What is the Meaning of 100G Channels Networks to Service Providers

As the traffic demand continues growing, telecom network providers have planned introducing the newly developed coherent 100G transport software in their networks to satisfy the demand. History shows us that network service providers have made use of every stage of the new channel capacity available from equipment developers.



The figure below shows the timeline for increases in fiber link capacity operating provider’s networks. In early 1990s, a capacity of a few hundred Mbps per link and just on channel per strand of fiber inside a transport network was typical. As email was a new communication tool in the centre 1990s, the fiber capacity gradually increased to a couple Gbps, and this growth continued to deal with the demand that individuals needed to start accessing the web. Into the later 1990s, fiber capacity grew even larger with the deployment of 10 Gbps channels and WDM techniques to multiplex and amplify a small number of wavelengths (4-8) on a single fiber pair. In early 2000s, Internet usage became commonplace but networking kept pace using the introduction of DWDM techniques that could support 40, 80, or maybe more wavelengths allowing fiber capacities to be near Tbps. For MUX/DeMUX solutions with different DWDM wavelengths, please visit Fiberstore. This extensive fiber capacity increase helped the transport network support continually increasing user demands. In the late 2000s, the introduction of 40G channels gave the capability of the networks another boost. By 2010, video sharing on the web by applications such as YouTube along with other video when needed (VoD) services started to stress existing network capacity. The development of the fiber capacity to approximately 10 Tbps per fiber. This will address near term capacity requirements, but moving forward, cloud computing along with other bandwidth hungry applications will continue to consume network resources, and new optical techniques to increase channel capacity and optical link capacity is going to be introduced progressively.


The coherent 100G PM-QPSK system selected by the industry is able to run at the same channel spacing (50 GHz) like a 10G commercial system does in existing networks, and so the 100G system can offer enough capacity for network service providers to support customer demands in the near term without a network overbuild. Using the new 100G system, service providers expect the cost per bit declines in the same rate as or perhaps a faster pace than the decline rate of serves prices service providers can charge their clients, so that providers are able to remain competitive.

Before telecom service providers introduce commercial coherent 100G software in their networks, normally a series of technology trials must be conducted in their existing networks to determine the performance of the new technology. The primary purpose of the technology trials would be to guarantee the 100G channel behaves well in existing fiber network infrastructures. Fiber routes within the field may have high transmission attenuation, high PMD values, multiple connections and splicing points, various fiber types, etc. While most lab experiments are conducted with fiber loop configurations, a linear configuration in field trials is much more preferred to mimic optical links in tangible networks. Field trials give network providers proper expectation for that performance of the systems, which will be installed in networks. Issues present in these trials may also be sent back somewhere developers for further product improvement. In a single field trial a 112 Gbps coherent channel transmitted over 1730 km deployed DWDM link in a service provider’s network, while using DWDM Multiplexer. A carrier suppressed RZ and differential PM-QPSK modulation format was utilized for the channel in the trial. The trial results show that the coherent 100G channel has the capacity to serve long term routes. The plug and play performance of the equipment and robustness to chromatic dispersion and PMD impairments was demonstrated in the trial. Co-propagating the 100G channel with adjacent 10 Gbps signals without touching the fiber infrastructure proved one viable migration road to next generation networks. It’s a requirement for service providers to maintain the networks scalable and cost-effective while increasing channel capacity and fiber ability to have next-gen multi-terabit networks.

In another field trial a real-time, single carrier, coherent 100G PM-QPSK upgrade of the existing 10G/40G terrestrial system was demonstrated inside a service provider’s network. The field experiment shows the performance of the 100G channel sufficient for error-free operation after FEC over installed 900 km and 1800 km fiber links. The experiment proves that flexible and seamless 100 Gps channel upgrades to existing 10G and 40G DWDM systems are possible and practical.

Yet another coherent 100G channel field trial was performed on dispersion shifted fiber (DSF) links. The trial involved eighty 127 Gbps channels propagating on a deployed fiber link. L-band specturn was used to avoid zero dispersion reason for specturn, differnet from using C-band for SMF or NZDSF for additional common cases. The 100G channels, with 50 GHz channel spacing, traveled over 458 km DSF successfully with L-band EDFA only. Sufficient Q-margins remained as left for the 80 channels following the 458 km transmission. This field trial demonstrated that a 10 Tbps calss capacity DWDM product is feasible underneath the condition of small local dispersion by deploying coherent detection and high overhead (20%) coding gain FEC. This trial represented the highest fiber capacity in the field at the time the trial was conducted.

The reason for introducing 100G channels into transport networks is to carry large IP data traffic across IP networks, therefore, an “end-to-end” transport trial, i.e. an entire data transport trial from data equipment to data equipment, using a coherent 100G channel transmission over a long distance, is particularly meaningful to service providers. One such field trial, which involved a worldwide network company, a data equipment developer, a transport equipment developer, and a client interface developer, continues to be reported. In this trial a 112 Gbps single carrier real-time coherent PM-QPSK channel from a transponder carried native IP packet traffic over 1520 km field deployed fiber, with 100GbE router cards and 100G CFP interfaces. This trial shows the feasibility of interoperability between multi-suppliers’ equipment for 100G transport. This field trial, which fully emulated an operating near-term deployment scenario, confirmed that all key components required for deployment of 100GbE technology are maturing at the time the trial was conducted (early 2010).


The detailed configuration of the trial is shown in the figure. A 10GbE test set generates 10GbE traffic for Router 1 and also the test set can be used for analyzing packet throughput too. Another router (Router 2) is used to accept a GbE signal containing a video signal using a video encoder and to send the recording signal to some video display via a video decoder following the signal transverses the trial path. Router 2 connects to Router 1 with another 10GbE link, containing the video traffic. Router 1 routes both 10GbE data streams to one of the 100GbE cards and routes back the 10GbE data streams form the other 100GbE card towards the corresponding 10GbE ports. The 100G CFP interfaces are used to connect 100GbE cards and the 100G transponder. The transmitter port of the CFP in the first 100GbE card is connected to the receiver port of the CFP in the transponder and also the receiver port of the second 100GbE card is linked to yhe transmitter port from the CFP in the transponder. The receiver port from the CFP in the first 100GbE card and also the transmitter port of the CFP in the second 100GbE card are of a fiber jumper (fiber patch cable) to shut the loop. The CFP transponder sends the 112 Gbps signal towards the fiber route-equipped having a long haul DWDM system. Both directions of the inline amplifiers have been used for the trial to save on equipment needed.

With these successful 100G system field trials, telecom network providers and other network operators have been convinced that the only optical carrier PM-QPSK with coherent detections is easily the most promising 100G channel solutions, at least for the time being. Now commercial 100G systems are for sale to the customers of the equipment developers and the customers are likely to enjoy the ten times fiber capacity begin their networks.


What is The Fiber Optic Multiplexer

What is the fiber optic multiplexer? A fiber multiplexer is a device where one input can be routed to many different outputs, usually 16. It utilizes fiber optic technology, is usually controlled by use of software and a rotator block, and has an optical path that is actually coupled through several COL-UV/VIS collimating lenses. So, this is basically what a fiber optic multiplexer is, but what exactly do these devices do, and what are they used for? Well, this is a good question, and here is some information that might help you. But it is hard to tell you everything about a fiber multiplexer in one article, here are some things that might help you to better understand the complex operations of this device.

Basically, fiber optic multiplexers are used at one end of a fiber optic cable so that many, many things can spend information over that same wire. It is like a giant multi-input connector, allowing for several signal inputs that are then sent over a single strand of fiber optic cable. This information travels along this wire until, usually, it comes into contact with a demultiplexer, which is like another attachment at the end of the cable that again splits up the signals and sends them on their way.

One of the most obvious uses for a fiber multiplexer is the fact that it saves a lot of money. Cable is not cheap, but it does have the ability to send several communications over its length at the same time. so, by putting a multiplexer at one end, and a demultiplexer at the other, a company can save a ton of money on fiber optic cable (buy fiber optic cable).

In a way, the ensuing network of information, and the way that it travels, can be compared to a large freeway. This large freeway might connect two very large cities, and in the morning, there might be a ton of traffic that gets on the freeway, it neither actually all came from the exact same place, nor is it all headed in the exact same place.

The traffic trickled onto the freeway from various side roads in one city, and it will exit in the same manner when it reaches its destination. In this way, the illustration is a lot like a fiber multiplexer/demultiplexer system, with the cars being the information, the cities being the multiplexers, and the freeway being the fiber cable.

This is a very basic way to describe how a fiber multiplexer works, but hopefully it helps you understand. It is not an overly tough concept to grasp, even though fiber optics are still a technology that can stump about anybody who does not work with it all the time. The best way to learn about fiber optic cable is to either research it, or to actually work with it in a network or a system. A lot of different industries now make use of the speed with which fiber optic can deliver information. Light travels a lot faster than electric signals, after all.

FiberStore designs, manufactures, and sells a broad portfolio of optical communication products, including passive optical network, or PON, subsystems, optical transceivers (such as sfp transceiver module, xfp transceiver, sfp+ transceiver and more) used in the enterprise, access, and metropolitan segments of the market, as well as other optical components, modules, and subsystems. In particular, FiberStore products include optical subsystems used in fiber-to-the-premise, or FTTP, deployments which many telecommunication service providers are using to deliver video, voice, and data services.

WDM Networks: The Transponder

In optical fiber communications, Optical Transponder sends and receives the optical signal from a fiber. A transponder is typically characterized by its data rate and the maximum distance signal travels.

The transponders are of two types namely transmit transponders and receive transponders. The function of transmit transponder is to convert the incoming optical signal into pre-defined optical wavelength. The transponder (transmit) first converts the optical signal to an electrical signal and performs reshaping, retiming and retransmitting functions, also called 3R functions. The electrical signal is then used to drive the laser, which generates the optical signals having optical wavelength. The output from the all transponders (transmits) is fed to combiner in order to
combine all optical channels in optical domain. In receive transponder, reverse process takes place.

Individual wavelengths are first split from the combined optical signal with the help of Fiber Optical Splitter and then fed to individual receive transponders, which convert the optical signal to electrical, thus 3R function and finally convert the signal back to the optical. Thus the individual channels are obtained. As the output of the transponder is factory set to a particular wavelength, each optical channel requires unique transponder.

Often, fiber optic transponders are used for testing interoperability and compatibility. Typical tests and measurements include jitter performance, receiver sensitivity as a function of bit error rate (BER), and transmission performance based on path penalty. Some fiber optic transponders are also used to perform transmitter eye measurements.

The transponder according to the invention utilises delays that are switchable between different optical fiber lines, so as to be able to select many different lengths without the necessity of re-designing the same transponder. Moreover, the transponder according to the invention uses a Single Side Band (SSB) optical component which produces an optical shift of the frequency of the radar signal, that avoids the drawbacks and solves the problems of the traditional electrical systems. The transponder according to the invention is comprised in multifunctional radar systems and allows at least three different uses: the first is the systems calibration on the basis of moving targets that are simulated in the production step,the second one is the performances test of a radar that has already been calibrated in the step of the system acceptance by the client (Field Acceptance Test), and the third one is the support to the identification of possible faults and nonworking partsof the radar, during the operation life of the same radar system. The transponder of the invention comes out to be easily producible and transportable.

An integrated transponder will also be needed: one transponder that couples to 10 individual fibers at a much lower cost than 10 individual transponders. With a super-channel transponder, several wavelengths are used, each with its own laser, modulator and detector. Photonic integration is the challenge to achieve a cost-effective transponder.

The Difference Between Fiber Optic Transponder And Fiber Transceiver

A transponder and transceiver are both functionally similar devices that convert a full-duplex electrical signal in a full-duplex optical signal. The difference between the two is that fiber transceivers interface electrically with the host system using a serial interface, whereas transponders use a parallel interface. So transponders are easier to handle lower-rate parallel signals, but are bulkier and consume more power than transceivers.