Gigalight 100G Optical Modules Passed the Connectivity Test of Multiple Cloud Service Providers

Shenzhen, China, May 19, 2018 – Gigalight announced the 100G series optical transceiver modules have passed the connectivity test of multiple cloud service providers. The Gigalight 100G series products include 100G QSFP28 SR4 multi-mode VCSEL optical modules and 100G QSFP28 CWDM4 single-mode WDM optical modules. The interconnection test covers the mainstream cloud devices of major brand equipment vendors and the optical transceiver module products of our partners.

Qualified 100G Series Optical Transceiver Modules

Gigalight has always been among the top 10 companies in the world of optical interconnects with its invention of active optical cables and deep innovation. However, Gigalight is essentially an integrated solution provider of optical transceiver modules and optical network devices. Gigalight ships a large number of 10G multimode and 10G single-mode optical modules and 40G multimode SR4 optical modules to the world. In the field of 40G single-mode optical modules, Gigalight's main customers include global TIE1 equipment vendors. The cloud service providers have directly verified Gigalight's 100G optical modules since the end of 2017. The successful interconnection results so far have greatly encouraged Gigalight's confidence in deploying 100G optical modules in bulk in the cloud.

Global Data Center Infrastructure Ecosystem

Global Data Center Infrastructure Ecosystem

Gigalight has a deep optical interconnect product line. Among this product line, the multimode optical interconnect products based on the VCSEL technology applications are the traditional advantages of Gigalight, including the cost-effective and reliable 100G QSFP28 SR4 optical modules with good compatibility. The single-mode 100G series short-range optical modules were developed in 2016 and this time passed the threshold of full-brand compatibility and interoperability testing after optical design thresholds and reliability verification thresholds. Finally, they will not lose pace in the industry's striding forward in 2018.

As a global optical interconnect design innovator, Gigalight has prepared the best 100G optical modules for industry users.

About Gigalight:

Gigalight is a global optical interconnection design innovator. We design, manufacture and supply various kinds of optical interconnect products including optical transceivers, passive optical components, active optical cables, GIGAC™ MTP/MPO cablings, and cloud programmers & checkers, etc. These products are designed for three main applications which are Data Center & Cloud Computing, Metro & Broadcast Network, and WIreless & 5G Optical Transport Network. Gigalight takes the advantages of exclusive design to provide customers with one-stop optical network devices and cost-effective products.


What is Data Center Interconnect/Interconnection?

Data Center Interconnection means the implements of Data center Interconnect (DCI) technology. With the DCI technology advances, better and cheaper options have become available and this has created a lot of confusion. This is compounded by the fact that a lot of companies are trying to enter this market because there is a lot of money to be made. This article is written to straighten out some of the confusion.

According to the different applications, there are two parts of data center interconnections. The first is intra-Data Center Interconnect (intra-DCI) which means connections within the data center. It can be within one building or between data center buildings on a campus. Connections can be a few meters up to 10km. The second is inter-Data Center Interconnect (inter-DCI) which means connections between data centers from 10km up to 80km. Of course, connections can be much longer but most of the market activity for inter-DCI is focused on 10km to 80km. Longer connections are considered Metro or Long-haul. For reference, please see the table below.

DCI Distance Fiber Type Optics Technology Optical Transceivers
intra-DCI 300m MMF NRZ/PAM4 QSFP28 SR4
500m SMF QSFP28 PSM4
2km QSFP28 CWDM4
10km QSFP28 LR4
inter-DCI 10km SMF Cohernet QSFP28 4WDM-10
20km QSFP28 4WDM-20
30km to 40km QSFP28 4WDM-40
80km to 2000km CFP2-ACO


The big bottlenecks are in the intra-DCI and therefore, the highest volume of optical transceivers are sold here generating the most revenue, however, it is low margin revenue because there is so much competition. In this space, may of the connections are less than 300m and Multi-Mode Fiber (MMF) is frequently used. MMF is thicker, and components are cheaper because the tolerances are not as tight, but the light disperses as it bounces around in the thick cable. Therefore, 300m is the limit for many types of high speed transmission that use MMF. There is a data center transceiver with a transmission distance up to 100m over OM4 MMF for example.

Gigalight 100GBASE-SR4 100m QSFP28 Optical Transceiver

100G QSFP28 SR4 for MMF up to 100m

In a data center, everything is connected to servers by routers and switches. Sometimes a data center can be one large building bigger than a football field and other times data centers are built on a campus of many buildings spanning many blocks. In the case of a campus, the fiber is brought to one hub and the connections are made there. Even if the building you want to connect to might be 200m away, the fiber runs to a hub, which can be more than 1km away, so this type of routing increases the fiber distance. Some of the distances between buildings can be 4km, requiring Single Mode Fiber (SMF), which has a much narrower core, making it more efficient, but also increasing the cost of all related components because the tolerances are tighter. Therefore, with data centers growing, so has the need for SMF as the connections get longer within the data center. With SMF you have the option to drive high bandwidth with coherent technology, and we'll see more of this in the future. Previously coherent was only used for longer distances, but with cost reductions and greater efficiency versus other solutions, coherent is now being used for shorter reaches in the data center.

Gigalight 100GBASE-LR4 Lite 4km QSFP28 Optical Transceiver

100G QSFP28 LR4L for SMF up to 4km

500m is a new emerging market and because the distance is shorter, a new technology is emerging, and that is silicon photonics modulators. EMLs (Externally Modulated Lasers) perform modulation within the laser, but with silicon photonics, the modulator is outside the laser and it's a good solutions for distances of 500m. In an EML, the modulator is integrated into the same chip, but is outside the laser cavity, and hence is "external". For silicon photonics, the laser and modulator are on different chips and usually in different packages. Silicon photonics modulators are based on the CMOS manufacturing process that is high scale and low cost. A continuous wave laser with silicon photonic modulation is very good for 500m applications. EMLs are more suitable for longer reaches, such as 2-10km. Therefore, with data centers growing, so has the need for single mode fiber as the connections get longer within the data center. With SMF you have the option to drive high bandwidth with coherent technology, and we'll see more of this in the future. Previously coherent was only used for longer distances, but with cost reductions and greater efficiency versus other solutions, coherent is now being used for shorter reaches in the data center.

100GE PSM4 2km QSFP28 Optical Transceiver

100G QSFP28 PSM4 for SMF up to 500m/2km

100GE CWDM4 2km QSFP28 Optical Transceiver

100G QSFP28 CWDM4 for SMF up to 2km

100GBASE-LR4 10km QSFP28 Optical Transceiver

100G QSFP28 LR4 for SMF up to 10km


Inter-DCI is typically between 10km and 80km, including 20km and 40km. Before we talk about data center connectivity, let's talk about why data centers are set up the way they are and why 80km is such an important connection distance. While it is true that a data center in New York might backup to tape in a data center in Oregon, this is considered regular long-haul traffic. Some data centers are geographically situated to serve an entire continent and others are focused on a specific metro area. Currently, the throughput bottleneck is in the metro and this is where data centers and connectivity are most needed.

100GE 4WDM-20 20km QSFP28 Optical Transceiver

100G QSFP28 4WDM-20 for SMF up to 20km

100GE 4WDM-40 40km QSFP28 Optical Transceiver

100G QSFP28 4WDM-40 for SMF up to 40km

Say you have a Fortune 100 retailer and they are running thousands of transactions per second. The farther away a data center is, the more the data is secure because the data center is so far away and separate from natural disasters, but with the increased distance there are more "in flight" transactions are at risk of being lost due to latency. Therefore, for online transactions there might be a primary data center that is central to retail locations and a secondary data center that is around 80km away. It's far enough away not to be affected by local power outages, tornadoes, etc, but close enough that there is only a few hundred milli-seconds of latency; therefore, in the worst case a small number of transactions would be at risk.

In another example of inter-DCI, as if a certain video is getting a lot of views, the video is not only kept in its central location, but copies of the video are pushed to metro data centers where access is quicker because it's stored closer to the user, and the traffic doesn't tie up long haul networks. Metro data centers can grow to a certain size until their sheer size becomes a liability with no additional scale advantage and thus they are broken up into clusters. Once again, to guard against natural disasters and power outages, data centers should be far away. Counterbalancing this, data centers need to have low latency communication between them, so they shouldn't be too far away. There is a compromise and the magic distance is 80km for a secondary data center, so you'll hear about 80km data center interconnect a lot.

It used to be that on-off keying could provide sufficient bandwidth between data centers, but now with 4K video and metro bottlenecks, coherent transmission is being used for shorter and shorter distances. Coherent is likely to take over the 10km DCI market. It has already taken over the 80km market but it might take time before coherent comes to 2km. The typical data center bottlenecks are 500m, 2km, and 80km. As coherent moves to shorter distances, this is where the confusion comes.

The optical transceiver modules that were only used within the data center are gaining reach, and they're running up against coherent solutions that were formerly only used for long distances. Due to the increasing bandwidth and decreasing cost, coherent is being pulled closer into the data center.

The other thing to think about is installing fiber between data centers. Hopefully this is already done, because once you dig, it's a fixed cost, so you put down as many fibers as you can. Digging just for installing fiber is extremely expensive. In France when they lay fiber, they use another economic driver. Whenever you put in train tracks, you put in fiber at the same time, even if it is not needed. It's almost for free because they are digging anyway. Fibers are leased to data centers one at a time; therefore, data centers try to get as much bandwidth as possible onto each fiber (this is also a major theme in the industry). You might ask, why not own your own fiber? You need to have a lot of content to own your own fiber. The cost is prohibitive. In order to make the fiber network function, all the nodes need to use the same specification and this is hard. Therefore, carriers are usually the ones to install the full infrastructure.

Article Source: John Houghton, a Silicon Valley entrepreneur, technology innovator, and head of MobileCast Media.


Gigalight Launches 40km 100G Single Receiver Optical Modules for DPI

Shenzhen, China, May 8, 2018 − Recently, Gigalight has launched two 40km single receiver optical modules, the 100G QSFP28 ER4 Lite Receiver and the 100G CFP2 ER4 Receiver, as a new solution for Deep Packet Inspection (DPI) applications.

With the rapid development of IP network (Cloud Computing etc.) and high bandwidth growth, various application requirements based on IP, such as monitoring, auditing and traffic analysis, have become increasingly complex. The optical interface of the front-end flow collection and distributary equipment has been upgraded from the past 10GE to the present 100GE ports. When the flow collection equipment can not be placed in the same room of the collected equipment, and the long distance fiber transmission is needed after the signal splitting, users have to face the challenge of the excessive attenuation of the optical signal. The usual practice is to add optical amplifiers, such as EDFA, on the optical link, but this will result the problems of cost and maintain. Howeverm, the flow collection equipment only needs to collect the optical signals, which means receiving only. In response to this feature, Gigalight has developed two 40km 100G single receiver optical modules of different packages to respond to different customer needs.

The first one is the single receiver 100G QSFP28 ER4 Lite optical module with a power dissipation less than 2.5W. It uses a high-sensitivity APD detector (ROSA) with a receiving sensitivity up to -15dBm per channel (1E-12, @25G). This module increases the optical transmission budget for users and meets the optical transmission applications (optical fiber directly connected without splitting) up to 40km when the Forward Error Correction (FEC) function in the front of the system side is enabled.

Single Receiver High-Sensitivity 100G QSFP28 ER4 Lite Optical Module

The second one is the single receiver 100G CFP2 ER4 optical module with a power dissipation less than 3.5W. It uses the PIN photodetector (ROSA) and the miniaturized Semiconductor Optical Amplifier (SOA). At the same time, it adopts the SOA closed-loop adaptive gain control algorithm developed by Gigalight, which can quickly lock the working current of SOA and quickly adjust the amplification performance of SOA, to ensure that the receiver's acceptance sensitivity is as high as -21.4dBm per channel (1E-12, @25G). Even when the FEC function of the system side is disabled, it can also meet the optical transmission applications (optical fiber directly connected without splitting) up to 40km, fully compliant with the IEEE 802.3ba 100GBASE-ER4 standard and the ITU-T G.959.1 OTU4 (4L1-9C1F) standard that is more stringent.

Single Receiver High-Sensitivity 100G CFP2 ER4 Optical Module

Wiith the advantage of the Gigalight 40km 100G single receiver modules' high sensitivity feature, users do not need to pay more on the relay optical amplification equipment, thereby reducing the operating cost and providing an economical solution for the long distance application of the 100GE ports between the machine rooms.

Gigalight has built a comprehensive portfolio for single receiver 100GE optical modules, including 100G QSFP28 LR4 Rx only, 100G CFP2 LR4 Rx only, 100G QSFP28 ER4 lite Rx only (New), and 100G CFP2 ER4 Rx only (New). These products have greatly met customers' choice of 100G product diversity. At the same time, through technological innovation, the self-developed 100G ROSA components have been adopted to achieve the cost advantage, thus bringing the practical benefits to manufacturers of flow collection and distributary DPI equipment.

About Gigalight:

Gigalight is global optical interconnection design innovator. A series of optical interconnect products include: optical transceivers, passive optical components, active optical cables, GIGAC™ MTP/MPO cablings, and cloud programmers & checkers, etc. Three applications are mainly covered: Data Center & Cloud Computing, MAN & Broadcast Video, and Mobile Network & 5G Optical Transmission. Gigalight takes advantage of its exclusive design to provide clients with one-stop optical network devices and cost-effective products.

Article Source: http://www.gigalight.com/news_detail/newsId=429.html


Introduction on 5 Kinds of 40G QSFP+ Optical Transceivers

40G optical transceivers are a series of optical transceivers with 40Gbps transmission rate, in which CFP and QSFP are the main form factors. And the 40G QSFP+ optical transceivers are one of the most widely used optical transceivers. In the post, Gigalight will introduce you several kinds of most popular 40G QSFP+ optical transceivers that can help you have a better choice.

1. 40G LR4 QSFP+

The 40G LR4 QSFP+ optical module is typically used with LC single-mode fiber patch cables for transmission distances up to 10km, and it has 4 data channels that transmit data simultaneously. The advantages of 40G LR4 QSFP+ optical modules are high density, low cost, high speed, large capacity, and low power consumption.

The working principle of 40G LR4 QSFP+ optical module: The laser driver controls the arrival wavelength, the optical signal passes through the multiplexer and is combined together for transmission. When arriving at the receiving end, these transmitted signals are then demultiplexed by the demultiplexer into four channels with a transmission rate of 10 Gbps. Then the PIN detector or transimpedance amplifier recovers the data stream and transmits the optical signal.

2. 40G SR4 QSFP+

The 40 G SR4 QSFP+ optical modules are often used with the MPO/MTP connector in 40G data transmission. It has four independent full-duplex channels and is also transmitted through four channels. The transmission rate is the same as that of the LR4. The difference is that the 40 G SR4 QSFP+ optical modules are often used with multimode optical fiber. The transmission distance when using it with the OM3 optical fiber jumper is 100m, and the transmission distance when using it with the OM4 optical fiber jumper is 150m.

The working principle of the 40GBASE-SR4 optical module: when the transmitting end transmits a signal, the electrical signal is first converted into an optical signal via a laser array. When the transmitting end transmits a signal, the photodetector array converts the parallel optical signal when the receiving end receives a signal.

As a highly integrated 4-channel optical module, the 40 G LR4 PSM optical modules have the advantages of high port density and low cost. The optical port of this optical module adopts the parallel single-mode technology-PSM. It uses a 4-way parallel design MPO/MTP interface and the transmission distance is 10km.

The work principle of 40 G LR4 PSM optical modules is in the same way as the 40 G SR4 QSFP+ optical modules. The difference is that 40G LR4 PSM optical modules are often used to connect with single-mode ribbon fiber connectors. That is, parallel optical signals are sent in parallel through eight single-mode optical fibers.

4. 40G QSFP+ DAC

The 40G QSFP+DAC high-speed cable consists of two 40G QSFP+ optical transceivers and a copper cable.

DAC advantages:

(1) Low cost, reducing the impact of dust and other contaminants on optical cables, and improving transmission efficiency;

(2) The high-speed cable is made of copper core, which has good heat dissipation effect and is energy-saving and environmentally friendly.

(3) High-speed cables consume low power.

5. 40G QSFP+ AOC 

The 40G QSFP+AOC active optical cable is the core component of the parallel optical interconnection. It is composed of two 40G QSFP+ optical transceivers connected by a ribbon optical cable.

The QSFP+AOC active optical cable is an efficient integrated fiber optic cable assembly designed for short-range, multi-channel data communication and interconnection applications. Each signal direction has four data channels with a rate of 10 Gbps per channel.

AOC advantages:

(1) The transmission power is lower, so the power consumption is small;

(2) Weight and volume are much smaller than high-speed cables;

(3) The transmission distance is farther (it can reach 100-300 meters).

In Conclusion

The above five kinds of optical modules are available from Gigalight. When you use the optical module purchased in Gigalight, your device's stability and network speed will be greatly improved. If you want to learn more about optical module solutions, please visit Gigalight official website to view.


Introduction on 25G/50G/100G Ethernet

The rise of cloud computing and the expansion of the data center are pushing the latest Ethernet speeds up, while big data based on cloud technology has already added to carriers' workloads. To meet this requirement, the data center extends the bandwidth capabilities that are parallel to existing infrastructure. Rapid growth in the expected 25G and 100G Ethernet deployments is a testament to this trend.

In order to be able to handle the increasing data load, the industry's largest long-distance cloud companies have together with their core network's data center operators, to jointly use the 100G Ethernet architecture. However, most operators believe that 100G or even 40G is somewhat excessive for server connections because its workload only needs to be incrementally improved over 10G networks. This is why, although 40G and 100G Ethernet have been introduced, 25G and 50G Ethernet are still one of the reasons for the common choices within the data center. Below we will briefly explain why 25G is more suitable for these applications than 40G.

Several recent Ethernet bandwidth technologies are not designed to set a new high speed, but more to push such network protocols into adjacent markets, especially the data center market. Below we will explain the specific reasons by introducing 25G, 50G and 100G respectively.

25G Ethernet

The official draft of the IEEE 802.3 draft standard for 25G Ethernet will eventually be completed in 2016, and it will mainly be aimed at servers in cloud data centers. This is a relatively short time frame due to the reusable components of 10G and 100G Ethernet.

40G and 100G already exist, but why use 25G? This confused some operators. The answer lies in the requirements of architecture and performance. The existing 100G standard network system consists of four links, each of which has a bandwidth of 25 Gbps. This four-to-one ratio is equivalent to connecting servers to 25G switches and then converging to 100G uplinks, which helps network operators to more easily expand their data centers.

Similarly, 40G Ethernet is composed of four 10G Ethernet links. However, according to John D’Ambrosia, chairman of the Ethernet Alliance, many data centers have adopted more than 10G servers. This is why a number of chip vendors have provided 25G serial/deserializer transceivers. This will not only make bandwidth convergence for 25G, 50G, and 100G Ethernet more convenient, but also reduce costs due to volume.

50G Ethernet

Although the implementation of the IEEE standard for 50G Ethernet is still some time away (approximately 2018 to 2020), many industry alliances expect that products will begin to appear in 2016. Similar to 25G technology, 50G Ethernet technology will be the next solution for high-speed connection servers and data centers. According to analyst firm's Dell’Oro data, over the next few years, servers and high-performance flash storage systems will need to exceed 25G.

To help deliver these accelerated Ethernet technology products faster, the 25G/50G Ethernet Alliance has eliminated the royalty fees for the 25G and 50G Ethernet specifications and is open to all data center ecosystem vendors.

Reusing the 25G components of the existing 100G network can reduce the implementation cost of 50G. For example, the cost structure of 25G cabling is the same as 10G, but its performance is 2.5 times. Similarly, 50G costs half of the 40G cost, but performance can be increased by 25%.

100G Ethernet

For long-distance carrier networks ranging from hundreds of kilometers to tens of thousands of kilometers, the deployment of 100G Ethernet will continue to grow.
But according to information provided by a new industry alliance, the 100G architecture will be another excellent market alternative. The 100GCLR4 alliance led by Intel and Arista Network believes that 100G is ideal for connecting large "ultra-large" data centers spanning 100 meters to 2 kilometers.

Other companies are also seeking alternative 100G implementations for the data center. Sinovo Telecoms has joined the CWDM4 MSA industry consortium, which aims to define a common specification for low-cost 100G optical interfaces within 2 kilometers of data center applications. With the transformation of network infrastructure to 100G data rates, data centers will require long-range, high-density, 100G embedded optical connections. The MSA uses Coarse Wavelength Division Multiplexing (CWDM) technology to provide four 25G single-mode fiber (SMF) link channels. Similarly, the OpenOpTIcsMSA organization initiated by Ranovus and Mellanox Technologies will also focus on developing a data center supporting 2 kilometers of 100G.

In the past, the increase in speed has driven the development of most network components. Today, to handle the massive data flow through the cloud, companies need to seek a balance between speed-up and reuse technology to find a cost-effective solution. Gigalight, as a professional optical transceiver vendor, can provide various kinds of optical transceivers to meet your 25G/50G/100G/200G/400G transmission needs. For more details, please visit its official website.


Tips on Using Optical Transceivers

Optical transceiver consists of optoelectronic devices, functional circuits, and optical interfaces. The optoelectronic devices include transmit and receive parts. The transmitting part is: Inputting a certain bit rate of the electric signal is processed by an internal driver chip to drive a semiconductor laser (LD) or a light emitting diode (LED) to emit a corresponding rate of modulated optical signal, and an internal optical power automatic control circuit is provided therein. The output optical signal power remains stable. The receiving part is: After a certain code rate of the optical signal input transceiver is converted into an electrical signal by the light detecting diode. After the preamplifier outputs the corresponding rate of the electrical signal, the output signal is generally PECL level. At the same time, an alarm signal will be output after the input optical power is less than a certain value.

Today Gigalight will share with everyone some tips on using optical transceivers if you usually pay attention to the maintenance of the optical transceiver. Note that the following two points can help you reduce the loss of the optical transceiver and improve the performance of the optical transceiver.

Note One:

1. There are CMOS devices in this chip. Pay attention to prevent static electricity during transportation and use.

2. The device grounding should be good, reduce parasitic inductance.

3. As far as possible manual welding, if you need to paste, control the reflow temperature cannot exceed 205℃.

4. Do not lay copper below the optical transceiver to prevent the impedance from changing.

5. The antenna should be away from other circuits to prevent radiation efficiency becomes lower or affect the normal use of other circuits.

6. The transceiver should be placed as far away from other low-frequency circuits, digital circuits.

7. It is recommended to use magnetic beads for the isolation power of the transceiver.

Note Two:

1. Do not look directly into the optical transceiver that has been inserted into the device (whether it is a long-range or short-range optical transceiver) with naked eyes, and avoid eye burns.

2. When using a long-distance optical transceiver, the transmit optical power is generally greater than the overload optical power. Therefore, it is necessary to pay attention to the length of the optical fiber and ensure that the actual received optical power is less than the overload optical power. If the length of the optical fiber is short, use a long-range optical transceiver and use it with light attenuation. Be careful not to burn out the optical transceiver.

3. To better protect the optical transceiver from cleaning, it is recommended that you plug the dust plug when it is not in use. If the optical contact is not clean, it may affect the signal quality, it may also lead to link problems and error codes.
4. Rx/Tx, or arrow in and out directions is generally marked on the optical transceiver to facilitate identification of the transceiver. Tx at one end must be connected to Rx at the other end, otherwise the two ends cannot be linked.

Read the above notes, whether do you have a new understanding of the use of optical transceivers? It is important to be helpful to everyone and thank you for your support and attention to Gigalight. For more product details, please visit our official website.


What Can Pluggable Optical Transceivers Do in Data Centers?

For data centers, fiber-optic technology is no longer an option, or is only used to solve the most difficult interconnection problems. Today, high broadband, high port density and fiber optic technology are needed to solve low power requirements, and the current optical fiber technology is a kind of batch production technology, low cost, and is widely used in various applications such as switches interconnect and server interface. And in this post, Gigalight will introduce what pluggable optical transceivers can do in data center in detail.

1. Extend Data Center Distance

From 100Mb/s to 100Gb/s, single-channel 25G Ethernet optical transceivers lead the optical transceiver market of next-generation servers and switches. 40G QSFP+ products can support transmission distances up to 300m over multimode optical fibers, which greatly exceeds the standard distance of IEEE 40G Ethernet. In the 40 KM 40G QSFP+ product that transmits on single-mode fiber, and the 10 GSFP+ product that transmits 80 km, our OIF module or CFP2-ACO module supports a transmission distance of 500km or more for data center metro or intercity connectivity.

2. Increase Density and Reduce Power Consumption

Our products are at the leading edge of the next generation of low-power optical transceiver products. The 100G QSFP28 optical transceivers (SR4, LR, CWDM4, and SDWM4) have a maximum power consumption of only 3.5W. The 40G and 100G Quad wire active fiber optic products have power settings that can be flexibly configured by the host system.

3. Deploy with Existing Multimode Fiber

Most data centers today are still based on the 10G Ethernet architecture and use 10Gbase-SR short-haul transmission over OM3/OM4 duplex multimode fiber. With the data center upgrading from 10G to 40G or even 100G, customers still want to retain the existing multi-mode fiber architecture. However, SR4 optical transceivers need to be connected with ribbon multimode optical cables (multi-core) on the interface, and LR4 optical transceivers need to be double. Single-mode fiber, both of which are not present in the data center of currently deployed duplex multimode fiber, QSFP+ LM4 modules allow customers to implement 40 links over existing duplex multimode fiber, SWDM4 modules for customers in the the existing affordable dual-mode multimode fiber architecture enables 40G and 100G Ethernet transmission solutions.

4. From 100G to 200G/400G

Since 2010, the 100G Ethernet optical transceiver has been in a leading position in the market, supplying a large number of CFP optical transceivers for the operator's routers and transmission systems. Since then, we have continued to expand 100G products and developed and supplied CFP2, CFP4, Modules such as CXP and 100G QSFP28 should be widely used in telecommunication, emerging data centers, and 100G systems in enterprise networks. However, we have not stopped our steps. At present, we are actively leading the development of industry standards and the development of next-generation Ethernet products, including 200G and 400G-rate products that will meet the long-term technical requirements for future high-performance data centers.


What Optics Products Are Needed in 5G Fronthaul?

In the past few years, Telecom operators have already upgraded their LTE networks by using additional spectrum, carrier aggregation and LTE-A, and have added Small Cell in Macrocell coverage area to drive the increasement of fronthaul bandwidth requirements. In the current, many operators and equipment vendors have standardized the multi-rate transceivers that support 10Gb/s for all fronthaul requirements. Because they are able to meet most of different transmission speed requirement by one device and decrease the complexity of the specific site design and spare part inventory. Many operators, especially those that lease their fronthaul fiber, also deployed WDM system in their fronthaul networks.

5G Fronthaul Will Need Faster Optical Products, But How Fast?

With the emergence of 5G mobile network, the fronthaul demand will also change. The target peak bandwidth of 5G is 20Gb/s, which will require a higher spectrum than LTE to realize the requirement. That is to say, the shorter wavelength can realize the smaller antenna in the millimeter wave range, thus allows the use of higher order MIMO antenna arrays. In LTE area, 4*8 and 8*8 MIMO have been top. But in 5G area, 64*64 MIMO is also possible. The number of MIMO is higher; the bandwidth required for the corresponding fronthaul link is larger. In the case that other conditions are same, the second way for 5G to increase bandwidth is to use 100 GHz frequency (LTE uses 20GHz), so that can produce a single radio transmission from cellular site to the core network for more than 5 times of bandwidth.

Given the fronthaul bandwidth required to support 5G radio may be have a substantial growth, mobile device manufacturers update the CPRI specification to "eCPRI" (released in August 2017). One key factor of eCPRI is to transfer some physical layer signal processing from the baseband unit to the radiofrequency pull head (RRH), which in many cases reduces the fronthaul bandwidth to one in ten.

When all the different factors that influence the bandwidth of the 5G fronthaul add up (some drive its growth, some drive it down), the expected bandwidth fall in the 14 Gb/s to 30 Gb/s range, depending on the eCPRI implementation details, base stations, and etc. If the old CPRI scheme is adopted, all physical layer signal processing will remain in the baseband unit, and similar 5G network configuration will require 236Gb/s fronthaul bandwidth. As a result, the 5G base station will generate 160Gb/s or more in nominal terms, and with eCPRI, the actual fronthaul bandwidth required will be 14-30Gb/s.

Just like that 10G optical transceivers can become the actual standard for LTE fronthaul, the next generation of higher standard Ethernet speeds will be applied to 5G fronthaul, which means that 5G deployment will require a large number of 25GbE devices. Even though some components are industrial temperature and/or bidirectional versions specially designed for fronthaul application.

5G Network Will Also Need Higher-speed Optics Products( 25Gb/s or above)

Mobile fronthaul or backhaul need 50G, 100G or even 400G optical transceivers. CPRI alliance has defined fronthaul for a long time, but there is no a consistent definition for wireless backhaul. LightCounting defines the backhaul as the first optical link that begins in BBU and carries the flow from the core network. Other broader definitions include access, aggregation, and core networks. Naturally, if the data flow from BBU to the core network flows to 25Gb/s, then 50G, 10G, or even 400Gb/s transfers may be needed.


A Brief Introduction on 4WDM (4 Wavelength Division Multiplexing)

With the rapid development of data centers and mobile base station, 100G optical transceivers are playing a more and more important roles in the data center construction and mobile backhaul. In order to meet the increasing needs for cost-effective and low-power 100G optical networks, 4WDM came out, which is a new module and cage/connector system that supports to transmit up to 40km. In this article, we will introduce you something about 4WDM that you may be interested in.

1. What Is 4WDM MSA

4WDM MSA (4 Wavelength Division Multiplexing Multi-Source Agreement) defines 4 x 25 Gbps Local Area Network Wavelength Division Multiplex (LAN- WDM) optical interfaces for 100G optical transceivers for Ethernet applications including 100 GbE. Forward error correction (FEC) is a link requirement in order to ensure reliable system operation. Two transceivers communicate over single mode fibers (SMF) of length from 2 meters to at least 20 or 40 kilometers. The transceiver electrical interface is not specified by this MSA but can have, for example, four lanes in each direction with a nominal signaling rate of 25.78125 Gbps per lane.

Different form factors for the transceivers are possible. The QSFP28 module is expected to be a popular form factor for these applications. Other form factors are possible and are not precluded by this MSA.

2. Introduction on 4WDM MSA Group

The 4WDM MSA Group is an industry consortium dedicated to defining optical specifications and promoting adoption of interoperable 100G (4x25G) optical transceivers for 10 km based on the CWDM4 wavelength grid, and for 20 km and 40 km based on the LAN-WDM wavelength grid, over duplex single-mode fiber (SMF). These extended reaches are important for modern data center interconnects and mobile backhaul applications. The 4WDM MSA Group is responding to previously unmet industry needs for longer reaches, lower costs, and lower power consumption as compared to previously available standards such that they are implementable in small form factors.

Members of the 4WDM MSA include Applied Optoelectronics, Broadcom, Brocade, Ciena, ColorChip, Dell, Finisar, Foxconn Interconnect Technology, Huawei Technology, Inphi, Intel, Juniper Networks, Kaiam, Lumentum, MACOM Technology, NeoPhotonics, Oclaro, Skorpios Technologies, Source Photonics, and Sumitomo Electric Industries.

3. 4WDM vs. CWDM4

4WDM MSA defines CWDM4 and 4WDM with different distances and wavelengths (2km/10km/20km/40km). 2km and 10km use CWDM wavelength. 20km and 40km use LAN WDM wavelength.

With the different size of the CWDM and LAN WDM wavelengths, the wavelength-transmitting TOSA for LAN WDM must be carried with a TEC (Thermo Electric Cooler). As the stable wavelength drifts with temperature, TEC consumes an extra 0.5W of power, so the overall power consumption of optical transceivers with LAN WDM wavelengths will be higher than that of CWDM optical transceivers.

4. 100G QSFP28 4WDM 40KM

100G QSFP28 4WDM 40KM is a 100Gb/s transceiver module designed for optical communication applications compliant to QSFP28 4WDM 40KM MSA standard. The module converts 4 input channels of 25Gb/s electrical data to 4 channels of LAN WDM optical signals and then multiplexes them into a single channel for 100Gb/s optical transmission. Reversely on the receiver side, the module de-multiplexes a 100Gb/s optical input into 4 channels of LAN WDM optical signals and then converts them to 4 output channels of electrical data. Ethernet applications are up to 30km links without FEC and up to 40km links with FEC interconnections.

Main Features:

  • 4 channels full-duplex transceiver modules
  • Supports data rate up to 103.1Gb/s
  • Supports QSFP28 4WDM 40km MSA
  • 4 x 25Gb/s DFB-based LAN-WDM Cooling transmitter
  • 4 channels APD ROSA
  • Internal CDR circuits on both receiver and transmitter channels
  • Low power consumption <4.2W
  • Hot Pluggable QSFP form factor
  • Up to 30km reach for G.652 SMF without FEC
  • Up to 40km reach for G.652 SMF with FEC
  • Duplex LC receptacles
  • Built-in digital diagnostic functions
  • Operating case temperature 0°C to +70°C
  • 3V power supply voltage
  • RoHS 6 compliant(lead free)


With the advantages of cost-effectiveness, low power consumption as well as long transmission distance, we can look forward that 100G QSFP28 4WDM will have a good performance on 100G optical networks. Gigalight recently released the latest 100G QSFP28 4WDM optical transceiver supporting 100GE applications. For more product details, welcome to visit our official website.

About Gigalight:

Gigalight is a design innovator in global optical interconnect field. A series of optical interconnect products include: optical transceivers, passive optical components, active optical cables, GIGAC MTP/MPO cablings, and cloud programmers & checkers, etc. Three applications are mainly covered: Data Center & Cloud Computing, MAN & Broadcast Video, and Mobile Network & 5G Optical Transmission. Gigalight takes advantage of its exclusive design to provide clients with one-stop optical network devices and cost-effective products.


Ethernet vs. Wi-Fi: Which One Is the Better Choice?

Now we are living in a networking world. Using Ethernet or Wi-Fi can help us to get better wireless network experience. However, we often feel confused while choosing between Wi-Fi and Ethernet. Which one shall I choose? What factors shall be taken into consideration before selecting one of them? Both of the two connections have their own advantages and disadvantages. And these pros and cons are based on some different factors, like speed, security, reliability, latency, etc. Here Gigalight is going to discuss all of the factors in detail below.

Firstly, we need to make it clear that the definition of Ethernet and Wi-Fi before comparing them.

What Is Ethernet and What Is Wi-Fi?

Ethernet is a way of connecting computers together in a local area network or LAN. It has been the most widely used method of linking computers together in LANs since the 1990s. Ethernet is created by Xerox, and jointly developed into the one by Xerox, Intel and DEC. It adopts the CSMA/CD access control method and is conformed to IEEE802.3.

Wi-Fi is the technology that allows a PC, laptop, mobile phone, or tablet device to connect at high speed to the internet without the need of physical wired connection. Wi-Fi uses radio signals to transmit information between your Wi-Fi enabled devices, like your mobile phone, and the internet, allowing the device to receive information from the web in the same way that a radio or mobile phone receives sound.

What’s the Difference between Ethernet and Wi-Fi?

When discussing Ethernet vs. Wi-Fi, there are many differences that can be considered which form the deciding factors in choosing one over another. Some users prefer speed, some users prefer reliability, some users consider security, and some users always like the latest technology. Therefore, the following part will introduce the main differences between Ethernet and Wi-Fi that affect people’s choices.

1. Speed

Wi-Fi has become pretty fast over the years with standards such as 802.11ac and 802.11n being able to give us speeds of 866.7 Mb/s and 150 Mb/s, respectively. That is pretty fast and meets most of our needs, especially when it comes to using the internet.

What about the speed of an Ethernet cable? There are standards for Ethernet cables like cat-5, cat-5e, cat-6 cables etc. Theoretically, a wired Ethernet connection can offer up to 10 Gb/s if you have cat-6 cable. However, the most common cat-5e cable supports up to 1 Gb/s. Ethernet is faster, this is undoubtedly true. If you’re using multiple devices, such as a server where all your data is stored or for LAN gaming, you might consider switching to an Ethernet cable.

2. Reliability

Talking about reliability, Wi-Fi is less reliable of the two. Because a number of things can affect a wireless signal, from other wireless devices to physical objects and walls. This interference can cause dropped signals, higher latency and even lower speeds at times. While it doesn’t matter much when all you need to do is stream content over the internet but for any other purposes, You can minimize this by ensuring your router is placed in the optimum position in your home, but it’s unlikely that you will ever achieve the same levels of stable performance that you will get from Ethernet.

3. Security

When comparing Ethernet vs. Wi-Fi, security is another big factor that needs to be considered. The data on an Ethernet network can only be accessed by devices physically attached to the network. These devices, including the laptop at one end and router at the other, need firewalls to protect them, but there’s way the data itself can be intercepted on the network.

With Wi-Fi, the data is in the air. If you’re using an open network (such as in a coffee shop) then all the data you send and receive can be intercepted, including personal information and login details. That is to say, it is easier to hack into a Wi-Fi network than getting a physical access to the physical Ethernet cable.


Of course there are other factors considering when you want to choose Ethernet or Wi-Fi, like latency, interference, and so on. Generally speaking, Ethernet offers the advantages of better speed, lower latency, and more reliable connections. Wi-Fi offers the advantage of convenience and being good enough for most uses. So, you can choose one of them according to your actual use.

About Gigalight:

Gigalight is a design innovator in global optical interconnect field. A series of optical interconnect products include: optical transceivers, passive optical components, active optical cables, GIGAC™ MTP/MPO cablings, cloud programmers & checkers, etc. Three applications are mainly covered: Data Center & Cloud Computing, MAN & Broadcast Video, and Wireless & 5G. Gigalight takes advantage of its exclusive design to provide clients with one-stop optical network devices and cost-effective products.