# Cisco Built a Quantum Switch. It Only Works One Way.

- slug: cisco-built-a-quantum-switch-it-only-works-one-way
- date: 2026-04-23
- category: Quantum Computing

The prototype converts between incompatible quantum encoding formats in under a nanosecond at room temperature on standard telecom fiber. Three of four promised encoding types are unvalidated, and the supporting research paper has not been published.

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