Quantum Key Distribution (QKD):
Context:
A Bangalore-based startup, QNu Labs Pvt. Ltd., has successfully demonstrated India's first extensive Quantum Key Distribution (QKD) network (spanning over 500 kilometers)
The demonstration, supported by the Department of Science and Technology (DST) under the National Quantum Mission (NQM), was deployed over existing optical fiber infrastructure.
The Indian Army's Southern Command also contributed by providing its test-bed optical fiber network
What is Quantum Key Distribution (QKD)?
QKD is a secure communication method used for exchanging encryption keys known only between the shared parties
Unlike conventional key distribution, which relies on mathematical calculations, QKD uses a quantum system based on the fundamental laws of nature to protect data
Its security relies on quantum physics principles such as the no-cloning theorem which states it is impossible to create identical copies of an unknown quantum state
Any attempt by an eavesdropper to "look at" or intercept the system will disturb it.
This change will be detected by the intended parties
How does it Works?
QKD works by transmitting light particles(photons) over fiber optic cables
Each photon has a random quantum state, and collectively they form a stream of ones and zeros (qubits)
This stream is used to produce a shared, secret key.
Then it can then be used to encrypt and decrypt messages
Challenges
A primary challenge is the distance photons can travel over modern fiber optic cables before degrading is often limited (e.g., upward of 100 km).