Broadcom Ships Tomahawk6 – Davisson, Industry’s First 102.4-Tbps CPO Ethernet Switch for AI Networking

Broadcom. has begun shipping the Tomahawk 6 – Davisson (TH6-Davisson), its third-generation Co-Packaged Optics (CPO) Ethernet switch, designed for AI networking. The BCM78919 device delivers a switching capacity of 102.4 terabits per second, operating at 200 Gbps per channel with 16 x 6.4 Tbps Davisson DR Optical Engines. It supports scale-up clusters of 512 XPUs and two-tier networks with up to 100,000+ XPUs, compliant with IEEE 802.3 standards for 400G and 800G interoperability with DR-based transceivers, LPO, and CPO optical interconnects.

The TH6-Davisson integrates TSMC Compact Universal Photonic Engine (COUPE) technology with advanced substrate-level multi-chip packaging, reducing optical interconnect power consumption by 70% compared to pluggable solutions. Its design, incorporating field-replaceable ELSFP laser modules, minimizes signal conditioning needs, trace loss, and reflections. The switch enhances link stability by integrating optical engines directly onto the Ethernet switch package, reducing manufacturing and test variability compared to pluggable transceivers, as validated by a TH5-Bailly link flap study.

The platform addresses the increasing east-west traffic demands in data centers driven by AI training and inference, supporting large-scale XPU and GPU data exchanges. Broadcom is developing its fourth-generation CPO solution, targeting...