Loss of Optical Link

For fiber-based cabling, data transmission is based on the light as the transmission medium. We know that in the transmission process, the loss of light power is inevitable. When connecting components, there will be insertion loss; when optical signals are transmitted over fiber optic cables, there will be attenuation. In addition, the material of optical components and the operation during the cabling have an influence on the amount of loss, which will determine the level of network performance. Therefore, it is necessary to reduce the loss of optical link to a minimum. This article aims to talk about loss of optical link and give some suggestions about loss control.

loss of optical link

Insertion Loss

A complete optical link is finished by the connectivity between different fiber optical components, and no matter what kind of cabling system you are going to deploy, insertion loss is inevitable Take fiber optic connector for example, there is no perfect loss-less connector. It is important to note that even the highest quality connectors will also have insertion loss because of the alignment and the cleanliness. Structured with MT ferrule, MTP connector still has insertion loss which is rated at 0.35 dB maximum. It is impossible to ensure that fiber optic connector does not get dirty. However, dirt and dust can completely obscure the light wavelength and create huge losses.


When light travels through the core of fiber optic cable, the strength of it surely becomes lower. Naturally, the signal strength becomes weaker. This loss of light power is generally called attenuation and it locates on two aspects: internal reasons and external causes, which are also known as intrinsic fiber core attenuation and extrinsic fiber attenuation. Internal reasons of fiber optic loss are caused by the fiber optic cable itself, which is also known as intrinsic attenuation. Basically, there are two main causes of intrinsic attenuation: light absorption and scattering. As for extrinsic fiber attenuation, it is usually caused by improper handling of fiber optic cable. And there are two main types of extrinsic fiber attenuation: bend loss and splicing loss. Besides, fiber optic splicing can also result in extrinsic fiber attenuation.

Loss Control

For the reduction of insertion loss, it is necessary to use fiber optical components of high quality, such as for high-density cabling, MTP fiber connector is preferred.

For the purpose of reducing the intrinsic fiber core attenuation, it is necessary to select the proper fiber optics and suitable optical components for the applications, such as for short distance MTP connectivity, MPO to LC breakout cable utilizes multimode fiber OM3 or OM4; for long distance optical link, single-mode fiber is better than multimode fiber.

For reduction of extrinsic fiber attenuation, it would be better to handle the fiber optic cable properly and splice it with cautious.


Since efficient transmission of light at the operational wavelengths is the primary function of fiber optics needed for a range of applications, the loss of optical link and the potential for its minimization are of great importance in the efficient and economic use of fiber optics. It is essential to take the loss into consideration and reduce the loss to a minimum as much as possible during the cabling process. FS.COM provides high quality fiber optical components with low loss and ensure the high performance of your network, such as MPO fanout cable, MPO patch panel, MTP cassette and so on. If your want to know more details about them, you can visit our site.

Applications of Serial Transmission and Parallel Transmission in Network

In the age of the Internet, we are not unfamiliar with data communication, which refers to the process of transferring data signals between two or more devices. Basically, there are two methods used to transmit data signals: serial transmission and parallel transmission. To put it simply, serial transmission sends data bits one after another over a single channel, while parallel transmission sends multiple data bits at the same time over multiple channels. Both of them are commonly used in network applications and this article will focus on applications of serial transmission and parallel transmission in network.

serial transmission and parallel transmission

Application of Serial Transmission

As in serial transmission, bits are sent sequentially on the same channel (wire), one bit at a time, the cost for wires is low but the speed of transmission is slow. In 10G network, serial transmission is usually utilized. For example, a duplex LC fiber that consists of one fiber for transmitting 10G data signals and one fiber for receiving 10G data signals is typically used to completer the data link. In high-density network applications, it is easy to find LC duplex patch cables deployed to connect different network devices.

serial transmission for 10G network

Application of Parallel Transmission

In parallel transmission, multiple bits (usually 8 bits or a byte/character) are sent on different channels (wires, channels) simultaneously over the same cable. Compared with serial transmission, parallel transmission has a faster bit rate, and the higher cost since multiple wires cost more than one single wire. Parallel transmission is usually used in 40G and 100G network because it can transfer more data signals and achieve higher speeds. For example, MTP trunk cable, terminated with MTP/MPO fiber connector on each end, can be used to achieve the connectivity. In 40G networking applications, a 12-fiber MTP fiber connector is used: 10G is sent along each channel or fiber strand in a transmit and receive direction, and 8 of the 12 fibers are used to provide 40G parallel transmission; in 100G network applications, a 24-fiber MTP fiber connector is used: 10G is sent along each channel or fiber strand in a transmit and receive direction, and 20 of the 24 fibers are used to provide 100G parallel transmission.

parallel transmission for 40G network

Note: Parallel transmission can also be applied to 25G duplex fiber pairs to reach even higher speeds or reduce the number of fibers required at a given speed. For instance, a 100G channel would require four 25G duplex fiber pairs instead of ten 10G duplex fiber pairs.


In network applications, serial transmission is often used in 10G connectivity, while for 40G and 100G connectivity, parallel transmission is preferred. Hope you could acquire some useful information from the article, and have a better understanding of these two data transmission methods. In addition, you can find fiber optic cables mentioned above in FS.COM. Some other fiber optics are also available here, such as 24-fiber MPO MTP loopback, MTP to LC breakout cable, MPO fiber patch panel and so on. If you want to know more details, please visit our site.

Focus on MTP-link

Characterized by providing ideal plug-and-play solutions for structure cabling, pre-terminated cabling system has gained great popularity among data center manager in recent years, and it is considered as the norm for data center network deployment. In this cabling system, optical link is accomplished by pre-terminated cabling assemblies, such as MTP/MPO trunk cable, MTP/MPO to LC breakout cable, MTP/MPO cassette and MTP/MPO fiber optic patch panel. It not difficult to find that all these MTP/MPO fiber optic cable assemblies are based on the structure of MTP/MPO connector. And two types of MTP/MPO connectors—12 fiber MTP connector and 24 fiber MTP connector are commonly used for 40G and 100G transmission. This article will focus on MTP-link and share share some opinions about MTP-link performance with you.

12-fiber MTP connector vs. 24-fiber MTP connector

About Space Utilization

High-density cabling makes the available space in data centers always precious. MTP/MPO fiber optic cable assemblies used in MTP-link that contributes to promoting space utilization are reputably appraised by data center managers. With massive cables being adopted in the data centers to carry out data transmission, MTP-link offers cabling solutions with much higher density and flexibility for data center upgrades.

About Insertion Loss

As well know that insertion loss is inevitable during the cabling. Generally, lower overall optical loss allows more margin for the network to operate, or in the case for some users, offers the option of more connections for patching locations. Therefore, components characterized by low insertion loss will be preferred. For both 12-fiber and 24-fiber MTP/MPO connector performance, the industry standard product rating is 0.5 dB maximum. And using low-loss ferrules, both 12 fiber MPO connector and 24 fiber MPO connector can be rated at 0.35 dB maximum. What’s more, there is no need to worry about higher fiber count will lead to higher insertion loss, because when using proper polishing techniques, 24-fiber MPO/MTP terminations can meet the same performance levels as 12-fiber MPO/MTP assemblies.

About Fiber Utilization

Both 12-fiber MPO cable and 24-fiber MPO cable can be used in 100G applications. When used in 4x25G solutions, 4 fibers of 12-fiber MPO cable will remain unused. As for 24-fiber MPO cable, it can be converted into three 8-fiber 100G channels that run over one cable, with all 24 fibers used to support data transmission. Maybe you feel confused about this, let me take an example. If you need to support twelve 100G channels with the 4x25G standard, by using 12-fiber MPO cable, you will need to install 12 connectors, or 144 fibers total, with 33% of the fiber wasted; while by using 24-fiber MPO cable supporting the same 12 channels, only 4 cables would be required, using 96 fibers total, at 100% fiber utilization.

About Network Performance

It is self-evident that MTP-link offers consistent high levels of network performance for improved network integrity, because the assemblies are factory terminated and the transmission testing is performed by the manufacturer before shipment. This will reduce the likelihood of many problems that may occur with field terminations. Also, testing and troubleshooting time can be greatly saved.


By using MTP components, MTP-link can provide fast installation, high density and high performance cabling for data centers. As 40G and 100G Ethernet is now a trend and hotspot for data center cabling system, MTP-link is a great option for data center managers and the network deployment will benefit a lot from this cabling solution. I hope after reading this article, you can have an in-depth understanding of MTP-link.

How Much Do You Know About Fiber Loopback Cable?

With the widespread adoption of 40G and 100G Ethernet network, cabling system in data centers becomes more and more complicated. Choosing a suitable cabling solution is important, but ensuring the normal operation of optical components is the basic requirement. Therefore, it is necessary to carry out fiber optic testing. On the market, there is an useful tool that can provide cost-effective solution for fiber optic testing application—fiber loopback cable. Have you ever used it? How much do you know about it? This article will guide you to know more about fiber loopbackc able.

Overview of Fiber Loopback Cable

Fiber loopback cable is terminated with two connectors on each end of the cable, forming a loop. From the figure below, we can see that there is a black enclosure outside the optical cable. This improved structure is aimed to protect the cable. In addition, this design makes the fiber loopback cable more compact in size and stronger in use. Fiber loopback cable is used to provide a medium of return patch for an optical signal, especially for fiber optic testing applications and network restorations. It can determine where the fault might lie. Similar as fiber optic patch cord, fiber loopback cable can be classified according to fiber type used and fiber optic connector type. So we can find single-mode fiber loopback cable and multimode fiber loopback cable, as well as LC fiber loopback cable, SC fiber loopback cable and MTP/MPO fiber loopback cable on the market.

fiber loopback cable

Application of Fiber Loopback Cable

Fiber loopback cable is often used to check whether fiber optic transceiver operates normally. As we all know, fiber optic transceiver has two ports, a transmitter port and a receiver port. During the testing process, the fiber loopback cable directly routes the laser signal from the transmitter port to the receiver port. Then we can compare the transmitted pattern with the received pattern to make sure the transceiver is identical and has no errors. Take MPO loopback cables for example, they are mainly used for testing parallel optics, such as 40G and 100G transceivers. In addition, the MPO fiber loopback assembly cable is available in 8 fibers, 12 fibers and 24 fibers, which can be applied according to different requirements of testing applications. To have a better understanding of fiber loopback cable’s working way, here is a figure of fiber loopback cable used for testing application for you.

application of fiber loopback cable


Fiber loopback cable is designed for equipment testing, self-testing, engineering, network diagnostics and measurement applications. It plays an important role in troubleshooting in laboratories and manufacturing environments. Besides, it provides a cost-effective way to test the transmission capability and receiver sensitivity of optical network equipment. When choosing a suitable type of fiber loopback cable, we should take the connector type, polish type, and cable type into consideration.

Comparison Between Base-8 Connectivity and Base-12 Connectivity

As 10G network no longer satisfies the increasing demand for high speed data transmission, many data center managers turn to 40G network. Base-2 connectivity, based on increments of two fibers, is a common type of fiber optical link in 10G network. However, this kind of connectivity is not suitable for 40G network which needs high-density cabling. For 40G network cabling, there are two popular solutions—Base-8 connectivity and Base-12 connectivity. How much do you know about these two cabling solutions? Is there any difference between them? After reading this article, you will find the answer.

Base-12 Connectivity

In Base-12 system, Base-12 connectivity makes use of fiber optical links based on increments of 12 fibers. And 12-fiber or 24-fiber MTP/MPO optical connector assemblies are usually used to accomplish the links, such as 12-fiber or 24-fiber MTP trunk cable. Here is a figure of 24-fiber trunk cable used in Base-12 system for you.

Base-12 system using a 24-fiber trunk cable

Base-8 Connectivity

The Base-8 system still uses the MTP/MPO fiber connector, but the links are built in increments of 8 fibers (as shown in the following figure). Thus 8-fiber trunk cable, 16-fiber trunk cable and 24-fiber trunk cable can be easily found in Base-8 system. Here is a figure of 24-fiber trunk cable used in Base-8 system for you.

Base-8 system using a 24-fiber trunk cable

Comparison Between Base-8 Connectivity and Base-12 Connectivity

Since the number twelve is obviously larger than the number eight, Base-12 connectivity does provide the benefit of connector with higher fiber density compared to Base-8, and thus a larger number of fibers can be installed more quickly when using Base-12 connectivity. However, as 8-fiber transceivers are utilized in most deployments of 40G network, the benefit of matching the fiber count in the MTP backbone connectivity with the fiber count of the transceiver tends to outweigh the density benefit of Base-12 connectivity. In addition, in Base-12 connectivity, four fibers for transmit and four fibers for receive, leaving four fibers unused per connection. This will lead to a significant and costly loss in fiber network utilization. But Base-8 connectivity can be a more cost-effective option for end-to-end MPO to MPO channels and architectures. In fact, Base-8 connectivity is not an universal solution and Base-12 connectivity in some cases may still be more cost-effective. The following part describes the relative benefits when comparing Base-8 versus Base-12 connectivity for a data center deployment.

Benefits of Base-8 Connectivity
  • Optimized for both 2-fiber and 8-fiber transceiver technologies.
  • Enables 100% fiber utilization for 8-fiber transceiver systems without the additional cost and insertion loss of Base-12 to Base-8 conversion devices.
  • Cable harnesses can easily route to all common port counts on switch line cards.
  • Only requires unpinned MTP patch cords for any connections within the link.
  • Most flexible solution for 40G, 100G and 400G transmission networks.
Benefits of Base-12 Connectivity
  • Higher fiber per connector density than Base-8 connectivity.
  • Compatible with the large installed base of existing Base-12 MTP deployments.
  • Where proprietary vendor specific 40G duplex 2-fiber transceiver technologies are deployed, existing Base-12 data center infrastructures offer higher fiber density per connector (Note: the vendor specific technologies are incompatible with each other, and with parallel optics,which may add a level of management complexity in a multi-vendor environment.)

Base-12 connectivity has dominated the 40G network market for years, while the Base-8 connectivity is an additional option to ensure that data centers have the most cost-effective, future-proof network available. And both of them have their own benefits. As for which one to choose, it depends on the requirements of the network deployment. I hope this article can help you have a better understanding of this two cabling solutions.

Three Components Used for Modular Patching Solutions

In the age of the Internet, data communication industry is moving forward at a rapid speed. The size of data centers becomes bigger and the cabling system becomes more complicated. To satisfy high speed data transmission, high-density cabling is easy to be found in data centers. For data center managers, they not only have to think about the right connections between devices, but also have to take cable management into consideration. If the cables are not managed well at the beginning, cable management will be a nightmare at last. Therefore, it is essential to quickly and effectively manage your data center cabling at the first step. But is there any component can function like that? This article is going to introduce three fiber optic components to you—fiber adapter panel, MTP cassette and fiber enclosure.

Fiber Adapter Panel

Preloaded with fiber adapters, the fiber adapter panel is designed to assure flexibility and ease of network deployment and facilitate structured infrastructure. It is commonly used in high-density network applications for cross connections in main distribution, horizontal distribution, and equipment distribution areas. In addition, fiber adapter panel ensures efficient use of space, quick deployment and the highest reliability for the lowest installed cost, which in turn provides a high return on investment. The commonly used fiber adapter panels are LC fiber adapter panels, SC fiber adapter panels and MTP fiber adapter panels. Here is a picture for you, and from MTP MTP adapter, we can figure out it is MTP adapter panel.

MTP adapter panel

MTP Cassette

MTP cassette produced by many MPO MTP cassette manufacturers is usually fitted with 12 fibers or 24 fibers. Structured with LC or SC adapters on the front side of the cassette and MTP adapters at the rear of the cassette, MTP cassette provides secure transition between MTP and LC or SC discrete connectors. Therefore, it is commonly used to interconnect MTP backbones with LC or SC patching. The main advantage of MTP cassette is that it allows for rapid deployment of high density data center infrastructure as well as improved troubleshooting and reconfiguration during moves, adds and changes. You can have a better understanding of the inner structure of MTP cassette.

MTP cassette

Fiber Enclosure

Fiber enclosure can provide easy-to-manage cabling environments and strong protection for fiber optic cables. Besides, it can largely increase the working efficiency and decrease the costs for labor and time.There are two widely used designs of fiber enclosure in general: wall mount fiber enclosure and rack mount fiber enclosure. Here I take FS.COM fiber enclosures (FHD-1UFCE, FHD-2UFCE, FHD-4UFCE) for example, these three types of FHD fiber enclosures are with the size of 1RU, 2RU and 4RU respectively, which you can learn about from the figure below. Made of black powder coated SPCC rugged heavy-duty steel, the FHD fiber enclosures are designed with push/pull out functions, and have flexible mounting options, which are suitable for 10G/40G/100G cabling deployment.

FHD fiber enclosure


After getting a general understanding of fiber adapter panel, MTP cassette and FHD fiber enclosure, let’s come to how to use them in your network deployment. Usually, we have two modular patching solutions: fiber adapter panel with FHD fiber enclosure and MTP cassette with FHD fiber enclosure. When holding fiber adapter panels, FHD fiber enclosure can also hold fiber slack management spools to help manage the cables or optical splice trays to help store the spliced fiber pigtails. For example, besides housing the exact same number of fiber adapter panels, the FHD-1UFCE fiber enclosure can also hold two fiber slack management spools or four optical splice trays; the FHD-2UFCE fiber enclosure can hold two fiber slack management spools or eight optical splice trays; the FHD-4UFCE fiber enclosure can hold two fiber slack management spools or twelve optical splice trays. While when holding MTP cassettes, the number of MTP cassette increases with the expansion of the capacity of the FHD fiber enclosure. For example, the FHD-1UFCE fiber enclosure can hold up to four MTP cassettes; the FHD-2UFCE fiber enclosure eight MTP cassettes; the FHD-4UFCE fiber enclosure twelve MTP cassettes. However, if using FHD fiber enclosure with MTP cassettes, fiber slack management spools or optical splice trays cannot be installed inside the enclosure. As for which solution to choose, it all depends on your specific requirements of network deployment.


We know that how to quickly and effectively manage your data center cabling in the beginning is particularly important. Fiber adapter panel, MTP cassette and fiber enclosure can provide modular patching solutions for great capacity cabling management. And I hope this article is helpful for you.

Know More About Pre-terminated Trunk Cable Assemblies

In high-density data center environments, the ability to install cabling systems rapidly can save both time and money. Pre-terminated trunk cable assemblies provide ideal plug-and-play solutions for structure cabling—pre-terminated cabling solutions. These solutions simplify the design and installation of network services by providing high-density, end-to-end systems that deliver quick, plug-in network deployment. This article will guide you to know more about pre-terminated trunk cable assemblies.

Two Types of Pre-terminated Trunk Cables

Corresponding to fiber-based network deployment and copper-based network deployment, there are pre-terminated fiber cabling and pre-terminated copper cabling. The following part will introduce two types of commonly used pre-terminated trunk cable assemblies: pre-terminated fiber trunk cable, and pre-terminated copper trunk cable.

MTP/MPO Trunk Cable

Pre-terminated with MTP MPO connector on both ends, MTP/MPO trunk cable is a cost-effective alternative to time-consuming termination that improves reliability and reduces installation time and cost. It is capable of providing rapid deployment of high density backbones cabling in data centers and other high fiber environments. In networking applications, 12-fiber and 24-fiber MTP/MPO trunk cables are commonly used: 12-fiber MTP/MPO trunk cable is normally for 40G Ethernet network, while 24-fiber MTP/MPO trunk cable is normally for 100G Ethernet network. Since there are different types of MTP/MPO trunk cables on the market, it is important to choose the suitable one provided by reliable MPO trunk cable manufacturers. The following figure shows a high fiber count MTP/MPO trunk cable—72-fiber MTP/MPO trunk cable. There are 6 legs on both ends with each leg terminated with a 12-fiber MTP MPO connector.

72-fiber MTP MPO trunk cable

Pre-terminated Copper Trunk Cable

The pre-terminated copper trunk cable is a bundle of category cables, built with a choice of 6, 12, or 24 cable bundle and factory terminated with jacks and plugs. It allows fast and easy installation with reduced labor costs in large copper infrastructures with high-density cross-connection and patching systems. In recent years, this high-performance trunk cable has become a popular plug-and-play solution in the horizontal distribution area (HDA) to connect switch cabinets to server cabinets, and in the zone distribution area (ZDA) to run from the HDA to zone boxes. The pre-terminated copper trunk cable assemblies on the market are available in pre-bundled and pre-labeled styles, available in Cat 5e, Cat 6 and Cat 6a UTP and STP cable constructions with each available in jack to jack, plug to plug and jack to plug termination ends. Here is a figure of pre-terminated copper trunk cable for you.

pre-terminated copper trunk cable

Benefits of Pre-terminated Trunk Cable Assemblies

There are many benefits of deploying pre-terminated trunk cable assemblies.

High Speed of Deployment

The high speed of deployment offered by pre-terminated trunk cable assemblies is an equally important feature. The quick plug-in connections of network devices allow fiber and copper links to be installed in significantly less time than traditional field-terminated links, resulting in considerable installation-cost reductions. In many cases, pre-terminated trunk cables can cut installation time by up to 80% over field terminations.

Consistent High Levels of Performance

Pre-terminated trunk cable assemblies offer consistent high levels of performance for improved network integrity. Solutions are available that exceed specifications for high data transmission rate performance, providing extra headroom in the channel for data center upgrades and modifications. This level of reliability is crucial in the data center environment, where channel insertion loss budgets are very tight.

No Need for Performance Testing

The transmission testing of pre-terminated trunk cable assemblies is performed by the manufacturer before shipment, and test reports are included with the assemblies. This leaves only continuity testing for copper and 10% insertion loss and continuity testing for fiber, which reduces the time spent testing on-site.

Cut Clean-up Time

Pre-terminated cabling solutions allow for quick clean-up due to minimal leftover materials and scrap. Also, because there is less waste material to clean up, pre-terminated solutions also help meet green design, waste reduction, and material reuse goals.


Pre-terminated trunk cable assemblies provide an ideal plug-and-play solution for links between switches, servers, patch panels, and zone distribution areas in the data center. They can accelerate the process, reduce costs and errors, and can help bring your data center online in less time. If your data center or network application needs speed and testing simplified installation, pre-termination trunk assemblies are perfect.