“Whereas the IEEE P802.3dj challenge is working towards defining 200G per lane for Ethernet by late 2026, the {industry} is (loudly) asking for 400G per lane yesterday, if not sooner,” Jones wrote in a latest Ethernet Alliance weblog.
In a put up about Ethernet’s AI evolution, John D’Ambrosia wrote concerning the growth of 400 Gb/s signaling: “The IEEE P802.3dj challenge is defining the underlying 200Gb/s PAM4 signaling applied sciences in assist of chip-to-chip, chip-to-module, backplane, copper cable, and single-mode fiber applied sciences to facilitate the quite a few specs for 200GbE, 400GbE, 800GbE, and 1.6TbE. These efforts are anticipated to be accomplished within the second half of 2026 so AI purposes could have some near-term options to leverage. Nonetheless, the staggering development charges of computational energy require the {industry} to start out trying past 200 Gb/sec primarily based signaling now for the networks of the long run.”
“One of many outcomes of [the TEF] occasion was the belief the event of 400Gb/sec signaling can be an industry-wide downside. It wasn’t solely an software, community, part, or interconnect downside,” said D’Ambrosia, who’s a distinguished engineer with the Datacom Requirements Analysis group at Futurewei Applied sciences, a U.S. subsidiary of Huawei, and the chair of the IEEE P802.3dj 200Gb/sec, 400Gb/sec, 800Gb/sec and 1.6Tb/sec Process Power. “Overcoming the challenges to assist 400 Gb/s signaling will doubtless require all of the instruments obtainable for every of the assorted layers and elements.”
The IEEE in January started an “802.3 Ethernet Interconnect for AI” evaluation, a multivendor effort to evaluate numerous key necessities for Ethernet and AI, reminiscent of:
- What are the interconnect necessities for the completely different AI networks?
- What are the efficiency necessities of those interconnects?
- What are the priorities for the event of those interconnects?
- What tradeoffs will be made between latency and resilience/attain/energy?
“We’re actively making an attempt to determine and perceive which set of issues to resolve right here,” Jones stated.
Ethernet vs. InfiniBand
There’s additionally the pattern of shifting AI networks towards Ethernet moderately than present connectivity stalwart InfiniBand.