QNu Labs, BISAG-N and IIT Gandhinagar Demonstrate 5 km-Scale Free-Space QKD Link

Insider Brief

• QNu Labs, BISAG-N and IIT Gandhinagar completed a 5.56-kilometer free-space quantum key distribution trial, integrating keys transmitted through the atmosphere with a post-quantum cryptography application.
• The link achieved a secure key rate of 230–260 bits per second with a quantum bit error rate below 5%, supporting successful encryption, transmission and decryption of a test message.
• The hybrid system combined quantum key distribution with post-quantum cryptography and quantum random number generation, with the software security layer designed to remain operational if the quantum channel becomes unavailable.

PRESS RELEASE — QNu Labs (www.qnulabs.com), a global leader in end-to-end hybrid quantum cybersecurity solutions, along with the Bhaskaracharya National Institute for Space Applications and Geo-informatics (BISAG-N), and IIT Gandhinagar, have successfully completed a 5.56 km free-space Quantum Key Distribution (QKD) field trial, marking India’s first free-space QKD link at the 5 km scale. The field trial demonstrates the ability to establish and maintain a quantum-secured communication link over open atmosphere while integrating QKD generated keys with a post-quantum cryptography (PQC) enabled application environment.