India’s National Quantum Mission (NQM), launched in April 2023 with a budget of ₹6,000 crore, aims to harness quantum physics for next-generation communication and sensing technologies. Planned for implementation from 2023 to 2031, the mission seeks to enhance secure communication systems, including a quantum satellite expected to launch in 2–3 years.

Quantum communication leverages the principles of quantum physics to develop encryption methods resistant to hacking, even by advanced quantum computers. Conventional encryption relies on mathematical complexity, which quantum computers could potentially crack. In contrast, quantum cryptography, particularly Quantum Key Distribution (QKD), ensures unconditional security by detecting any attempt at eavesdropping through changes in quantum states or entangled particles.

India’s quantum satellite will demonstrate secure data transmission using QKD over long distances. Recent studies, such as those from the Raman Research Institute, Bengaluru, identified Ladakh’s clear skies as ideal for satellite-based QKD, enabling signals over 500 km.

However, QKD faces challenges. Unlike traditional cryptography, it requires specialized hardware that is difficult to upgrade, involves higher infrastructure costs, and is vulnerable to denial-of-service attacks. Recognizing these limitations, researchers are also exploring post-quantum cryptography—classical encryption techniques designed to resist attacks from quantum computers.

Globally, China leads with the largest QKD network supported by three quantum satellites. India’s entry into this domain marks a critical step toward securing its communications and achieving technological leadership in quantum science.

While practical implementation may take a decade, the NQM aims to establish a robust framework for quantum technologies, setting the stage for advancements in cybersecurity, defense, and scientific research. India’s quantum satellite is not just a technological milestone but also a leap toward future-proofing communication against emerging threats.