Quantum Corridor, Ciena, and Toshiba completed a field trial on August 5, 2026, encrypting 1.6 terabits per second of optical capacity between a Chicago data center and a Hammond, Indiana data center, roughly 21.8 kilometers of metro fiber, using two different quantum-era security methods running at the same time on the same network. The trial paired post-quantum cryptography with quantum key distribution (QKD), rather than choosing one approach over the other, which is itself the more interesting part of this announcement.
Two different answers to the same threat, run together
Post-quantum cryptography and QKD solve the same underlying problem, protecting encrypted data against decryption by a future large-scale quantum computer, through entirely different mechanisms. PQC uses new classical algorithms, run on ordinary hardware, that are believed to resist quantum attacks. QKD uses the physics of quantum states to detect eavesdropping and distribute encryption keys, which requires dedicated hardware and, in this case, Toshiba's QKD servers generating the quantum-derived symmetric keys. Running both simultaneously over the same dense wavelength-division multiplexing (DWDM) infrastructure, alongside ordinary classical data traffic on the same fiber pairs, is a statement about defense in depth: if one approach turns out to have a weakness that is not currently known, the other is still standing.
The hardware doing the work
The encryption ran on Ciena's Waveserver platform with WaveLogic 6 Extreme coherent optics, applying wire-speed optical-layer AES-256-GCM encryption using NIST-certified post-quantum algorithms for key establishment, layered with Toshiba's QKD-derived keys. That combination matters for a reason beyond the cryptography itself: it ran on live, in-production network infrastructure rather than a lab testbed, and it worked at 1.6 Tb/s, a real commercial-grade capacity figure, not a demonstration throughput far below what an actual network operator needs.
Why "harvest now, decrypt later" is the actual threat model here
The trial's stated purpose is defending against "harvest now, decrypt later," the practice of an adversary recording encrypted traffic today with the intent of decrypting it once a sufficiently capable quantum computer exists. That threat model is why this trial matters now, well before any quantum computer breaks RSA or ECC at scale. Data encrypted today with vulnerable algorithms is already exposed to a future break, which our PQC migration deadlines piece covers in terms of NIST and NSA's published timelines. A field trial proving PQC and QKD run together, at commercial speed, on infrastructure that already exists, is a concrete answer to "we're not ready yet."
Crypto-agility without ripping out hardware
The trial also demonstrated the transition working through a software upgrade path rather than a hardware replacement, meaning existing Ciena Waveserver deployments plausibly gain this protection without a physical infrastructure swap. That is directly relevant to organizations facing compliance mandates, the trial specifically cites U.S. and French cybersecurity requirements, since a software-upgrade path is a materially cheaper and faster migration story than a hardware refresh cycle.
What to watch next
The next test is whether this specific PQC-plus-QKD combination gets adopted beyond a single field trial route, into networks carrying traffic for organizations with real regulatory deadlines to hit. Our quantum networking piece covers how QKD and quantum-safe networking fit into the broader distributed quantum computing picture beyond cryptography alone.