Introducing 800G Ethernet: A Brief Overview - NADDOD Blog

Introducing 800G Ethernet: A Brief Overview

NADDOD Brandon InfiniBand Technical Support Engineer Jan 26, 2024

1. What is 800G Ethernet?

800G Ethernet is a high-bandwidth Ethernet standard that can transmit data at a rate of 800Gbps (gigabits per second). It represents the latest advancement in Ethernet technology, aiming to meet the increasing demands for data transmission and processing.

 

The 25G and 50G Ethernet Alliance standards provide technical specifications based on eight 100Gb/s lanes, enabling the adoption of advanced high-bandwidth Ethernet technology.

 

800G Ethernet is primarily used in large-scale data centers, cloud service environments, and applications that require high bandwidth. It offers higher speeds, greater throughput, and improved network performance, supporting faster and more efficient data communication.

 

2. 800G Ethernet Architecture

 

The 800Gb/s Ethernet technology is designed as an interface that utilizes eight 106Gb/s channels, connected with a 2xClause 119 PCS (400G) to operate at 800Gb/s with a single MAC (although the 400G PCS has been modified, this is just a high-level conceptual view). The following diagram illustrates the high-level architecture.

 

800g Architecture

In the specific implementation process, the 800GBASE-R specification is not simply the concatenation of two 400G connections. Instead, it introduces new Medium Access Control (MAC) and Physical Coding Sublayer (PCS) to achieve 800G with minimal cost. The new PCS, which includes reuse of the previous PCS, retains the standard RS (544, 514) forward error correction and provides excellent backward compatibility features.

 

PCS/FEC

 

The capability to support 800Gb/s is achieved by utilizing two 400Gb/s PCS (including FEC) and supporting 32 PCS lanes (each lane operating at 25Gb/s). The following diagram illustrates the TX PCS data flow and functionality. The two PCS stacks generate 2x16 PCS lanes, which are then multiplexed by the PMA to the PMD in a 4:1 bit multiplexing scheme, creating 8x106G PMD lanes.

 

TX PCS data flow and functionality

The following diagram, provided by the 800G Pluggable MSA Working Group in the "800G MSA White Paper," presents a conceptual illustration of a fast-to-market 800G implementation. It involves reconfiguring two 400G PMAs to obtain an 800G PMA, defining a cost-effective 800G PMD, and ultimately achieving 800G Ethernet based on 8x100Gb/s channel technology.

 

800G Ethernet based on 8-channel 100Gbs

3. 800G Ethernet challenges and solutions

In the process of promoting and adopting 800G Ethernet technology, there are several challenges to consider, including:

 

  1. High complexity: Implementing 800G Ethernet involves higher data rates and more complex technical requirements. Designing and developing hardware and software solutions that meet these requirements require in-depth expertise and technical knowledge.

 

  1. Signal integrity: As data rates increase, signal integrity becomes critical. High-speed signals are susceptible to noise, attenuation, and crosstalk during transmission, requiring advanced signal conditioning and equalization techniques to maintain signal stability and accuracy.

 

  1. Power consumption and heat dissipation: The high data rates of 800G Ethernet require more power to drive and process the signals. This can lead to power consumption and heat dissipation issues, especially in high-density data centers and network devices. Therefore, energy efficiency and heat management become crucial considerations.

 

  1. Compatibility and interoperability: Ensuring compatibility and interoperability with existing Ethernet standards and devices is essential during the transition to 800G Ethernet. This involves ensuring interconnectivity between protocols, interfaces, and devices to ensure smooth network migration and interoperability.

 

  1. Cost-effectiveness: The cost of deploying 800G Ethernet technology is a significant consideration. High-speed hardware and equipment may come at a higher cost, and additional investments may be required during implementation and maintenance. Therefore, finding cost-effective solutions for sustainable deployment of 800G Ethernet becomes crucial.

 

BIT

To address these challenges, the following solutions can be implemented:

 

  1. Technological research and innovation: Continuously engage in research and innovation to address the challenges of high complexity and signal integrity. This includes developing advanced signal conditioning and equalization techniques, improving circuit design and layout to enhance signal stability and accuracy.

 

  1. Power optimization design: Adopt power-optimized design methods to reduce the power consumption of key components such as SerDes in 800G Ethernet. This includes using advanced CMOS processes and low-power circuit design techniques, such as low-power transistors, voltage regulation, and power management technologies.

 

  1. Heat management: Implement effective heat management strategies, particularly in high-density data centers and network devices. This can involve using advanced cooling techniques, optimizing hardware layout and ventilation design to ensure stable operation of equipment at high data rates.

 

  1. Standardization and interoperability: Ensuring compatibility and interoperability with existing Ethernet standards and devices is critical in driving the adoption and deployment of 800G Ethernet. Participate in standardization organizations and contribute to the development of unified protocol and interface standards to facilitate interoperability among devices.

 

  1. Cost-effective solutions: When considering cost-effectiveness, finding economically efficient solutions is crucial. This may involve devising reasonable procurement strategies, seeking cost-effective hardware suppliers, and considering the lifecycle costs of equipment.

 

By implementing these solutions collectively, the promotion and deployment of 800G Ethernet can be facilitated, overcoming the challenges involved. Additionally, industry collaboration and knowledge sharing are vital for driving the development of 800G Ethernet.

 

4. 800G Ethernet Products

The existing Ethernet technology is currently deploying 400G on a large scale, and there is still a long way to go before reaching the data rate of 800G. However, Ethernet transmission technology is continuously evolving and innovating. 800G multimode optical modules/AOCs/DACs are expected to continue leading the development in the networking field, providing strong support for the network requirements of the digital era. As a professional module manufacturer, NADDOD produces optical modules ranging from 1G to 800G. We welcome everyone to learn about and purchase our products.

NADDOD 400G QSFP-DD SR4 Module