Cisco and NVIDIA are drafting a new pluggable optics form factor built around 400G SerDes lanes, a doubling of today's common 200G lanes that lets a 1.6Tbps module run on just four lanes. Ahead of the OCP Global Summit, Cisco briefed analysts on the design — called USFP, for ultra-dense small form factor — and on a stack of related silicon and software announcements.

Why does USFP matter? Because the jump from 200G to 400G SerDes changes the lane math across the board. Four 400G lanes get you to 1.6Tbps; 16 lanes scale to 6.4T aggregate, and 32 lanes reach 12.8T. Cisco and NVIDIA are jointly drafting the multi-source specification so other vendors can build compatible modules — with both companies behind it, USFP is positioned to become an industry standard for the 1.6Tbps Ethernet generation.

Notably, today's QSFP and OSFP shells weren't deemed sufficient for next-generation speeds. That's the quiet admission here: the incumbent form factors hit a density wall before 1.6Tbps modules arrive, which is why a new shell needs a multi-source spec now rather than later.

What's shipping and what's coming in Silicon One?

The optics work pairs with three silicon announcements:

• Silicon One G300 — now in first-shipped Cisco 8000 and N9000 systems, delivering 102.4T of capacity across 1.6T ports.
• Silicon One G302 — drives a 51.2T front-end top-of-rack switch using 200G SerDes, arriving in Q4 2026.
• Silicon One A100L — targets lower-cost 10G/1G out-of-band management switches, a segment most observers had written off as commoditized.

The A100L is the odd one out, and the most interesting. Custom silicon normally shows up in high-performance fabric switches, where the performance premium justifies the engineering spend. Management-box silicon on 1G/10G rack networks is usually a volume play you buy off the shelf. Cisco said the A100L proves the architecture scales and that hyperscale clients wanted to run SONiC on everything.

What's still unclear about the A100L?

Licensing is a genuine open question. Analysts asked whether the model will be perpetual, like the C1300, or closer to the Nexus 9K series — and didn't get a clear answer, so it's fair to call it TBD for now. The concern is straightforward: if you're doing custom silicon instead of, say, a Marvell Prestora-class merchant part and not capturing software revenue on top, the economics look tough.

What does Live Protect change for operators?

On the software side, Live Protect for Cisco SONiC on Nexus One adds runtime vulnerability shielding to N9000 switches. It applies policy to a running system, so operators can shrink the exploit window and protect a box before scheduling a conventional patch and reboot. Availability is slated for Q2 2027 in Cisco-validated SONiC environments — notable timing, given Cisco SONiC itself is set to arrive in 2027.

Customers will also pick between two operating models for SONiC. A community or custom track offers full customization and source access for maximum control; a turnkey Cisco-validated track provides a defined upgrade path plus professional services. Cisco is also supporting NVIDIA switching platforms alongside the open-source OS — its Spectrum-X work with NVIDIA is an option we've covered before.

The short version: USFP is the headline and likely the standard to watch, G302 is a meaningful milestone on its own, and the A100L pushing custom silicon into sub-1Tbps management switching is the move almost nobody expected.