100G DWDM QSFP28: the latest 100G transceiver in 2022

At present, in the field of optical communication, almost all 100G switch interfaces are QSFP28 interfaces. In order to realize multi-channel 100G long-distance point-to-point dual fiber transmission, it must be applied to the transmission scheme of 100G DWDM. The coherent 100G DWDM transmission system is a new application for metro networks and a better solution for high-speed and high-capacity transmission.

The application of communication technology and the explosive growth of cloud data traffic put forward higher transmission performance requirements for the physical layer as the basis of the whole communication system, promote the development of coherent optical communication, and further improve the effect of total communication capacity and transmission distance on the basis of the original WDM system.

The 100G coherent DWDM enables customers to expand or upgrade existing 10G/40G networks to 100G applications without changing the original infrastructure, so as to achieve higher bandwidth and spectrum utilization.

100G DWDM QSFP28 vs 100G CFP/CFP2 Coherent solution

In the traditional application scheme of 100G DWDM, the 100G DWDM optical modules are mainly packaged in CFP or CFP2, and the switch interfaces are QSFP28. In order to realize inter-connection, the technology of active equipment 100G QSFP28 to 100G CFP/CFP2 is required, as shown in the following figure:

However, the traditional CFP/CFP2 coherent optical transmission mode, whether using active 100G QSFP28 to 100G CFP/CFP2 equipment or 100G CFP/CFP2 coherent optical module, has serious technical barriers, resulting in high price and cost. Coupled with the impact of COVID-19 in the past 2 years, the global optical chips are out of stock, and prices are rising, resulting in higher and higher costs of optical modules and even shortages.

Therefore, in order to cope with the market dilemma, FiberMall launched the optical module packaged with 100G DWDM QSFP28, which can be directly inserted into the QSFP28 interface of the 100G switch, and then cooperate with the scheme of dispersion compensation DCM and DWDM fiber amplifier (EDFA), which can replace the traditional transmission scheme of 100G CFP/CFP2 coherent light.

100G DWDM QSFP28 Solutions:

· Passive DWDM MUX 1X100G QSFP28 DWDM 120KM Solution

· Passive DWDM MUX 4X100G QSFP28 DWDM 80KM Solution

· Passive DWDM MUX 24X100G QSFP28 DWDM 80KM Solution

· Passive DWDM MUX 48X100G QSFP28 DWDM 80KM Solution

100G DWDM QSFP28 optical transceiver overview

The 100G DWDM QSFP28 dual-carrier transceiver is a hot-pluggable QSFP28 MSA form factor that can transmit up to 80km over SMF(single-mode fiber). It uses PAM4 modulation format on 100GHz ITU DWDM wavelength grid compatibility. The manufacture of the 100G DWDM QSFP28 transceiver is based on a highly integrated silicon photonic chip.

100G DWDM QSFP28 schematic diagram

The 100G QSFP28 DWDM optical module uses a non-adjacent dual-carrier wave optical transceiver. Its optical transceiver adopts a DWDM EML laser and PIN/APD detector made by FiberMall, combined with a self-made cyclic array waveguide grating (AWG) multiplexer, which can realize channel interval 50GHz DWDM transmission, support the working range of commercial temperature (0 ~ 70 ℃), and the typical power consumption is 5W.

The performance has reached the leading level in the industry, and combined with FiberMall’s optical amplifier and adaptive dispersion compensation module, it can realize point-to-point transmission of more than 100km. At the same time, the solution can be extended to non-adjacent four carrier optical modules of 200GE and higher versions. At present, FiberMall has formed 25G, 50G, and 100G color light series optical module solutions.

The introduction of a 100G QSFP28 DWDM transceiver to the market is a significant step forward in overcoming the difficulties of DWDM networking in their equipment. Customers who want to build an embedded DWDM network can use this transceiver directly in the switch. It’s a very simple and cost-effective solution.

However, there’s one small fact that you should consider if you’re going to apply the 100G DWDM optical network – it needs amplification to get out of the blocks and dispersion compensation to go beyond 5-6km. A separate DWDM multiplexer with an amplification system and dispersion compensation is therefore required to connect data centers together.

Final words

In today’s data interconnects, the 100G DWDM QSFP28 has been a trending product in recent months for network operators. The PAM4 technology is quite a capable option for extending 100G signals.

To summarize, FiberMall’s 100G DWDM QSFP28 is designed for data centers to interconnect applications that require high fiber capacity for links up to 80km. The optical interface utilizes two DWDM wavelengths on a 50GHz grid. The PAM4 modulation format is used to increase capacity enabling 50Gb/s on each wavelength. And finally, there’s another thing that should be noted is that you need to apply optical amplifiers to realize the 100G DWDM solution.