A novel third option is emerging for data center interconnects between short-reach copper and power-hungry optics. Point2 CEO Sean Park joins Vik Sekar to explain his company's Active RF Cable (ARC) technology, which sends high-frequency radio signals over a flexible plastic waveguide. Park details how this approach targets the critical 5-10 meter "scale-up" problem for AI clusters, claiming significant advantages in cable density, power efficiency, and latency over existing solutions.

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"The bandwidth limitation simply comes from the existence of electrons. And this plastic, it doesn't have electron. So, in terms of bandwidth, it is unlimited. Bandwidth is unlimited. So, once our silicon works, we don't have to really change the this cable at all. Just scale the silicon, then it will it will be used for higher data rate."
— Sean Park, Point2 Technology

Key Takeaways:

- The interconnect choice is no longer just copper vs. optics. Point2's Active RF Cable (ARC) creates a third category, sending 100-200 GHz signals over a plastic waveguide for the 5-10 meter reach AI scale-up requires.

- The core density advantage is 4x over copper. ARC uses a single plastic core instead of a differential pair (2x gain), then sends two channels per core using frequency division multiplexing (another 2x gain).

- The power savings come from silicon simplicity. By avoiding the laser, DSP, and TIA of optical modules, a 1.6T ARC module consumes <10 watts (~5 pJ/bit), with a roadmap to <2 pJ/bit for co-packaged versions.

- The latency improvement is three orders of magnitude. Because it requires no DSP, ARC latency is in the sub-nanosecond range — 1,000x better than DSP-based optical solutions, which is critical for all-reduce operations.

- The cable itself has a clear scaling path that copper lacks. A plastic waveguide is a dielectric with theoretically unlimited bandwidth, free of the skin effect that limits copper. Future speed gains will come from silicon shrinks alone.

- Practicality in the rack is a key feature. The flexible plastic cable has a 4.7 mm bend radius, tight enough to wrap around a finger, making it easier to route in dense chassis than fragile optical fiber.

Chapters:
0:00 Intro: RF Over Plastic
3:06 The Third Option
8:27 Investor Validation
13:20 How E-Tube Works
15:16 The 4x Density Advantage
18:28 Inside the OSFP Module
29:51 4.7mm Bend Radius
34:20 Roadmap to Co-Packaging
36:09 The No-Gearbox Advantage
42:00 Biggest Challenges
49:57 The Physics of Scaling
51:00 Origin Story: Wallpaper TV

Mentioned in this episode:

- Plastic Cables for AI Clusters: Can Point2’s E-Tube Disrupt Copper and Optics? (Vik's Newsletter, paid): https://www.viksnewsletter.com/p/plastic-cables-for-ai-clusters-etube

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