Meta open-sources MetaRoCE and shows IcePack liquid-cooled rack and 102.4T IceCube switch at OCP

Meta's engineering post covers scale-up, scale-out and scale-across networks for AI training. IcePack is Meta's first liquid-cooled network rack, which signals that switch heat density has reached GPU-rack levels. IceCube is a 102.4T switch platform. Flattened Planar Fabric is a multiplane backend design meant to cut network tiers in very large clusters.

MetaRoCE is the most significant release for the wider ecosystem. It is an open-source transport protocol tuned for AI collective traffic, in the same space as Google's Falcon and NVIDIA's Spectrum-X congestion control. Open-sourcing it lets other operators and vendors implement it without licensing. It also strengthens Meta's position in the Ultra Ethernet-era standards fight.

The release complements rather than replaces NVIDIA: Meta is simultaneously adopting NVIDIA Spectrum-6. The pattern is that hyperscalers adopt vendor silicon while owning the protocols and topology above it.

It arrived on the same day as Muse Wonder, so Meta is pushing both frontier models and the infrastructure to train them. Watch for whether other OCP members adopt MetaRoCE, or whether it stays a Meta-internal standard released in public.