Tag Archives: reliable 4 channel CWDM Mux

Dual-Fiber or Single-Fiber CWDM Mux Demux for Higher Capacity Need?

What would you do if your network capacity can not meet your requirement? Will you put more fibers or update your system? In fact, these two methods are not very recommendable. Why? As your fiber cabling infrastructure is limited for adding fibers and high cost is required for upgrading system, these two methods are unworkable or too expensive. Under this condition, using a pair of CWDM Mux Demux to build a CWDM system with higher capacity is highly recommended. The CWDM Mux Demux is regarded as a key component for a CWDM system, as shown below. It can be simply divided into two types, dual-fiber and single-fiber CWDM Mux Demux. To meet the higher capacity need of your system, this post will mainly introduce the basic knowledge of the dual-fiber and single-fiber CWDM Mux Demux and guide you find a suitable fiber optic Mux Demux for building your CWDM system.

CWDM Mux Demux for Connecting Cisco Nexus 9396PX and FS S5850-3252Q

Dual-Fiber CWDM Mux Demux

Dual-Fiber CWDM Mux Demux is a passive device multiplexing and demultiplexing the wavelengths for expanding network capacity, which must work in pairs for bidirectional transmission over dual fiber. It enables up to 18 channels for transmitting and receiving 18 kinds of signals, with the wavelengths from 1270 nm to 1610 nm. The CWDM transceiver inserted into the fiber optic Mux port should have the same wavelength as that of Mux port to finish the signal transmission. For instance, the two reliable 4 channel CWDM Mux Demux showed below use four wavelengths, 1510 nm, 1530 nm, 1550 nm and 1570 nm, their corresponding CWDM transceivers also features the same wavelengths.

Dual-Fiber CWDM Mux Demux

When the connection above works, the left 4 channel dual-fiber CWDM Mux Demux uses 1510 nm, 1530 nm, 1550 nm and 1570 nm for transmitting 4 kinds of signals through the first fiber, while the right 4 channel dual-fiber CWDM Mux Demux features 1510 nm, 1530 nm, 1550 nm and 1570 nm for receiving the signals. On the other hand, the transmission from the right to left use the same wavelengths to carry another 4 signals through the second fiber, finally achieving the bidirectional signal transmission.

Single-Fiber CWDM Mux Demux

Single-fiber CWDM Mux Demux should be also used in pairs. One multiplexes the several signals, transmits them through a single fiber together, while another one at the opposite side of the fiber demultiplexes the integrated signals. Considering that the single-fiber CWDM Mux Demux transmitting and receiving the integrated signals through the same fiber, the wavelengths for RX and TX of the same port on the Single-fiber CWDM Mux Demux should be different. Hence, if the 4 channel single-fiber CWDM Mux Demux is used for CWDM system, 8 wavelengths are required, the twice time as that of the dual-fiber one.

Single-Fiber CWDM Mux Demux

The working principle of single-fiber CWDM Mux Demux is more complicated, compared to the dual-fiber one. As shown in the figure above, the transmission from the left to right uses 1470 nm, 1510 nm, 1550 nm and 1590 nm to multiplex the signals, transmit them through the single fiber, and using the same four wavelengths to demultiplex the signals, while the opposite transmission carries signals with 1490 nm, 1530 nm, 1570 nm and 1610 nm over the same fiber. As for the wavelength of the transceiver, it should use the same wavelength as TX of the port on the CWDM Mux Demux. For example, when the port of a single-fiber CWDM Mux Demux has 1470 nm for TX and 1490 nm for RX, then a 1470nm CWDM transceiver should be inserted.

Dual-Fiber vs. Single-Fiber CWDM Mux Demux

We always consider whether an item is worth buying according to its performance and cost. In view of the performance, the single-fiber CWDM Mux Demux can carry signals through only one fiber supporting fast speed transmission and saving the fiber resource, while the dual-fiber one requires two fibers for transmission with a higher reliability. Besides, using single-fiber CWDM Mux Demux can be easier to install. In view of the cost, the single-fiber CWDM Mux Demux is much more expensive than the dual-fiber. And the simplex fiber cable also costs higher than duplex fiber cable. Thereby, the whole cost for building single-fiber CWDM system must be much more higher. Like the two sides of the same coin, both the dual-fiber and single-fiber CWDM Mux Demux have their own advantages and disadvantages. Which one you should choose just depends on your system needs and your budget for building the CWDM system.

How to Deploy a Single-Fiber CWDM Network?

Generally, CWDM network designed for expanding the network capacity can be basically divided into two types, dual-fiber and single-fiber CWDM network, according to the optical fiber transmission line. For the dual-fiber CWDM network, its working principle is easy to acquire, which uses the same wavelength for transmitting and receiving each pair of dual-way signals over the duplex fiber cable. However, for the single-fiber CWDM network, the working principle is highly complex that specially works with different wavelengths for transmitting and receiving each pair of dual-way signals over only one fiber. To better understand the single-fiber CWDM network, here will mainly illustrate how does a single-fiber CWDM network work and introduce the components and installation steps for fast deploying a single-fiber CWDM network.

Introduction of Single-Fiber CWDM Network

Single-fiber CWDM network is a kind of WDM network, designed for greatly expanding the network capacity by combining and transmitting several pairs of dual-way signals with different wavelengths over a single fiber, instead of putting more fibers for lager dual-way data transmission need. When the single-fiber CWDM network runs, there are two single-fiber CWDM Mux Demux using two different wavelengths for each pair of dual-way transmission. In details, if the single-fiber CWDM Mux Demux has four channels for dual-way data transmission, then eight different wavelengths divided into four pairs are required for the four channels, as shown in the figure below. To make a comparison, a 4 channel dual-fiber CWDM Mux Demux only needs four different wavelengths for the dual-way transmission.

 4 Channel CWDM Network

From the figure above, we can learn that a 4 channel CWDM network needs two reliable 4 channel CWDM Mux Demux connected by a single fiber and four pairs of CWDM transceivers with eight different wavelengths connected to the CWDM Mux Demux, achieving the dual-way transmission. Obviously, each port of the two CWDM Mux Demux for the same channel has the complete reversed TX and RX. Just taking the first channel as example, the first port of the CWDM Mux Demux on the left side uses 1470nm for TX and 1490nm for RX, while the first port on the right side uses 1490nm for TX and 1470nm for RX, reversely. Hence, each pair of dual-way signals with two different wavelengths will be smoothly transmitted and received. To better understand how does the single fiber CWDM network work, the following table also lists the four pairs of wavelengths for the TX and RX ports of the two CWDM Mux Demux, which are also totally reversed.

TX and RX for Single-Fiber CWDM Mux Demux

Basic Components for a Single-Fiber CWDM Network

When deploy the single-fiber CWDM network, we should prepare two single-fiber CWDM Mux Demux, two switches, a rack-mount chassis, several pairs of CWDM transceivers and singlemode simplex patch cables that are the basic and essential components for a single-fiber CWDM network. The two switches separately act as the Local unit and Remote unit for the CWDM network, while the CWDM Mux Demux is the main unit of the network that should be fixed and held on the rack-mount chassis and then connected to the switch. To finish the connection between the CWDM Mux Demux and switch, we should insert the CWDM transceivers into the ports of CWDM Mux Demux and use the singlemode simplex patch cables to connect CWDM transceivers with the switch.

Basic Components for a Single-Fiber CWDM Network

Steps for Single-Fiber CWDM Network Deployment

To fast deploy a single-fiber CWDM network, here offers the step by step installation procedure.

Step A: Install the rack-mount chassis in a standard 19-inch cabinet or rack.

Step B: Align the single-fiber CWDM Mux Demux with the chassis shelf, slightly push it to the shelf cavity. And tighten the captive screws once the CWDM Mux Demux is totally inserted.

Step C: Plug the CWDM transceivers into the switch. And also, connect these CWDM transceivers to the corresponding ports on CWDM Mux Demux according to the wavelengths of the TX and RX, with the use of singlemode simplex patch cable.

Step D: Utilize the singlemode simplex patch cable to connect the two CWDM Mux Demux and test the performance of the whole single-fiber CWDM network.

Installation Steps for Single-Fiber CWDM Network

Conclusion

Single-fiber CWDM network is a cost-effective and easy-to-deploy solution that can not only take full use of the available fiber bandwidth in your network but also greatly expand your network capacity. If you are hesitating over upgrading your system for bigger capacity, buy CWDM multi-channel Mux/Demux, CWDM transceivers and other basic components to deploy the single-fiber CWDM network would be a better choice for you.