AOC Uses in Modern Data Centers

AOC is composed of integrated optoelectronic devices for high-speed, high-reliability interconnected transmission device between data centers, high-performance computers, and large-capacity memory devices. It usually meets the industry standard electrical interface and transmits data by the superiority of fiber optic cable and electrical-to-optical conversion.

While AOC reaches can extend to the limits of the optical technology used (100-200m), installing a long 100m cable, complete with an expensive transceiver end, is difficult in crowded data center racks so the average reach typically used is between 3-30m. Only one “oops” per cable allowed. Damaging the cable means replacing it as it cannot be repaired in the field. AOCs are typically deployed in open access areas such as within racks or in open cable trays for this reason.

Gigalight 25G SFP28 Active Optical Cables (AOCs) are direct-attach fiber assemblies with SFP28 connectors, compliant with 25G Ethernet IEEE 802.3by 25GBASE-SR standard. They are suitable for short distances and offer a cost-effective solution to connect within racks and across adjacent racks. The length is up to 70 meters using OM3 MMF and 100 meters using OM4 MMF.

The Advantages of Gigalight 25G SFP28 AOC

Low power consumption <1W

The pre-FEC bit error ratio (BER) is guaranteed to meet E10-8 25.78125Gb/s@PRBS31, 55℃, Better than the IEEE pre-FEC BER of less than 5 E-5.

Mature COB technology

Low Cost

High capacity, timely delivery

CE, UL, RoHS, GR-468 test report

Conclusion

The power and cost savings caught the eye of the Ethernet hyperscale and enterprise data center builders and has since become a popular way to link Top-of-Rack switches upwards to aggregation layer switches such as End-of-Row and leaf switches. Several hyperscale companies have publicly stated their preferred use of AOCs for linking Top-of-Rack switches. Additionally, single channel (SFP) AOCs have become very popular in high-speed, NVMe storage subsystems. Some hyperscale builders often run 10G or 25G AOCs from a Top-of-Rack switch to subsystems at reaches greater than DAC limits of 3-7m.

25G Low-Cost AOC

25G Ethernet, or 25Gigabit Ethernet (25GbE), is developed by IEEE 802.3 Task Force P802.3by. The IEEE 802.3by standard uses technology defined for 100Gigabit Ethernet implemented as four 25Gbps lanes (IEEE 802.3bj). Actually, 40G and 100G have already existed before the emergence of 25G. However, 25G Ethernet can provide a more convenient path to Ethernet speeds of 50G, 100G and beyond. With 25G, network operators are no longer to use 40G Ethernet (using four lanes of 10G) to migrate to 100G but using 4 lanes of 25G. The article introduces low-cost 25G AOC.

What Is A 25G AOC?

25G AOC can be overcome the bandwidth limitation of traditional high-speed cable, and the 25G AOC can provide an ideal alternative solution for high-speed cable and short-distance SFP28 optical transceiver, and the signal is more complete and higher performance. It is widely used in high-speed, high-density, and low-power data center networks.

The 25G AOC consists of optical transceiver devices at both ends and composed of different length of OM3 or OM4 multimode optical fibers. The transceiver devices at both ends can provide the function of photoelectric conversion and optical transmission. This function ensures data transmission stability and application flexibility.

The 25G SFP28 AOC is designed to operate over multimode fiber systems using a nominal wavelength of 850nm. The electrical interface uses a 20-contact edge type connector.

Features of Gigalight 25G SFP28 AOCs

● Hot-pluggable SFP28 form-factor connectors

● Transmission data rate up to 25.78Gbps

● 850nm VCSEL laser

● PIN photo-detector

● Internal CDR circuits on both receiver and transmitter channels

● Low power consumption < 1W per end

● Length up to 70m using OM3 MMF and 100m using OM4 MMF

● Operating case temperature range 0°C to +70°C

● 3.3V power supply voltage

● RoHS-6 compliant (lead-free)

Why Choosing Gigalight 25G SFP28 AOCs?

The Gigalight 25G SFP28 AOCs are direct-attach fiber assemblies with SFP28 connectors, compliant with 25G Ethernet IEEE 802.3by 25GBASE-SR standard. They are suitable for short distances and offer a cost-effective solution to connect within racks and across adjacent racks. The length is up to 70 meters using OM3 MMF and 100 meters using OM4 MMF.

Conclusion

Gigalight offers 25G SFP28 AOC to enable short reach options, as well as a range of optical transceivers in an SFP form factor for various fiber types and reach requirements.

A Widely Recognized Innovator That Meets Tomorrow’s Demands

It is crucial that the ability of continuous innovation is the source of sustainable development for a company. Gigalight is able to provide cost-effective products keeping up the times for customers. Gigalight designs products that meet the increasing demands for network bandwidth, data storage and so on. As an innovator in optical communication, Gigalight delivers specialist service, dependability and performance at competitive prices.

Gigalight has founded in 2006, is headquartered in Shenzhen, China. We have opened the Wuhan R&D Center in 2017. And we have representative offices in Russia, Taiwan. North America, Europe and India centers are in preparation. We cooperate with key channel distribution partners around the world.

We mainly focus on Internet operators such as Baidu, Alibaba, China Unicom, China Telecom and other traditional operators as well as data communications equipment manufacturers in China. Our overseas markets center on telecommunication, Internet operators and equipment suppliers in North America, Russia, Brazil, Israel, India, etc.

Our Innovation Road

In 2006–2009, Gigalight was committed to the R&D and production of optical components (from 100Mb to 10Gb/s) and built the global channel market of optical transceivers.

In 2010–2011, Gigalight launched 10G/40G/120G active optical cables for data center and high-performance computing applications.

In 2012–2013, Gigalight entered the passive optical components market and HD video communication market.

In 2014–2015, Gigalight completed the commercialization of its 10G/40G active optical cables in the data center.

In 2016–2017, Gigalight began to offer 25G/100G optical modules and active optical cables to customers worldwide.

In 2018, Gigalight was committed to large-scale production of 100G optical transceivers and accelerates the development of 200G/400G data center optics, coherent optics, 5G optical transceivers and 5G custom passive optical components.

In 2019, Gigalight is committed to developing 5G and the Next–Generation Data Center optical interconnection market.

At present, we obtained 5 items software copyright, invention patent more than 10 items and national patent total more than 100 items. The Gigalight R&D department has about 150 engineers which account for 25% of the company. And most of them are Master Degree or above.

Innovative Design Concept

Conciseness

Creative optical engine design

Creative automatic producing

Aesthetics

Updated ID design

Updated Layout design

Reliability

Complete FEMA design

Complete TR-468 qualified

Uniformity

Performance uniformity

Continue developing

Our Creations

Optics Micro Design

Reliability Design of Hardware

Uniformity Design

Visual Manufacturing and Cloud Design

Our Strengths

Gigalight will also continue developing its automatic production line, a creative production solution including Array Eutectic Soldering and a Passive coupling system, which it hopes will lead to a 200% increase in production capacity. These new processes should bring more products to the market in 2019.

Conclusion

Gigalight have achieved remarkable growth and wide recognition around the world based on the decade’s experiences.

At present, we have successfully developed 200G AOC and 400G AOC products based on PAM4 modulation technology. And we also developed mini TO platform with innovate design, which greatly reduced the cost for 40G/100G/200G SM products. The self-research project has made a great success in the automated production line. At the same time, a great breakthrough has been made in the coherent field, 100G CFP–DCO digital coherent optical transceiver with ultralow power consumption have been successfully developed. In 2019, Gigalight will commit to the next–generation data center, 5G and so on.

What Is 100G Digital Coherent Optical Receiver?

The backbone optical communication networks are an essential infrastructure supporting the networked society. They are used for the internet phone and video demand services and for business activities and public services and offices in order to provide more stress–free communication and better services.

Here introduce 100G technology a 100 gigabit per second digital coherent optical receiver which can be used to transmit 10 terabits per second of data over a single fiber.

What Is Digital Coherent Transmission Technology?

Let’s outline the history of the technical development that allows us to send a large capacity of information over an optical fiber before explaining this.

Time–Division Multiplexing

The first development was the use of time–division multiplexing. This made it possible for a single fiber to carry data at 10 gigabits per second.

Wavelength–Division Multiplexing

The next–generation was to adopt wavelength–division multiplexing by using 40 wavelengths each capable of 40 gigabits per second transmission it became possible to send 1.6 terabits per second of data over a single fiber.

Digital coherent Transmission

Now comes digital coherent transmission which is the most attention-grabbing technology today. This technology increases transmission capacity by using optical phase and polarization information the receiver extracts information by mixing the received light with a light from a local light source. Since a laser beam is normally polarized, it is possible to double the transmission capacity by using two orthogonal E polarized waves as different channels. In addition, instead of using binary values of on and off.

This technology makes use of four values of optical phase information thereby further doubling the transmission capacity. Consequently, the volume of information that can be carried is quadrupled.

We have implemented a system base on 28 to 32 gigabit per second transmission. We have doubled the transmission capacity by using phase information and further doubled it by using polarization information thereby achieving 100 gigabits per second transmission over a single wavelength by using about 100 wavelengths. It is possible to achieve 10 terabits per second transmission on a single optical fiber.

An optical receiver receives the phase and polarization information of digital coherent optical signals. It consists of three elements a passive optical circuit which is a silica base planar lightwave circuit or PLC a high–speed photodiode or PD array which is an optical semiconductor and a transimpedance amplifier which is a high–speed electronic device. This means that to implement a high-quality optical receiver. It is necessary to integrate silica-based PLC technology, optical semiconductor technology and high–speed electronic device technology.

Conclusion

Coherent optics provides the performance and flexibility to transport significantly more information on the same fiber. Coherent optical technology forms the foundation of the industry’s drive to achieve transport speeds of 100G and beyond, delivering terabits of information across a single optical fiber. And coherent optics enables greater network flexibility and programmability by supporting different baud rates and modulation formats. This results in greater flexibility in line rates, with scalability from 100G to 400G and beyond per single signal carrier, delivering increased data throughput at a lower cost per bit.

Gigalight 100G CFP-DCO Digital Coherent Optical Transceiver is a hot-pluggable CFP form-factor optical module designed for high-speed optical networking applications including 100-Gigabit Ethernet and OTU4. The CAUI and OTL4.10 electrical interface and MDIO management interface are built in the module.

The 100G CFP-DCO module converts 10-lane 10Gb/s electrical data streams to 128G DP-QPSK optical output signal in Egress and also converts DP-QPSK optical input signals to 10-lane 10Gb/s electrical data streams in ingress. This 10-lane 10Gb/s electrical signal is fully compliant with 802.3ba CAUI specification and OIF-CEI-03.1 specification and allows FR4 host PCB trace up to 25cm. Gigalight is committing to develop the 100G CFP-DCO module to provide innovative and cost-effective products for the customer.

What Is SFP?

SFP stands for Small Form-Factor Pluggable. It is a compact, hot-pluggable transceiver used for both telecom and datacom applications.

SFP module has two ports, one port has laser inside, which is the transmitter side. The other port has a photodetector inside, which is the receiver side. So basically, SFP is a transceiver module, since it has transmitter and receiver in a single unit.

Which Components Make Up the SFP Optical Module?

The SFP optical module is composed of laser, circuit board IC and external accessories. The external accessories include shell, unlocking part, buckle, base, gripper, rubber plug, PCBA, and the color of gripper can help you to identify the parameter type of the module. For the types of SFP module, there are many types for SFP module such as BIDI-SFP, Electrical interface SFP, CWDM SFP, DWDM SFP, SFP+ transceivers and so on. In addition, for the same type of XFP, X2, XENPAK optical transceivers, SFP optical transceivers can not only be directly connected with it, but also have the feature of lower cost than it.

How Are the SFP modules used on the PCB board?

The following picture shows a perspective view of the SFP module, so you can clearly see its mechanical outlines.

SFP

Gigalight 10G SFP+

SFP module’s mechanical interface and electrical interface are specified by a multi-source agreement, also called MSA.

MSA is an industrial group composed of many network component vendors, such as Finisar, Fujikura, Lucent, Molex, Tyco, etc.

Engineers from these major vendors came together and made a design that everybody agreed upon. So based on this MSA specification agreement, these companies can make products that can work together in a system without compatibility issues. It is almost like an industry standard.

SFP was designed based on the bigger GBIC interface, but SFP has a much smaller footprint in order to increase port density. That is why SFP is also called mini-GBIC.

SFP modules are classified based on the working wavelength and its distance reach. Let’s take a look at the list here.

For multimode fibers, the SFP module is called SX. SX modules use 850nm wavelength. The distance that the SX module supports depends on the network speed. For 1.25 Gbps, the reach is 550 meters. For 4.25 Gbps, SX modules support 150 meters.

For single mode fibers, there are a lot of choices. I am listing the most common types here.

LX modules use 1310nm wavelength laser and support up to 10km reach. ZX modules use 1550nm wavelength laser, and supports reach up to 80km. ZX modules also use 1550nm laser but support up to 120km reach.

There are also CWDM and DWDM SFP modules, which use multiple wavelengths in the module to support even more bandwidth and distance.

And don’t forget, the MSA also defined a SFP module based on the UTP twisted pair copper cables. But this SFP module currently only supports Gigabit Ethernet.

Traditional SFP modules support the speed up to 4.25 Gbps. But an enhanced version, which is called SFP+, supports up to 10Gbps, and is becoming more popular on 10Gigabit Ethernet and 8Gbit Fibre Channel.

SFP transceivers are used on all types of network applications, including telecommunication, data communication, Storage Area Network.

On the protocol side, there are SFP modules that support SONET/SDH, Gigabit Ethernet, Fibre Channel, Optical Supervisory Channel, and more.

Conclusion

Gigalight is committing to providing cost-effective products for customers. 10G optical modules such as 10G SFP+, 10G CWDM SFP+, 10G DWDM SFP+ can be provided by Gigalight. Gigalight has been investing in the development of colored (CWDM/DWDM) transceivers which have been widely sold around the world. You can find more relevant information from Gigalight‘s official website.

How to Choose the Right 200G Optical Transceiver Supplier in China for Your Network Upgrade?

Some network operators choose 200G instead of 400G to address rapid datacenter traffic growth. For example, according to LightCounting reports that Facebook will deploy 200GbE before 400GbE, while Google already has begun 2x200GbE optical transceiver. 200G optical transceiver is expected to find acceptance in parts of the cloud and enterprise data center networking space at the same time frame as 400G.

As we all know, there are just a few suppliers to provide 200G optical transceiver, so it is vital to choose the right supplier for network operators.

Since most companies are unaware of how to choose the right supplier so that they missed the chance to cooperate with the right partner. Here are some ways that will help you verify their effectiveness for your needs.

Google Search Engine

You can affirm the credibility of the optical transceiver supplier by checking the information of 200G optical transceivers. Simply input words such as “200G optical transceiver” or “200G QSFP-DD” onto the Google search engine to see.

Form Factor

There are several 200G form factor such as QSFP-DD, QSFP 56, CFP2. The QSFP-DD form factor addresses the need for high-density, high-speed networking solutions in a module host that’s backwards compatible with QSFP28 and QSFP56.

The QSFP56 is a form factor supporting 200G data rates. This module has the same mechanical design and electrical connector as a QSFP28 but provides a four-lane electrical interface running at 50G PAM4 per channel, instead of 25G NRZ.

The industry standard pluggable CFP2 form factor was designed in accordance with the Implementation Agreement defined by the Optical Internetworking Forum. The CFP2-ACO form factor offers an optics-only solution for customers who currently rely on in-house DSP capabilities. The 200G CFP2-DCO optical transceiver mechanical outline is the standard CFP2 MSA size (106 mm x 41.5 mm x 12.4 mm). Electrical interfaces are provided through the 104-pin connector and optical interfaces through two LC optical receptacle connectors.

Applications

The 200G QSFP-DD optical transceivers are mainly used in hyperscale cloud data centers.

The 200G QSFP56 optical transceivers for applications in hyperscale cloud data centers that require 200G optical connectivity.

The 200G CFP2-ACO optical transceivers are commonly used in the metro carrier and DCI applications where high density and pluggability are more valued.

The 200G CFP2-DCO optical transceivers are a CFP2 MSA-compliant digital coherent optical module designed for line-side trunk DWDM data center interconnect (DCI), metro carrier, and regional/long haul applications.

Services

A good optical transceiver supplier can provide flexible services. Every individual company is different and can provide different services for customers. A high–effective company will be easily contacted by customers and communicate clearly. You can contact us through various channels such as the official website or Facebook, Linkedin and so on.

Conclusion

As an intermediate step between 100G and 400G, 200G optical connectivity is a compelling solution for Cloud Data Centers challenged to implement faster optical links at scalable volumes and costs. DSPs will undoubtedly play a pivotal role on the path to 400G, and in the interim, the fully analog 200G optical transceiver architecture lights the path to faster, cost-effective connectivity beyond 100G.

The 200G optical transceivers from Gigalight were able to meet the demand of customer cost-effectively deploy 200G networks.

3GPP 5G Standards

The 5G standardization process is complex and highly innovative. 5G standards are developed in the 3rd Generation Partnership Project (3GPP), ITU Radiocommunication Sector (ITU-R), ITU Telecommunication Standardization Sector (ITU- T), the Internet Engineering Task Force (IETF) and IEEE. Here we focus on activities within 3GPP.

1.3GPP 5G will expand the LTE platform for new services while improving its efficiency to meet the mobile broadband demand.

2.3GPP 5G is not only a new radio (NR) interface but a full system, integrating LTE and NR radio access technologies with a 5G Core Network

Initially, some of the use cases will be fulfilled by LTE, but the aim is to eventually fulfill all the requirements with NR
From Release 15 onwards, the 3GPP specifications (LTE, NR and Core Network) will be marked “5G”

5.5G expands offerings by specializing radio and network capabilities (vertical sectors):

– Enhanced Mobile Broadband

– Massive Internet of Things

– Ultra-Reliable & Low Latency

Recent 3GPP 5G Developments

In September 2017 3GPP RAN plenary re-enforced the timeline commitment for 5G development set out in March 2017.
The focus for the “early drop” (December 2017) – Focus on LTE-anchored LTE-NR Dual Connectivity (DC) – Nonstandalone (NSA) NR – Several functions moved beyond December 2017
Focus for the full Release 15 in June 2018: Standalone (SA)NR with new 5G Core

–NSA and SA share common 5G NR physical layer specifications for the air interface, and, thus, these aspects were covered in the December 2017 milestone.

–The main focus for the SA standardization is on the upper layers with full user and control plane capability and on the next-generation core network architecture, including network slicing.

According to the plan of 3GPP, 5G standards are divided into NSA (Non-Standalone) and SA (Standalone). Among them, the Non-Standalone, which is to say the 5G networks will be supported by existing 4G infrastructure.

5G SA and NSA Standard

The 5G SA Standard

More than 600 delegates from the world’s major telecom operators, network, terminals and chipset vendors, internet companies and other vertical industry companies have witnessed this historic moment for 5G.

As the Release 15 work has matured and drawn close to completion, the group’s focus is now shifting on to the first stage of Release 16, often referred to informally as ‘5G Phase 2’. Among them, R15 mainly meets the application needs of Enhanced mobile broadband (eMBB) and Ultra-Reliable Low-Latency Communication (URLLC). This stage is divided into two sub-stages. The first sub-stage 5G NR (New Radio) NSA feature was completed in December 2017 and frozen in March 2018. The second sub-phase, 5G NR standard, was completed in June 2018 and frozen in September.

The formulation of 5G NR standard means that the deployment standard of the whole 5G network has been improved, which will lead the industry to realize the commercialization of 5G communication and serve as the core infrastructure for the fourth industrial revolution in the future. As the first phase of 5G international standard, R15 can realize all the new features of 5G, which is conducive to giving full play to the full capacity of 5G. It is a truly commercially-oriented 5G standard and has some synergies with the final version of 5G R16 standard.

The 5G NSA Standard

Previously, in order to support national and national operators to achieve pre-commercialization of 5G in 2019, 3GPP completed 5G NSA standard ahead of schedule in December 2017 to support operators to carry out 5G mobile broadband business on the basis of the existing 4G core network. The released SA standard completes the 5G core network architecture and realizes 5G independent networking. SA standard can achieve the characteristics of 5G such as high reliability, ultra-low time delay and high efficiency, which is the core attribute of 5G to penetrate into the medical, industrial Internet, Internet of vehicles and other industries.

Conclusion

5G is a key milestone in the history of optical communication. For 5G optical networks, there is a huge market with so many challenges. Gigalight will keep providing customers with high-speed optical interconnection products with innovative designs and leading solutions.

Gigalight has launched a series of industrial-grade optical transceivers such as 25G BiDi SFP28 LR, 25G CWDM SFP28 LR，25G DWDM SFP28 optical transceivers for 10km/20km applications in the 5G fronthaul network, and 100GBASE-LR4/4WDM-40 QSFP28 modules along with 200G QSFP56 LR4 used for 10km applications in 5G midhaul (and backhaul) network. At the same time, we also offer industrial-grade passive optical components such as 5G OMUX, CCWDM, and AAWG.

The Path to Upgrade Data Center

With the increasing demand for high bandwidth from private cloud, public cloud data center and service providers, 25G and 100G are widely used. 200G and 400G optical devices will be successively produced and shipped from 2019. So far, most server vendors have started offering servers 25G of fiber-optic network CARDS as an I/O(input/output) option, and Ethernet’s signal transmission rate has increased from the earlier 10G to 25G, 100G or higher. While 1G, 10G and 40G currently dominate the Ethernet port market, the future demand for 25G and 100G is stronger than ever as high bandwidth is undeniably driving data centers toward greater scalability and flexibility.

Why Is 25G Coming to Data Centers?

Data centers are expanding at an unprecedented rate, driving the need for higher bandwidth connections between servers and switches. To accommodate this trend, the access network has been upgraded from 10G to 25G, providing high-density, low-cost, and low-power solutions for the connection between servers and ToR switches.

The Development History of 25G

Since its advent in 2014, Google, Microsoft, Arista Networks, Broadcom, and Mellanox have been driving the development of the 25G Ethernet standard, which is intended to enable a 25G top-shelf server network. With the increasing popularity of 25G and its rapid spread in the market, 25G will provide a comprehensive solution for the connection between server and switch in the future.

The Advantages of 25G

Before the release of 25G Ethernet standard, enterprises, operators and other data centers generally adopt the network upgrading method of 10G to 40G. With the official release of 25G Ethernet standard, 25G to 100G network upgrading method has gained more applications with the advantages of low cost, low power consumption and high density, promoting the rapid development of 100G Ethernet. Let’s take a look at the differences between 10G, 25G, 40G, and which upgrade is superior.

25G Can Provide Higher Performance Bandwidth Than 10G

In the current data center, the network connection between the server and the switch is generally between 10G and 25G. Compared with 10G, 25G is an improvement based on 10G packaging and chip technology, providing higher bandwidth and performance. The emergence of 25G enables the data center to be based on the existing network architecture without any cable interconnection, and can also support the transmission of higher rate (over 10G), meet the demand for higher bandwidth in the future network, and make the network upgrade more convenient and easy. The wiring infrastructure required for 25G and 10G transmission is basically the same, which can effectively avoid the expensive cost and the complexity of rewiring and make the network upgrade more convenient.

In addition, the 25G is similar to the 10G in that it uses a single channel of SerDes for backward compatibility, significantly reducing power consumption and costs and helping data center operators save capital and operating expenses.

Insert 25G SFP28 optical transceiver into 10G SFP+ port, what speed will we get?

Theoretically, the 25G SFP28 optical transceiver is backwards compatible with 10G SFP+ port, and its rate can reach 10G/s. However, this mode of use is not suitable for all brands of switches and optical transceivers. Considering the limitation of the fiber network card and switch port, this mode is generally not recommended.

25G Is More Suitable for High-density Requirements Than 40G

For large, high-end enterprises, the port density of the server largely determines the cost of cabling and switch infrastructure in the whole system. Therefore, compared with 40G, the cost of upgrading from 25G to 100G is relatively low. Because 25G to 100G network upgrade, the switch port is fully utilized, effectively reducing the cost of bandwidth.

It has been upgraded to a 40G network. Is it necessary to deploy a 25G network?

25G devices are expensive compared to 40G devices, so having upgraded to a 40G network, is it necessary to deploy a 25G network? Due to the cost rationalization of the 25G channel, 25G is definitely an important path to upgrade from 10G to 100G or higher in the future. If you need to increase the baud rate (signal transfer rate) or plan to upgrade the network to a higher speed (100G/200G/400G), then you must deploy the 25G network. If there is no requirement, then you do not need to deploy the 25G network.

The Prospect of 25G

At present, 25G servers and 100G switches can be seen everywhere in very large data centers. They gradually replace the earlier 10G servers and 40G switches. This network upgrade increases the throughput of the whole system by 2.5 times and reduces the incremental cost of equipment. As the Ethernet industry continues to innovate and lay the foundation for higher rate research and development, the 25G-100G upgrade model has become an important path for data centers.

25G Offers More Possibilities for 50G

As we all know, 25G can provide 2.5 times the bandwidth compared with 10G, and 50G can provide 1.25 times the bandwidth compared with 40G in the future. Currently, 50G has been proposed as the basis for 100G,200G, 400G network upgrade, but the implementation of 50G Ethernet standard still needs some time.

25G will provide more possibilities for 50G, as the implementation of 50G Ethernet can be based on two 25G channels, so it will be an alternative to the current use of four 10G channels up to 40G, reducing the cost of network equipment in the data center by reducing channel deflection. In the future, the network upgrade path may evolve from the traditional 10G-40G-100G to 10G-25G-50G-100G. In any case, upgrading a data center from multiple 25G channels to a 50G or 100G network will be simpler and more economical.

25G Lays the Foundation for 200G and 400G Network Upgrade

The 25G,50G,100G network architecture offers greater flexibility and is often used as a solution for large data centers, paving the way for later 200G/400G upgrades. At present, high-end enterprises and large data centers are shifting towards this, effectively promoting the implementation of large data centers and the interconnection between data centers. Nowadays, more and more suppliers in the market are engaged in the research and development of 200G and 400G optical devices, some of which have been successfully put into use. The implementation of 100G Ethernet is based on the development of 25G/50G. Similarly, the future network upgrade of 200G and 400G will be based on 100G. The following table lists the paths from 25G/50G/100G to 200G/400G.

Conclusion

The need for higher speed and performance in future data centers will never cease. Looking back at the evolution of 25G over the past few years, you can see that the emergence of 25G is a milestone in the next generation of data center network bandwidth and channel capacity expansion. The 25G to 100G network upgrade overturns the traditional 10G-40G network and improves the efficiency of the data center by providing higher bandwidth and port density, reducing power consumption and cost. It lays a solid foundation for the 200G/400G upgrade. Let’s wait and see how the continuous development and innovation of Ethernet will promote the new round of changes in the data center.

Gigalight supplies one-stop data center optical transceivers for 40G/50G/100G/200G/400G Ethernet interconnections. Gigalight has been keeping pace with the industry’s mainstream technology, focusing on boutique development to help users create a high-capacity, high-reliability, large cache cloud data center network. In the future, Gigalight will bring more innovative products to customers.

Three Hot Selling 200G Optical Transceivers for Data Center

The dramatically grew in demand for 100G CWDM over the past year. While 100G continues to ramp, the promise of high volume 400G remains omnipresent, albeit a 2019 phenomenon. Customers need existing technologies that ship in production volumes to fill this industry gap. While 100G CWDM is a mature and well-understood technology and will continue to ramp in the coming year, many of the big Cloud Data Center OEMs are turning their sights to 200G, to meet the pressures of enabling faster connections at scale volumes.

200G optical transceivers with their many advantages such as significantly lower latency, power consumption and cost are coming to market now, and are seen by many as a viable, volume-scalable stepping-stone to 400G. The three hot selling 200G optical transceivers for the data center will be introduced in this article.

No. 1

200G QSFP-DD SR8 NRZ

QSFP-DD ports are backwards compatible with QSFP28 which is very important to provide a smooth upgrade path and links with older systems. The backwards compatibility of the QSFP-DD allows for easy adoption of the new module type and accelerate overall network migration.

Application

It is a high-performance module for short-range multi-lane data communication and interconnects.

The Gigalight 200G QSFP-DD SR8 NRZ optical transceiver is designed for 2×100-Gigabit Ethernet 100GBASE-SR4 applications. The 200G QSFP-DD SR8 optical transceiver is designed to operate over multimode fiber systems using a nominal wavelength of 850nm. This module incorporates Gigalight proven circuit and VCSEL technology to provide reliable long life, high performance, and consistent service. Historically VCSEL-MMF links have been seen by many as the lowest cost short-reach interconnect.

No. 2

200G QSFP-DD PSM8 NRZ

The form-factor for 200G QSFP-DD PSM8 NRZ optical transceivers are similar to 200G QSFP-DD SR8 NRZ.

Application

It is a high-performance module for data communication and interconnects.

The Gigalight 200G QSFP-DD PSM8 NRZ optical transceiver is designed for 2×100-Gigabit Ethernet PSM4 and InfiniBand DDR/EDR applications. The 200G QSFP-DD PSM8 (dual PSM4) module integrates eight data lanes in each direction. Each lane can operate at 25.78Gbps up to 2km/10km over G.652 SMF. It is designed to operate over single-mode fiber systems using a nominal wavelength of 1310nm. The electrical interface uses a 76-contact edge type connector. The optical interface uses a 24-fiber MTP/MPO connector. This module incorporates Gigalight proven circuit and optical technology to provide reliable long life, high performance, and consistent service.

No. 3

200G QSFP56 SR4 PAM4

PCB layout and heat dissipation design are crucial challenges for 200G QSFP56 SR4 PAM4. Too many components, smaller QSFP56 package and the larger thermal power consumption which are the main reasons.

200G QSFP56 optical transceiver represents an evolution of the highly popular four-lane QSFP+ form factor is ideally suited for hyperscale data centers and high-performance computing (HPC) environments.

Application

It is compliant with the QSFP MSA and IEEE 802.3cd 200GBASE-SR4 specification.

The Gigalight 200G QSFP56 SR4 PAM4 optical transceiver is designed for 200-Gigabit Ethernet links over multimode fiber. This transceiver is a high-performance module for short-range multi-lane data communication and interconnects. It integrates four data lanes in each direction with 212.5Gbps bandwidth. Each lane can operate at PAM4 53.125Gbps (26.5625GBd) up to 70m using OM3 fiber or 100m using OM4/OM5 fiber. These modules are designed to operate over multimode fiber systems using a nominal wavelength of 850nm. The electrical interface uses a 38-contact edge type connector. The optical interface uses a 12-fiber MTP/MPO connector. This module incorporates Gigalight proven circuit and VCSEL technology to provide reliable long life, high performance, and consistent service.

Conclusion

200G and even 400G transceivers will start to be commercially adopted starting 2019 and will start taking away the market share from the 100Gbps transceivers. 2019 will be a pivotal year to see how 200G takes hold in the cloud datacenter, and intensifying industry collaboration on 200G standards and interoperability could help position this technology for sustained mainstream adoption while 400G continues to mature.

Which One Is the Option for 5G Fronthaul? 10G, 25G or 100G?

5G is expected to be implemented in the following years. To have this 5G network realized, optical communication will be the cornerstone technology independent of various fronthaul options. The demand for high-rate optical transceivers will significantly increase because higher base-station density is required for the 5G network.

Although it is still not clearly determined which fronthaul architecture will be used in the 5G network, it is apparent that the network would employ both grey and color optics for 25Gbps based on 5G bandwidth requirement.

Grey and Color Optics

The light in WDM systems is carried over different wavelengths compliant with specific standards.

To distinguish wavelengths in different systems, the wavelengths in WDM systems are called colored light whereas the wavelengths in common optical systems are called grey light.

Grey light is within a certain wavelength range and does not have a standard wavelength, for example, the light at client-side optical ports of WDM devices.

Colored light is WDM-side optical signals of the OTN or line boards in a WDM system. The signals can be directly transmitted to multiplexer devices and have standard wavelengths.

Colored light is divided into CWDM and DWDM light, depending on wavelength division standards.

For 5G network, Gigalight has a complete portfolio of 10Gbps and 25Gbps optical transceivers that are tailored for upcoming standards such as eCPRI/NGFI as well as traditional CPRI options.

Gigalight 25G SFP28 transceivers also play in a critical role in the growing bandwidth demand in next generation access networks such as 5G wireless. While interface developments, like the recently released eCPRI specifications, will help improve bandwidth efficiency, the 5G wireless infrastructure will require significantly higher capacity in the optical links. Compact, power and cost-efficient 25G transceivers supporting both Ethernet and CPRI-10 while exposed to the elements will play a key role in supporting the rollout of this next generation wireless infrastructure.

Conclusion

At present, 10G optical transceivers were mainly used in LTE base stations. In the 5G network, it is expected that 25G and even 100G optical transceivers shall be the preferred solutions of the optical fronthaul network.