Broadcom challenges Nvidia with 51.2T switch silicon • The Register


Broadcom says it has doubled the capability of its business silicon swap with the launch of the 51.2 Tbps Tomahawk5 ASIC this week.

Broadcom’s Tomahawk line is aimed toward cloud and hyperscale prospects, and its newest ASIC guarantees to ship a considerable enhance in port density whereas lowering energy consumption in comparison with earlier era chips. Tomahawk5 additionally brings the corporate in control with rival Nvidia, which launched its personal 51.2Tbps Ethernet swap at GTC this spring.

Utilizing the ASIC, the corporate expects OEMs, which Tomahawk5 is already sampling, to start out transport switches with 64 800Gbps ports or 128 400Gbps ports or 256 200Gbps ports early subsequent yr.

“Each two years we have been doubling the bandwidth of silicon,” mentioned Pete Del Vecchio, product line supervisor. Register. “Since 2010, we now have an 8-fold enhance in bandwidth, and each era we additionally enhance power effectivity. So now we’re 95 % extra environment friendly than 12 years in the past.”

Nonetheless, it needs to be famous that, just like the 25.6Tbps Tomahawk4 it replaces, Broadcom’s newest chip remains to be caught on a 100Gbps PAM4 serializer/deserializer (SerDes). This successfully limits throughput per port to 800 Gbps when utilizing QSFP-DD optical connectors. So whereas Broadcom has managed to double the capability of its silicon swap, it hasn’t truly doubled the port speeds. Not that prospects are clamoring for extra pace simply but.

In line with Broadcom executives, adoption of 400 Gbps modules remains to be in its infancy, even amongst performance-hungry hyperscalers, which account for simply 15 % of the entire Ethernet market by income. By 2026, Broadcom expects 400G ports to exceed 50 % of Ethernet income.

These figures roughly align with the findings of a current Dell’Oro Group report, though analysts estimate market penetration for 400 Gbps switching to be nearer to 10 %. Within the first quarter of 2021, the group reported that 400Gbps swap shipments had exceeded 800,000 ports, and that quantity is anticipated to proceed to rise over the subsequent yr, pushed by robust demand from cloud suppliers.

Nonetheless, the Tomahawk5 claims greater than double the switching capability. Enhancements to the chip structure, together with a transfer to a 5nm fabrication course of, allow the monolithic swap chip to realize vital energy financial savings.

In line with Broadcom, the chip consumes lower than one watt for each 100 Gb of capability. Which means at full energy, the chip makes use of lower than 500W, which Broadcom says will permit OEMs to proceed with air-cooled switches powered by the chip.

“Doubling the bandwidth truly offers you a 6x discount in value, energy and complexity,” mentioned Del Vecchio, evaluating the chip to the earlier era Tomahawk4.

The ASIC additionally has a variety of options tailor-made to Hyperscape HPC workloads, together with community virtualization and segmentation, one-pass VxLAN bridging and routing, in addition to “cognitive routing” capabilities designed to scale back job completion instances by avoiding congestion.

“The site visitors traits you could have for AI/ML are usually completely different than what you’ll have for normal compute and storage site visitors,” Del Vecchio defined, including that by routing round potential sources of congestion, the swap can scale back the latency and enhance efficiency for AI/ML workloads.

Taken collectively, Broadcom says the Tomahawk5 is the very best performing single-switch ASIC accessible in the marketplace, however that declare is just not with out caveats. At GTC this spring, Nvidia confirmed off its 51.2 Tbps Spectrum-4 Ethernet swap.

Spectrum-4 relies on expertise gained from the Mellanox acquisition in 2019, and the swap options most of the similar capabilities as Broadcom’s Tomahawk5, together with assist for as much as 64 800Gbps ports in a single chassis. The swap, in addition to Nvidia’s BlueField-3 DPUs, are scheduled to start out transport later this yr.

So whereas Broadcom can declare to have overwhelmed Nvidia to market with a 51.2Tbps ASIC (technically that is a sampling), these chips nonetheless have to be built-in into the OEM chassis earlier than they make their knowledge middle debut. . This casts some doubt on which is able to attain prospects’ arms first, particularly given the present state of the provision chain. ®



Broadcom challenges Nvidia with 51.2T switch silicon • The Register

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