • Support up to 9 data streams
  • Wavelength range: 1260~1620 nm
  • Low insertion loss, half 19’’/1RU module low profile modular design
  • Passive, no electric power required
  • Simplex LC/UPC for line port
  • Duplex LC/UPC for CWDM channel port, easily support duplex patch cables between the transceiver and passive unit
  • Operating temperature: 0~70℃
  • Storage temperature: -40~85℃
9cwdm-2743-1u-lc-sfb
Preparation for Installation

To connect the CWDM Mux/Demux, you need two strands of 9/125μm single-mode fiber cables. Supportable transceivers cover the wavelengths of 1290 nm, 1370 nm, 1410 nm, 1450 nm, 1490 nm, 1530 nm, 1570 nm 1610 nm. And this device is used together with 9 CWDM-2759-LC-LGX-SFB.

front-channel

To ensure a reliable and safe long-term operation, please note the points below:

  • Only use in dry and indoor environments.
  • Do not locate CWDM Mux/Demux in an enclosed space without airflow since the box will generate heat.
  • Do not place a power supplies directly on top of a unit.
  • Do not obstruct a unit’s ventilation existing holes.
System Installation Procedures

1.To install CWDM MUX/DEMUX system, switch off all devices.
2.Install CWDM transceivers. Remember each channel has a unique transceiver with a certain wavelength. So each transceiver must be plugged into the appropriate channel and must not be used more than once in the system. Devices pairs must carry transceivers with the same wavelength.
3.Connect CWDM MUX/DEMUX units with matching cables (single-mode fiber). Before connecting cable, you should first inspect if the connectors are lean. Never forget cleaning work is an important factor to achieve a better network performance. The guidelines:

  • Keep connectors covered when not in use to prevent damage.
  • Usually inspect fiber ends for signs of damage.
  • Always clean and inspect fiber connectors before make a connection.

4. Power up the system.

Troubleshooting

When you connect the system, but you find there is not data link. Then you need to do:

  • 1. Check the attached devices by directly connecting CWDM MUX/DEMUX units using a short fiber cable.
  • 2. Check the fiber cables and fiber connectors.
  • 3. Check that each wavelength doesn’t occur more than once at the CWDM MUX/DEMUX units.
  • 4. Check if the transceivers are inserted into the matching port at the CWDM MUX/DEMUX units.
Conclusion

CWDM MUX/DEMUX is a cost-effective solution for expanding bandwidth capacity for short link communication. Besides saving costs, CWDM lasers consume less power and take up less space. FS.COM offers both CWDM MUX/DEMUX and DWDM MUX/DEMUX with high quality. If you are the first time to use these devices, keep in mind the above notes.