Since 2015, the Ethernet Alliance has consistently updated its roadmaps to deliver clear and comprehensive overviews of Ethernet technology developments. These updates serve as valuable resources for professionals in various industries, helping them stay informed about emerging trends and innovations in Ethernet technology.
The following newly released 2024 Ethernet roadmap outlines the evolving Ethernet speed requirements in key sectors, including building and industrial automation, in-vehicle networking, enterprise and campus applications, telecommunications and mobile services, and hyperscale data centers. A significant update in the 2024 roadmap is the introduction of a dedicated section focused on AI and machine learning. This new section places AI at the core of Ethernet technology advancements, underlining its growing influence on the future development of Ethernet standards.

Source：https://ethernetalliance.org


Source：https://ethernetalliance.org

The above "2024 Ethernet Roadmap" introduces updated interfaces and nomenclature, classifying transmission media into two primary types: copper cables and fiber optics, with WiFi excluded. This classification provides a clearer framework for understanding Ethernet's evolving role in modern networking technologies. 
In Ethernet applications ranging from 10M to 10G, copper cables continue to be the preferred solution. These cables are widely adopted due to their ability to connect a large number of network devices, making them ideal for handling numerous connection points. Copper cables typically have shorter transmission distances, usually within 100 meters, though the 10Base-T1L standard supports low-speed 10M applications with a longer reach of up to 1000 meters.

A significant advantage of copper cables is their support for Power over Ethernet (PoE). This feature allows copper cables to deliver both data and electrical power to connected devices simultaneously, making them highly practical and cost-effective. This capability is especially useful in environments where both data transmission and power supply are required for devices like IP cameras, access points, and phones. 
In conclusion, Copper cable interfaces offer a low-cost, high-performance solution for Ethernet connectivity. 
In Ethernet applications above 10G, especially for ultra-high-speed network connections such as 40G, 100G, 400G, and even 800G and 1.6T, only fiber optics can meet the demands. For data center applications within 300 meters, multimode fiber provides an ideal balance of cost and performance. However, for longer-distance fiber transmissions, only single-mode fiber can deliver the necessary range and stability for reliable data transfer across extended distances.
Multimode fiber typically uses an MPO connector with multi-core parallel transmission, making it well-suited for high-density applications. And single-mode fiber often utilizes a dual-core LC connector with wavelength division multiplexing (WDM) technology for transmission, allowing it to efficiently support long-distance data transfer. (Note: This discussion does not include single-core bidirectional or triple-path transmission technologies found in PON systems.)

According to the 2024 Ethernet Roadmap and the latest interface and nomenclature guides, 400Gbps has become the mainstream speed requirement for current Artificial Intelligence Data Centers (AIDC). Larger, more advanced AIDC are already exploring ways to deploy 800Gbps and even 1.6Tbps network transmission capabilities. So, what strategies can effectively boost optical transmission speeds to meet these escalating demands? 

Source：https://ethernetalliance.org

The above optical module rate combination diagram shows three methods to achieve a 100Gbps transmission rate: first, using four 25G lanes (4x25G); second, using two lanes with an increased bit rate of 50G each (2x50G); and third, utilizing a single 100G channel. These methods offer flexible, high-speed solutions tailored to diverse network needs, ensuring optimized data transmission for modern infrastructure.
To achieve ultra-high-speed Ethernet transmission, there are two primary approaches: increasing the data rate of a single lane or adding additional transmission lanes. The specific implementation methods are as follows:

Source：https://ethernetalliance.org

1, To enhance the transmission rate of a single-channel signal, improvements in optical modulation methods are key. Currently, there are several mature, cost-effective optical modulation techniques available, which include:

• NRZ (Non-Return to Zero, also known as PAM-2, Pulse Amplitude Modulation with two levels): This technique supports transmission rates of up to 25G per channel and is widely used in existing equipment due to its reliability and broad application.

• PAM-4 (Pulse Amplitude Modulation with four levels): Compared to NRZ, PAM-4 offers a higher modulation level, enabling transmission rates of 50G per channel, making it an ideal choice for applications that require greater bandwidth without a significant increase in cost.

• 16-QAM (16-Level Quadrature Amplitude Modulation): For ultra-high-speed transmission, 16-QAM is typically used in coherent channel systems, supporting transmission rates of up to 100G per channel, making it suitable for demanding, high-capacity networks.

2, The optical transmission speed can be enhanced in two ways by aggregating multiple lanes, boosting efficiency and performance. 

Source：https://ethernetalliance.org

A.One method is to increase the number of physical channels. This primarily depends on the package of optical modules, which come in various form factors. Here are some of the most common optical module form factors:

• SFP (Small Form-factor Pluggable)

  An upgrade to the GBIC, SFP uses a dual-channel package and supports transmission rates of up to 1G. It's a widely used solution for network upgrades.

• SFP+

  Building on the SFP form factor, SFP+ supports higher transmission speeds of up to 10G, offering a more advanced solution for faster data transmission.

• QSFP (Quad Small Form-factor Pluggable)

  QSFP features a four-channel package, providing the equivalent of four SFP channels. This significantly boosts data throughput, making it ideal for high-speed applications.

• QSFP-DD (Double Density)

  As an enhanced version of QSFP, QSFP-DD comes with 8 channels, doubling the channel count compared to the standard QSFP. This allows for even higher data transmission rates.

• OSFP (Octal Small Form-factor Pluggable)

  Similar to QSFP-DD, OSFP also supports 8 channels. It offers high-density transmission capabilities, catering to the increasing demand for higher bandwidth in modern networks.

It's important to note that advancements in packaging technology can also increase both the number of optical fiber channels and overall costs. Therefore, it’s essential to strike a balance between performance and cost for a cost-effective, high-speed network design.

B.Another method is to expand the number of virtual channels, by using Wavelength Division Multiplexing (WDM) technology in single-mode fibers. WDM works by adding additional lasers to increase the number of channels, thereby achieving higher transmission speeds. However, this also leads to higher power consumption and increased system complexity, resulting in higher costs. As a result, WDM technology is typically employed by telecommunications operators for long-distance, high-bandwidth, and high-speed transmission requirements.

In summary, we now have a comprehensive understanding of the demand for ultra-high-speed Ethernet transmission and the methods to achieve it, which also establishes the foundation for further understanding the pre-terminated fiber optic solutions of the AIDC.