India logs a 5.56 km night-time free-space quantum key link in Gujarat

On the night of September 27-28, 2026, QNu Labs, the Bhaskaracharya National Institute for Space Applications and Geo-informatics (BISAG-N), and IIT Gandhinagar held a 5.56 km free-space optical channel across Gujarat using QNu's Armos quantum key distribution (QKD) device. MeitY confirmed the trial in an October 3 release.

Free-space QKD is a secure-comms field trial: two sites beam single-photon or weak-coherent signals through open air, agree on a shared encryption key, and any eavesdropper leaves a detectable fingerprint. It is not a quantum computer, not a quantum internet, and not a record encrypted file transfer.

MeitY reports a quantum bit error rate below 5% and secure-key generation of 230-260 bits per second, enough to derive a 256-bit key in roughly one second at the upper end. The rate describes key material, not message throughput, so the channel fits rekeying rather than bulk data encryption.

The keys encrypted and decrypted test messages on BISAG-N's Vedic Kavach, a stack combining post-quantum cryptography with quantum random number generation. The Hindu Business Line and ANI carried the same MeitY figures.

The ministry did not publish the QKD protocol, wavelength, detector type, or atmospheric conditions. The result is a single-path field test, not an operational network, and the genuine news is the 5.56 km mark, not a categorical first in free-space quantum communication.