Because AI is pushing Ethernet standards exclusively for universal RDMA use.
The minimum to get into this party is already have 400gbE (QSFP 112) or 800 (QSFP-DD 112 and QSFP 224) and already working on 800 (QSFP-DD 112) or 1600 (QSFP-DD 224).
Broadcom doesn't belong to any of the AI-era SIGs, so they're trying to drag their networking fabric stuff up to speed to match, but they do belong to Ethernet Alliance and technically the IBTA (but the IBTA is no longer relevant since Nvidia bought Mellanox).
The SIG they need to belong to is the UALink Consortium, which is moving past simply RoCE/iWARP-style RDMA over Ethernet to CPU bus over Ethernet. In other words, Ultra Ethernet is trying to do multi-vendor super-computer stuff like how AMD did Hypertransport over Mellanox circa 2001-2015 (and this is why Nvidia bought Mellanox btw, they wanted to deprive AMD of an advantage that they no longer needed... they had already moved to external PCI-E fabric to replace Mellanox, and thus the brand switch to Infinity Fabric).
UALink is a socket-to-socket protocol that is PHY independent, and can use CXL (common with Intel-focused supercomputing), PCI-E (PCI over PCI-E, ie, normal non-CCNUMA hardware being babysat by the local CPU), InfinityFabric/XGMI (AMD CPU, AMD GPU), and others, while having native support for RDMA over Ultra Ethernet (200gbE and up) to glue clusters together across NUMA/UALink domains.
The UALink Consortium was founded by Alibaba, AMD, Apple, Astera Labs, AWS, Cisco, Google, Hewlett Packard Enterprise, Intel, Meta, Microsoft and Synopsys... notice the lack of Broadcom in that list. Nvidia is also not a member of this, as they desperately want a moat to keep the rest of the industry out.
The minimum to get into this party is already have 400gbE (QSFP 112) or 800 (QSFP-DD 112 and QSFP 224) and already working on 800 (QSFP-DD 112) or 1600 (QSFP-DD 224).
Broadcom doesn't belong to any of the AI-era SIGs, so they're trying to drag their networking fabric stuff up to speed to match, but they do belong to Ethernet Alliance and technically the IBTA (but the IBTA is no longer relevant since Nvidia bought Mellanox).
The SIG they need to belong to is the UALink Consortium, which is moving past simply RoCE/iWARP-style RDMA over Ethernet to CPU bus over Ethernet. In other words, Ultra Ethernet is trying to do multi-vendor super-computer stuff like how AMD did Hypertransport over Mellanox circa 2001-2015 (and this is why Nvidia bought Mellanox btw, they wanted to deprive AMD of an advantage that they no longer needed... they had already moved to external PCI-E fabric to replace Mellanox, and thus the brand switch to Infinity Fabric).
UALink is a socket-to-socket protocol that is PHY independent, and can use CXL (common with Intel-focused supercomputing), PCI-E (PCI over PCI-E, ie, normal non-CCNUMA hardware being babysat by the local CPU), InfinityFabric/XGMI (AMD CPU, AMD GPU), and others, while having native support for RDMA over Ultra Ethernet (200gbE and up) to glue clusters together across NUMA/UALink domains.
The UALink Consortium was founded by Alibaba, AMD, Apple, Astera Labs, AWS, Cisco, Google, Hewlett Packard Enterprise, Intel, Meta, Microsoft and Synopsys... notice the lack of Broadcom in that list. Nvidia is also not a member of this, as they desperately want a moat to keep the rest of the industry out.