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 system

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.

Embedded CWDM Solution for Fiber Channel SAN Extension

CWDM, as an established optical transport technology, is universally employed in optical network for transmission distance extension and fiber exhaust reduction. This technology has evolved for years and now is available for Fiber Channel applications with the rate up to 4.25Gb/s. Moreover, when compared with traditional transmission approach via multiple fibers, embedded CWDM technology also makes economic sense while used in 4G Fiber Channels, and that’s what we are going to address in this article.

Fiber Channel Overview

The 4G Fiber Channel effectively improves storage area networks (SANs) performance by doubling speed and offering backward compatibility with 2G and 1G systems. With the proliferation of bandwidth-extensive applications, fiber capacity is on the edge of exhaustion. However, the demand for extremely high-capacity data transmissions began to soar. In this case, it is critical for IT technicians to enhance Fiber Channel SAN capacity without increasing costs.

Economical Fiber Channel Solution: Embedded CWDM Technology

CWDM technology expands fiber capacity by multiplexing optical light signals of different wavelength on a single optical fiber. In a CWDM network, components like CWDM Mux/Demux and CWDM transceivers are indispensable. With CWDM, IP data (Gigabit Ethernet or 10G Ethernet) and storage data (4G/2G/1G Fiber Channel) can be transported over a single fiber infrastructure, eliminating the need for complex protocol conversion.

Until now, standalone CWDM solutions are the commonly used methods to transport LAN connections and SAN connections simultaneously between main and recovery sites. Despite that it generates high equipment cost and reduces system reliability. In this case, embedded CWDM emerges as an ideal alternative for use in Fiber Channel applications. Embedded CWDM integrates CWDM optics (like CWDM SFP transceivers) directly into the Fiber Channel switch or Ethernet router, offering better reliability and simplicity. Thus instead of laying more fibers and equipment, users can extend system capacity only by adding new CWDM SFPs, which greatly reduces human labor and overall expenditure.

embedded CWDM solution with CWDM SFPs

Embedded CWDM for Distance Extension in 4G Fiber Channel

While used for SAN distance extension, CWDM functions to reduce the amount of required WAN fibers. Here we take the example of a SAN extension between a primary site and secondary site. With solution A, the implementation requires several WAN fibers to get the capacity required.

multiple fiber in SAN

As for solution B, CWDM is adopted to multiplex several signals onto a single fiber pair. CWDM SFPs are directly plugged into the ports from the Fiber Channel switch to generate signals of specific CWDM wavelength. The CWDM Mux combines wavelengths onto a fiber pair, while the CWDM Demux splits these wavelengths into several fiber on the receiver site. Thus the number of required WAN fibers is reduced by the number of wavelengths used.

embedded CWDM in SAN extension

Benefits of Embedded CWDM Solution

Embedded CWDM system is easier to operate, which requires no additional network management or training. It introduces more reliability, flexibility and simplicity due to fewer components involved in the system. And its advantages become more evident when it comes to cost: Embedded CWDM solution simply offers lower investment expenditure and operation cost, since it removes the need for adding new fibers and equipment, which can be cost-prohibitive. Even that CWDM SFPs and CWDM Mux/Demux should be involved in CWDM system, the overall cost is just a fraction of multiple fiber transmission.

Conclusion

CWDM solution allows IT managers to achieve network capacity expansion in a more cost-effective, simplified and flexible way. Besides, it also provides enhanced performance and reliability for current need and future growth. For more CWDM solutions and information, visit www.fs.com or contact us via sales@fs.com.

Pre-terminated Copper Cables: Interconnect & Cross Connect Solution

Copper cables are regarded as the optimal solution for data center, which provides significant benefits in the respect of capital expenditures, operating expenditures, performance, and reliability. Pre-terminated copper cable assemblies, emerging as a new copper cabling option for network architectures such as MoR (Middle of Row) or EoR (End of Row), are recommended for interconnect and cross-connect applications in data center.

What Is Pre-terminated Copper Cable Assemblies ?

Pre-terminated copper cable assemblies consisting of pre-terminated copper trunks and copper patch cords (usually terminated with RJ45 connector), are ideal for data center applications which  require high-efficient deployment. Being factory pre-terminated and strictly tested, the pre-terminated copper cable assemblies simplify network installation and maintenance, saving users much time and energy. Moreover, they offer more flexibility to be disassembled and repurposed to accommodate MACs (moves, adds and changes), facilitating management when rapid network growth and migration required.

data-center-copper-cabling

Commonly used in point-to-point connections in data centers, pre-terminated copper trunk cables enable reliable connectivity between server and switch cabinets. While copper patch cords are used to connect panels to switches and servers. Moreover, intelligent patch cords are available to monitor port status.

Tips: various termination types are available for the pre-terminated trunks, such as jack-to-jack, jack-to-plug, plug-to-plug, cassette-to-cassette, and so on. So, your choice should base on the layout of the data center or telecommunications room, and the design philosophy employed.

How to Use Pre-terminated Copper Cable Assemblies?

Pre-terminated copper cable assemblies can be used in data center for backbone or intra-rack cable connectivity. This section illustrates the interconnect and cross-connect connectivity using pre-terminated copper cables in universal data center cabling applications.

Interconnect

For general data center cabling, copper trunk cables are used to make a permanent link between patch panels on each ends—one end is in a switch/network cabinet, and the other end is in a server/storage cabinet. And patch cords are usually used to interconnect the active equipment such as switches, servers, etc.

interconnect

Cross Connect

In cross-connect cabling configuration, an individual patching area (often including two or more adjacent patch panels) is usually added between the switch/network cabinet and server/storage cabinet. Thus, two copper trunk cables are used as two permanent links between them. One runs from the switch/network cabinet panel to cross-connect panel, and the other one runs from cross connect panel to the panel in the server/storage cabinet. Copper patch cords are used to interconnect the active equipment and patch panels at the switch/network cabinet, cross-connect cabinet, and server/storage cabinet.

cross-connect

FS.COM Pre-terminated Copper Cable Assemblies Solution

FS.COM offers a wide range of configurable pre-terminated copper cable assemblies and patch panels to meet the demand for faster deployment and guaranteed performance in data center copper cabling, help saving time and money.

Pre-terminated Copper Cable Assemblies Pre-terminated Copper Trunk Cable
Copper Patch Cords Cat5e Patch Cord
Cat6 Patch Cord
Ca6a Patch Cord
Cat7 Patch Cord
Modular Patch Panel Cat5e Patch Panels
Cat6 Patch Panels
Other Accessories Cat5e Connector/Plugs
Cat6 Connector/Plugs
Cat7 Keystone Jacks & Plugs
Conclusion

Pre-terminated copper cable assemblies offer an ideal solution for data center interconnection and cross connect applications. All the pre-terminated copper cables, patch panels and related accessories presented in the above chart are available in FS.COM. For more details, please visit www.fs.com for contact us directly via sales@fs.com.

How to Realize 16 Channels Transmission in DWDM Network?

DWDM MUX/DEMUX plays a critical in WDM network building. 16 channels transmission is very common in DWDM networks. How to realize it in a simple way? This article intends to introduce two solutions to achieve 16 channels with different types of components. Which one is more cost-effective and competitive? The comparison between the them also will be explored. Hope it will help you when choosing fiber mux for your DWDM networks.

wdm network

Solutions to Achieve 16 Channels Transmission in DWDM Network

In order to illustrate the solution more clearly, I take two types of DWDM MUX/DEMUX as an example. One is the traditional 16 channels dual fiber DWDM MUX/DEMUX. Another is two FMU 8 channels dual fiber DWDM MUX/DEMUX. The latter has an expansion port.

Solution One: Using Traditional 16 Channels DWDM MUX/DEMUX

The 16 channel DWDM MUX/DEMUX is a passive optical multiplexer designed for metro access applications. It’s built fiber mux and demux in one unit and can multiplex 16 channels on a fiber pair. In addition, this type of fiber mux also can be added some functional ports like expansion port, monitor port and 1310nm port, which make it possible to increase network capacity easily. The following is a simple graph showing the 16 channels transmission with this traditional DWDM MUX/DEMUX.

16 channels dwdm mux demux

Solution Two: Using Two FMU 8 Channels DWDM MUX/DEMUX Modules

The FMU 8 channels DWDM MUX/DEMUX provide 8 bidirectional channels on a dual strand of fiber. Usually they are used together. Unlike the 16 channels DWDM MUX/DEMUX, this FMU 8 channels one has a more compact size, for it only occupies half space in a 1U rack. Put two FMU 8 channels DWDM MUX/DEMUX modules into one 1U two-slot rack mount chassis. two 8 channels DWDM MUX/DEMUX with different wavelengths are connected through the expansion port to realize 16 channels transmission in a DWDM network. Here is a graph showing how to achieve 16 channels DWDM transmission with these two 8m channels fiber muxes. As shown in the figure, two 8 channels DWDM MUX/DEMUX with different wavelengths are connected through the expansion port to realize 16 channels transmission in a DWDM network.

8 channels

16CH DWDM MUX and Two FMU 8CH DWDM MUX: What’s the Difference When Deployed?

From the content above, we can see both solutions can realize the 16 channels transmission in a DWDM network. Then, are there differences between them? Or which is more competitive? Here is a simple analysis of the two solutions.

fiber mux

Firstly, comparing the two graphs above, the FMU 8 channels DWDM MUX/DEMUX are connected together by an expansion port, that’s why it can deliver 16 channels services like the traditional one. Except for connecting 8 channels DWDM MUX/DEMUX, the FMU fiber mux with expansion port also can be combined with other channels fiber mux like 2 channels, 4 channels or other channels, which offer more flexibility for optical network deployment and upgrade. And you can add DWDM into CWDM networks at some specific wavelengths with FS.COM FMU fiber mux.

Secondly, DWDM MUX/DEMUX price is always an important point that many network operators pay attention to. Therefore, when buying a fiber mux, the cost is a critical point to consider. If you search on Google, you will find the lowest price is $1100 in FS.COM. And the cost of using two 8 channels MUX/DEMUX is the same as the deployment of one 16 channels MUX/DEMUX. However, compared with the 16 channels DWDM MUX/DEMUX, the FMU 8 channels fiber mux provides a competitive solution for small networks which needn’t to buy a full-channel fiber mux that supports all 16 channels or more channels.

Conclusion

From the comparison above, the FMU 8 channels DWDM MUX/DEMUX is more flexible and cost-effective when deployed in WDM networks. How to choose is based on the requirements of your networks. FS.COM supplies two different types of these WDM MUX/DEMUX. Here is a simple datasheet of them. If you have more requirements for additional wavelengths, welcome to visit www.fs.com for more detailed information.

Application
ID
Description
16 channels
16 ch. DWDM Mux Demux, C27-C42, , IL <4.6dB, duplex LC/UPC
8 channels
8 ch. Dual Fiber DWDM Mux Demux, C53-C60, with expansion port, IL <4.6dB, LC/UPC

LC-LC Patch Cable in Data Center

LC-LC patch cable has already become the main force of high density cabling network infrastructure. To future increase the profits of LC-LC fiber patch cable, manufactures has invented LC-LC patch cables of different features to meet various requirements in data center and increase the network performance.

What Kind of Fiber Patch Cable Is Required in Data Center?

Data center is a place of thousands fiber links. The selection of fiber patch cables will directly affect the network performance. More and more data centers choose to select fiber patch cable of high performance. Generally, insertion loss and return loss of connectors terminated on patch cable and light loss of optical fiber used for fiber patch cable are three most basic factors for fiber patch cable selection. To satisfy the increasing demands for higher density and easier management in data center, the optimization of fiber patch cable has never stopped. The following introduces several popular LC-LC fiber patch cables which represent the trends of fiber patch cable that data center is asking for.

LC-LC fiber patch cable

Low Insertion Loss and Bend Loss LC-LC Patch Cable

When a length of fiber patch cable is connected in network, optical light loss occurs at the optical fiber and the connectors terminated on it. There are different optical light losses, among which insertion loss at the connectors and bend loss in fiber optic cables are the two most commonly light losses that technicians are trying to overcome. Manufactures provides LC-LC fiber patch cables which can minimize these losses to the most.

Insertion loss refers to the fiber optic light loss caused when a fiber optic component insert into another one to form the fiber optic link. To provide low insertion loss patch cable, LC connectors terminated on the patch cable has been optimized. Standard LC-LC patch cable usually has an insertion loss less than 0.3 dB. However, for upgraded LC-LC patch cable, the insertion loss is usually lower than 0.2 dB. To decrease the bend loss, a type of bend insensitive fiber (BIF) has been used in fiber patch cable. With optimized LC connectors and bend insensitive fiber, LC-LC fiber patch cable could provide lower light loss during network transmission.

uniboot LC cable

High Density LC-LC Patch Cable

LC connector was invented for higher cabling density. standard duplex LC-LC fiber patch cable can provide much higher cabling density than other duplex fiber patch cables. To further increase cabling density in data center, the connectors and cable diameter of LC-LC patch cable are becoming smaller. Uniboot LC-LC patch cable is a typical example. This kind of fiber patch cable designed the two fibers of the duplex patch cable into a single cable. In adding the two connectors terminated at each end of the duplex patch cable share the same boot. With less using cable counts, uniboot patch cable can provide higher cabling density and better cooling environment in data center.

Polarity Switchable LC-LC Patch Cable

The development of patch cable won’t stop at low loss and high density. Making fiber patch cable easier-to-use is also important. Polarity of fiber patch cable matters a lot during installation of fiber patch cable, especially for duplex fiber patch cable and MTP patch cable. It is common to change the polarity of a duplex patch cable during deployment. Technicians might need tools to change the polarity of patch cable. However, a polarity switchable LC-LC patch cable can make things much easier. Without any tools you can polarity reversal could be really easy. The following picture shows the polarity reversal of a special designed LC-LC patch cable.

polarity switchable LC patch cable

Conclusion

LC-LC patch cable has been designed into many different types. A high performance fiber patch cable should not only provide low insertion loss and bend loss, but also higher cabling density and easy-to-use features. This is also the trend of data center development.