Types of 800G Optical Transceiver Modules

With the continuous surge in the demand for faster data transmission, 800G optical transceiver modules have garnered extensive attention for their high bandwidth, fast transmission rates, excellent performance, high density, and future scalability. In this article, we will provide an overview of various types of 800G optical transceiver modules to help you make better choices when selecting 800G optical transceiver modules.

800G=8x100G=4x200G. Therefore, based on single channel rate, 800G optical transceiver modules can be roughly divided into single-channel 100G and 200G categories. The following diagram shows the matching architectures. Single-channel 100G optical transceiver modules are relatively easier to achieve, whereas 200G optical transceiver modules demand higher requirements for optical devices, needing gearboxes for conversion. This article will primarily introduce single-channel 100G modules.

Single-Mode 800G Optical Transceiver Modules

800G single-mode optical transceiver modules are suitable for long-distance fiber transmission and can cover a broader network range.

800G DR8, 800G PSM8, and 800G 2xDR4

The internal architectures of these three standards are similar, all featuring 8 transmit and 8 receive channels, with a single-channel rate of 100Gbps, requiring 16 fibers.

• 800G DR8 optical transceiver modules use 100G PAM4 and 8-channel single-mode parallel technology with single-mode fiber, supporting transmission distances up to 500m. Typically used in data centers, 800G-800G, 800G-400G, and 800G-100G interconnects.

  
  

• 800G PSM8 optical transceiver modules use CWDM technology, having 8 optical channels, each transmitting at 100Gbps, supporting transmission distances up to 100m. They are ideal for long-distance transmission and fiber resource sharing.

  
  

• 800G 2DR4 refers to 2 "400G-DR4" interfaces. It comes with 2 MPO-12 connectors, requiring no fiber breakout cables. Each 800G optical transceiver module can achieve 2 physically distinct 400G-DR4 links. As shown in the diagram below, this optical transceiver module can connect to 400G DR4 optical transceiver modules, supporting transmission distances up to 500m, suitable for data center upgrades.

800G 2FR4/2LR4/FR4/FR8

In the names, 800G FR and LR stand for fixed range and long range, indicating fixed and longer transmission distances, respectively.

• 800G 2xFR4 and 800G 2xLR4 are two additional standards with similar internal structures. They consist of 4 wavelengths, operating at a single-channel rate of 100 Gbps. The  optical transceiver modules reduce the required number of fibers to 4 by using Mux, as shown in the diagram below. These standards are upgraded versions of 400G FR4 and LR4 optical transceiver modules. They use 1271/1291/1311/1331nm CWDM4 wavelengths. 800G 2xFR4 supports transmission distances of up to 2km, while 800G 2xLR4 supports transmission distances of up to 10km. The optical interfaces of these standards use dual CS or duplex LC connectors. They are suitable for 800G Ethernet, split 2x400G FR4/LR4, data centers, and cloud networks.

  
  

• 800G FR4 optical transceiver modules use 4 wavelengths, PAM4 technology, with a single-channel rate of 200Gbps, and need 2 fibers, as shown in the diagram below. The module supports transmission distances up to 2km and is generally used for data center interconnects, high-performance computing, and storage networks.

• Lastly, 800G FR8 optical transceiver modules use 8 wavelengths, each operating at 100Gbps, as shown in the diagram below. The module requires two fibers, supporting transmission distances up to 2km. Additionally, 800G FR8 can provide higher transmission capacity and is commonly used in wide area networks, data center interconnects, and more.

Multi-mode 800G Optical Transceiver Modules

When transmission distances are less than 100m, two main standards exist for multi-mode 800G optical transceiver modules applications.

800G SR8

800G SR8 optical transceiver modules use VCSEL technology, with a wavelength of 850nm, and a single-channel rate of 100Gbps PAM4. It requires 16 fibers. This can be viewed as an enhanced version of 400G SR4 with twice the number of channels. The optical transceiver module uses MPO16 or dual MPO-12 optical interface, as shown in the figure below. 800G SR8 optical transceiver module is usually used for 800G Ethernet, data center link or 800G-800G interconnection.

800G SR4.2

This solution uses two wavelengths, 850nm and 910nm, to achieve single-fiber bidirectional transmission, commonly known as bidirectional transmission. The module contains a DeMux component to separate the two wavelengths. The single-channel rate is 100Gbps PAM4, requiring a total of 8 optical fibers, which is half the number of optical fibers required for SR8.