As AI networking requirements grow, the Ethernet Alliance will take up a 400G/lane project while the Ultra Ethernet Consortium will prioritize flexible congestion management and small-message performance.
2025 marked a year of progress for Ethernet with multiple standards and specifications reaching completion as the networking industry works to keep pace with AI and HPC demands.
Among the leading efforts for Ethernet in 2025 was the Ultra Ethernet Consortium, an open-source effort under the governance of the Linux Foundation that aims to enhance Ethernet to better compete and surpass the capabilities of Infiniband. The Ultra Ethernet Consortium (UEC) released its 1.0 specification in June, with an update to 1.0.1 in September.
Looking at the core Ethernet standards, the IEEE 802.3dj standard moved closer to completion, enabling a new era of 1.6 Terabit per second (Tbps) high-speed operations.
“The Ethernet Alliance had a strong year in 2025, marked by continued growth and technical leadership,” Peter Jones, chair of the Ethernet Alliance, told Network World.
Ethernet getting broader and faster
Jones noted that the IEEE 802.3dj standard, which defines 200G/400G/800G/1.6T at 200G/lane, is on track for completion in late 2026. Early 200G/lane products are expected to reach the market during the year.
With 200G/lane almost done, the community is already looking ahead. “While this work is receiving substantial attention, the community is already preparing for the next step: initiating a 400G/lane project to address the demands of the hyperscalers for AI networking,” Jones said.
The 400G/lane project represents the next step in Ethernet’s bandwidth evolution. The Ethernet Alliance will continue its ecosystem work in 2026, demonstrating interoperability at multiple events and organizing another 200G/lane plugfest.
Ultra Ethernet adapts to evolving AI workloads
Following the release of its 1.0 specification, the Ultra Ethernet Consortium is tackling three technical priorities in 2026 aimed at improving Ethernet performance for AI and HPC workloads. The first is Programmable Congestion Management (PCM).
“AI and HPC workloads are rapidly evolving,” Chad Hintz, co-chair of marketing at UEC and principal member of technical staff at AMD, told Network World. “To address these rapid changes, flexible congestion management mechanisms are required.”
PCM will enable anyone to implement a new congestion control algorithm using a standard language, and that algorithm will work on any NIC that supports UE PCM.
The UEC is also standardizing Congestion Signaling (CSIG), which allows packets to carry high-fidelity information about network congestion. This enables the transport protocol to react more accurately and quickly to changing conditions.
The second priority addresses small message performance. The Ultra Ethernet Transport (UET) 1.0 protocol is designed to support up to a million hosts coordinating as part of a single job. To achieve this scale, a basic UET packet has 104 bytes of headers. That overhead is just 2.5% for 4096-byte packets but becomes more significant for smaller transactions like 256-byte transfers. The smaller packet overhead will improve efficiency for workloads with small payloads, whether HPC workloads or local scale-up networks.
“UEC is pursuing optimizations across all layers of the stack, including a reduced-size forwarding header, looking to cut this overhead in half for optimized deployments,” Hintz said.
The third focus is In-Network Collectives (INC) for Ethernet networks. By moving the reduction operation common to AI and HPC workloads from hosts into the network, INC can help to improve performance on certain workloads.
Ethernet development extends beyond AI
While AI networking captures much of the attention, IEEE 802.3 maintains active work across a broader landscape.
Jones noted that projects underway include 10 Mb/s single-pair multidrop Ethernet, 100 Mb/s long-reach single-pair Ethernet and asymmetric Ethernet for automotive sensor networks. The group is also working on metadata services to support advanced applications, including those defined by the Ultra Ethernet Consortium.
In a move toward open collaboration, IEEE 802.3 is launching an open source project to produce YANG modules for the standard.
The theme running through all of Ethernet’s 2026 work is speed. Not just the speed of the technology itself, but the speed at which the industry must move to stay ahead of customer demands.
“As an industry, the challenge remains unchanged: moving as fast as possible to stay ahead of accelerating customer demands,” Jones said. “In that sense, 2026 may feel very much like 2025. Proof that progress in Ethernet, as the saying goes, no good deed goes unpunished.”
