QNu Labs Validates its Quantum Key Distribution Performance for Encrypted Communication

IIT Madras-incubated deeptech startup QNu Labs has released findings from a joint research study with VIAVI Solutions, a test, measurement, and assurance solutions company. The study assesses the real-world performance of its ARMOS Quantum Key Distribution (QKD) platform. 

QKD is a method of communication where encryption keys between two parties are exchanged using quantum computing, and not mathematical modelling.

The study used VIAVI’s MAP-300 platform to evaluate deployment readiness and operational capability across telecom networks.

The results showed that ARMOS can generate secure keys over distances of up to 200 km of standard telecom fibre without signal amplification, while maintaining quantum bit error rates below 4%. 

The study also found that the system can operate alongside 10 Gbps classical data traffic on the same fibre without affecting performance.

“This validation reflects the depth of engineering and real-world readiness we have built. It demonstrates that quantum-safe communication can be implemented at scale,” Sunil Gupta, Co-founder and CEO, QNu Labs, said in a statement. 

At metro distances of about 50 km, ARMOS achieved secure key generation rates of up to 8,000 bits per second, the study showed. At 200 km, it sustained rates of around 200 bits per second, supporting encryption across different network conditions.

A key feature highlighted in the study is the use of a decoy-state Differential Phase Shift protocol. This allows the system to tolerate up to 40 dB of channel loss, extending transmission range compared to conventional QKD systems.

The platform also showed resilience during simulated disruptions. It detected fibre cuts and restored secure key generation within minutes without manual intervention. The system also maintained stability under conditions such as attenuation and polarisation changes.

QNu Labs confirmed the readiness for deployment across enterprise and critical infrastructure networks. Sudiptaa Paul Choudhury, Chief Marketing Officer at QNu Labs, said the study helps shift quantum security from “abstract promise to demonstrable capability.”

Additionally, the report outlined further research plans, including testing under higher data loads and studying hybrid quantum-classical networks. The companies aim to support scalable quantum-secure communication frameworks through these efforts.