400G Transceivers

400G transceivers are commonly used solutions for 400G data center connections. There are several 400G transceiver form factors available, including QSFP-DD and OSFP. All of these transceivers differ in terms of transmission distance, connector, form type, and other characteristics.

400G Transceivers

The primary function of 400G transceivers in data centers is to increase bandwidth and port density. As data centers' bandwidth requirements grow, 400G optical modules will be the best way to improve system efficiency and lower bandwidth costs in the future.

400G DACs & AOCs

400G Direct Attached Cables (DACs) are a cost-effective solution for short-distance data center interconnections. DACs are typically divided into two types: passive copper cables for distances ranging from 0 to 5m and active copper cables (AOCs) for distances ranging from 5 to 15m.

400G DACs

As opposed to 400G DACs, 400G Active Optical Cables (AOCs) transmit data using fiber optical fibers, which is the same as using separate wires and transceivers. 400G AOCs permit transmission over longer distances than DACs and are limited to 100m. Although they cost more, they are more compact and lighter than DACs. AOCs are not impacted by electromagnetic interference, in contrast to DACs.

400G AOCs

There are two basic form factors for 400G DAC and 400G AOC: QSFP-DD and OSFP, both of which can transport 8x50G PAM4 electrical lanes. There are also 400G breakout DACs and AOCs with a single 400G connector on one end and many connectors with the same total rate on the other.

Both 400G DAC and AOC are economical options for short-distance transmission. 400G optical transceivers in conjunction with matching fiber optic cables are an appropriate solution for transmission over 100m.

400G ACC Cable

400G Active Copper Cable (ACC) refers to active copper cable, whose connection medium is the same as that of DAC. However, an active signal driver or equalizer chip is added inside the cable. These active chips can compensate for part of the loss caused by copper transmission, so they can transmit 2 to 3 times farther than DAC.

400G AEC Cable

400G Active Electrical Cable (AEC) is a specific type of active DAC. It contains a silicon chip inside the cable assembly, reconditioning the critical high-speed signals. The re-timers can clean, remove noise, and amplify the signal at the beginning and end of the transfer, ensuring high-speed transmission over longer distances.

How to Choose 400G DAC, AOC, ACC and AEC?

In the 400G high-speed connection solution, if there is a need for long-distance transmission and high performance requirements, AOC is preferred because it is easy to wire and is not susceptible to electromagnetic interference.

If customers have requirements regarding price, power consumption, etc., and do not need long-distance wiring, 400G DAC is undoubtedly the most economical choice.

Compared with 400G DAC, 400G ACC provides longer transmission distance and less transmission loss. In addition, they are more affordable and consume less power than 400G AOC.

400G AEC is more suitable for cabinet connections and distributed frame DDC. It has a smaller footprint, saving up to 70% of wiring space compared to 400G DAC. Moreover, it offers cost and power consumption advantages over 400G AOC.

Customers can choose the connection solution that best suits their needs based on their specific needs, weighing factors such as transmission distance, power consumption, cost, application scenarios, etc.