The Defence Research and Development Organisation (DRDO) has configured and tested a Quantum Key Distribution (QKD) platform on the live network of the dynamic test ranges at the Proof and Experimental Establishment (PXE) in Chandipur, Odisha. The platform protects the real-time observations and telemetry generated during artillery and armoured weapon trials. The test marks a shift for Indian quantum-secured communications, from laboratory demonstrations to an operational defence network.
What Is Quantum Key Distribution?
Quantum Key Distribution is a method of sharing a secret encryption key between two parties using particles of light. Any attempt to measure or copy these particles disturbs their quantum state, so the two sides can detect eavesdropping before they use the key.
The full form of QKD is Quantum Key Distribution. It does not encrypt the message itself. Instead, it produces a shared random key that is handed to a conventional encryption system, usually a symmetric cipher such as AES, which then locks and unlocks the actual data. This distinction matters: QKD secures the key supply, while the cipher secures the content.
Traditional public-key cryptography, including RSA and elliptic-curve systems, rests on mathematical problems that are hard for ordinary computers to solve. A sufficiently powerful quantum computer running Shor’s algorithm could break these systems. QKD takes a different route. Its security comes from physics rather than from the assumed difficulty of a calculation.
Most QKD systems send very weak pulses of light or single photons through an optical fibre. Some use free-space optical links instead. Because quantum states cannot be copied perfectly, an eavesdropper cannot make a silent duplicate of the key. The act of measurement leaves a trace. This property is called the no-cloning theorem, and it is the foundation of QKD’s interception detection.
The idea was proposed in 1984 by Charles Bennett and Gilles Brassard, whose BB84 protocol remains the benchmark for most commercial systems. In 1991, Artur Ekert proposed E91, which uses entangled photon pairs. Modern Indian work, including the DRDO and IIT Delhi experiments, has used both prepare-and-measure and entanglement-based approaches.
Analogy · A Seal That Cannot Be Faked Expand analogy
Think of the quantum key as a soap bubble sent through a narrow pipe. Anyone who touches it to read it pops it, and the receiver instantly knows the message was disturbed. Classical encryption is more like a locked box that can be copied and attacked later with better tools.
How QKD Detects an Eavesdropper
The sender, often called Alice, encodes each bit of the key in the quantum state of a photon. She chooses a random basis for every photon. The receiver, Bob, measures each arriving photon using a randomly chosen basis of his own. After transmission, the two compare which bases they used over an ordinary authenticated channel and keep only the bits where the bases matched.
They then sacrifice a sample of the remaining bits to estimate the Quantum Bit Error Rate (QBER), which is the share of bits that arrived incorrectly. Noise in the fibre also causes errors, so a high QBER does not prove that someone tapped the line. But if the error rate crosses a pre-set security threshold, the key is discarded. If it stays low, the parties run error correction and privacy amplification to produce a shorter, provably secret key.
One limitation is easy to miss. QKD distributes keys, but it does not confirm who is at the other end. The classical channel used to coordinate the protocol must be authenticated separately, usually with pre-shared secrets or post-quantum signatures. The security of the whole system also depends on the hardware, the random number generator, and the protection of the endpoints.
What Exactly Did DRDO Test at PXE Chandipur?
DRDO announced on 14 October 2026 that the QKD platform had been configured and tested on the live network of the dynamic test ranges at PXE Chandipur. The system was used to protect real-time observations and telemetry linked to artillery and armoured weapon tests and evaluation. DRDO described the trial as a practical use case for quantum-secured communication in a working defence testing environment.
| Detail | Information |
|---|---|
| Announcement date | 14 October 2026 |
| Organisation | DRDO, under the Ministry of Defence |
| Facility | PXE, Chandipur, Balasore district, Odisha |
| Network used | Live network of the dynamic test ranges |
| Developed by | Microelectronic Devices, Computational Systems and Cyber Security (MCC) cluster, DRDO |
| Production partner | Taqbit Labs, Bengaluru |
| Purpose | Protect real-time observations and telemetry from artillery and armoured weapon trials |
| Claimed capability | Eavesdropping detection with unconditional security for key distribution |
The platform was designed and developed under DRDO’s Microelectronic Devices, Computational Systems and Cyber Security (MCC) cluster. This cluster covers microelectronics, computing systems and cyber security, and it includes laboratories such as the Scientific Analysis Group (SAG), the Solid State Physics Laboratory (SSPL), the Centre for Artificial Intelligence and Robotics (CAIR), and the DRDO Young Scientist Laboratory for Quantum Technologies (DYSL-QT). Bengaluru-based Taqbit Labs was the production partner. DRDO said the system offers “unconditional security” along with the ability to detect eavesdropping.
PXE itself sits under DRDO’s Armament and Combat Engineering Systems cluster, since its job is weapon and armour testing. The QKD platform, however, comes from the MCC cluster. The trial therefore joins two different parts of the DRDO system: the armament test range that generates the data, and the electronics and cyber cluster that protects it.
Why Weapon Trial Telemetry Needs Protection
Telemetry is the stream of measurements that instruments send back during a test. At an artillery or armour range, this can include muzzle velocity, chamber pressure inside the barrel, the projectile’s flight path, dispersion, the point of impact, penetration results, and the behaviour of armour under fire. Sensors also record temperature, strain, vibration and the performance of sub-systems.
This data is valuable to an adversary because it describes how a weapon actually performs, long before it reaches frontline units. It can reveal the real range and accuracy of a gun, the weakness of an armour plate, or the failure of a particular trial. A leaked telemetry stream can save a rival years of research and expose which technologies are not yet reliable.
The risk does not end when a transmission is over. Under the “harvest now, decrypt later” threat, an adversary can record encrypted traffic today and store it until a powerful quantum computer becomes available. Data that must stay secret for decades, such as weapon designs and trial results, is the most exposed. This is why DRDO is moving quantum-secured key distribution onto a live range network rather than keeping it inside a laboratory.
PXE Chandipur: India’s Oldest Proof Range
The Proof and Experimental Establishment was established on 7 November 1895 as the Proof Department, with its headquarters at Balasore and Lieutenant R.T. Moorre as its head. It came under DRDO’s administrative control in October 1958, making it the oldest establishment in the organisation. Lieutenant Colonel B.N. Mitra became the first Indian to head it on 15 July 1947.
The word “proof” in its name refers to the testing of arms and ammunition before they are accepted for service. PXE conducts design and development trials for guns, mortars, rockets, recoilless launchers, tank guns and naval guns, along with their ammunition. It also evaluates armour plates, tank turrets, infantry combat vehicles and proximity fuzes. Over its history, it has been associated with programmes such as the Arjun main battle tank, the Pinaka multi-barrel rocket launcher and the Indian Field Gun.
Its location is central to its role. Chandipur sits on the Odisha coast in Balasore district, and the range has a notified area of about 50 km along the sea coast and 50 km into the sea. During low tide, the water recedes roughly three kilometres, which gives the range a wide natural testing area. The crescent-shaped coastline allows firing at different bearings without crossing busy air or sea routes.
PXE should not be confused with the Integrated Test Range (ITR), which also operates in the Chandipur area. ITR is DRDO’s missile flight-test facility and runs the launch complex at Dr Abdul Kalam Island, formerly Wheeler Island. PXE handles guns, ammunition and armour. ITR handles missile launches, tracking and flight data. Both sit on the same coastal stretch but serve different testing roles.
From Prayagraj to Chandipur: India’s QKD Milestones
The Chandipur trial did not emerge from nowhere. It rests on a series of demonstrations built over four years by DRDO, IIT Delhi and a small group of industry and academic partners.
| Date | Milestone | Key detail |
|---|---|---|
| February 2022 | First intercity QKD link in India | DRDO and IIT Delhi connected Prayagraj and Vindhyachal over more than 100 km of commercial-grade dark fibre, with sifted key rates of up to 10 kHz |
| 2023 | Long-distance phase-encoded QKD | The IIT Delhi research group reported a 380 km phase-encoded QKD experiment |
| 2024 | Entanglement-based QKD in fibre | Keys were distributed over a 100 km fibre spool, with additional lab and campus links of 50 km and 8 km |
| June 2025 | Free-space entanglement demonstration | DRDO and IIT Delhi achieved secure communication over more than 1 km in open air, with a secure key rate of about 240 bits per second and a QBER below 7 per cent |
| July 2026 | Military field trials | DRDO and Taqbit Labs tested a fibre-based system over 100 km between Prayagraj and Vindhyachal, recording 26 dB loss, a 6 per cent QBER and a secure key rate of about 5 kbps |
| October 2026 | Live range network | The QKD platform was configured and tested on the operational network at PXE Chandipur |
The July 2026 trial was significant because DRDO described the system as “productised” rather than experimental. A secure key rate of about 5 kilobits per second is modest by commercial data standards, but it is enough for encrypted text and low-bandwidth voice traffic. That is the kind of traffic that carries test observations between instrumentation sites on a range.
These projects have been supported through DRDO’s Directorate of Futuristic Technology Management (DFTM) and its Defence-Industry-Academia Centres of Excellence (DIA-CoEs). DRDO has set up 15 such centres at institutions including the IITs, the Indian Institute of Science and several universities. Taqbit Labs has worked with DRDO on QKD systems for the Indian Armed Forces since 2020, which explains how a laboratory concept moved into a rugged military package.
QKD vs Post-Quantum Cryptography: The Key Difference
Quantum Key Distribution uses physics to distribute keys over a dedicated optical link and detects interception. Post-quantum cryptography uses new mathematical algorithms that resist quantum attacks and runs on existing software and networks. The two are complementary, and many planners expect hybrid systems that combine both.
The confusion between the two is common because both are described as quantum-safe. They solve the same problem in different ways. QKD protects the key exchange by making eavesdropping physically detectable. Post-quantum cryptography (PQC) protects data by using mathematical problems that neither classical nor quantum computers can solve efficiently.
| Feature | Quantum Key Distribution | Post-Quantum Cryptography |
|---|---|---|
| Security basis | Quantum physics and the no-cloning theorem | Hard mathematical problems such as lattices and hash functions |
| Hardware | Dedicated quantum hardware, optical fibre or free-space link | Software that runs on existing computers and networks |
| Distance | Limited by photon loss and fibre quality, extended using trusted nodes or satellites | Not limited by optical loss |
| Eavesdropping detection | Built into the key exchange | Not a design feature |
| Standards | ISO and ETSI specifications | NIST FIPS 203, 204 and 205, finalised in 2024 |
| Typical use | Very high assurance links where key secrecy must last decades | Broad migration of existing systems and networks |
The National Institute of Standards and Technology (NIST) in the United States finalised three post-quantum standards in 2024. FIPS 203 defines ML-KEM, a key-encapsulation mechanism. FIPS 204 defines ML-DSA for digital signatures. FIPS 205 defines SLH-DSA, a hash-based signature scheme. These algorithms are designed to drop into existing systems with far less disruption than a dedicated quantum link.
QKD has its own standards, including ISO/IEC 23837 for security requirements and ETSI specifications for key delivery interfaces. Even so, some national agencies remain cautious. The US National Security Agency has said it does not support QKD for national security systems, arguing that its practical security depends on hardware and engineering, that it cannot authenticate the source on its own, and that it raises infrastructure and denial-of-service risks. India’s approach appears to treat QKD as one layer in a wider quantum-safe architecture rather than a replacement for every cryptographic tool.
National Quantum Mission and India’s Quantum Roadmap
The National Quantum Mission (NQM) was approved by the Union Cabinet on 19 April 2023 with an outlay of ₹6,003.65 crore for the period from 2023-24 to 2030-31. The Department of Science and Technology (DST) implements the mission. It covers four technology verticals: quantum computing, quantum communication, quantum sensing and metrology, and quantum materials and devices.
| Vertical | Thematic Hub host |
|---|---|
| Quantum Computing | Indian Institute of Science, Bengaluru, with C-DAC |
| Quantum Communication | IIT Madras with the Centre for Development of Telematics, New Delhi |
| Quantum Sensing and Metrology | IIT Bombay |
| Quantum Materials and Devices | IIT Delhi |
Each thematic hub is incorporated as a Section 8 company, a not-for-profit structure that gives it operational flexibility. The mission brings together 152 researchers from 43 institutions and supports startups working on quantum technologies. Its targets include intermediate-scale quantum computers with 50 to 1,000 physical qubits in eight years, satellite-based secure quantum communication over 2,000 km, and inter-city QKD over 2,000 km using trusted nodes on existing optical fibre.
India has reported rapid progress in one area. In April 2026, the government said a 1,000 km quantum communication network had been demonstrated under the mission using indigenous technology from QNu Labs, a supported startup. That is one of the longest QKD deployments reported anywhere since the mission began.
DRDO is a stakeholder in the mission and runs its own quantum programme in parallel. It inaugurated the Quantum Technology Research Centre (QTRC) at Metcalfe House in Delhi on 27 May 2025, with work led by the Scientific Analysis Group and the Solid State Physics Laboratory. The centre supports single-photon source testing, laser characterisation, atomic vapour cells and experimental QKD validation. DRDO’s DYSL-QT, based in Pune, works on quantum computing, communication and sensing, including a small superconducting quantum processor developed with TIFR and TCS.
What Still Stands Between the Lab and the Battlefield
The Chandipur test proves that a QKD platform can run on a live defence network. It does not prove that the armed forces can depend on it across every command and control link. Several engineering questions remain open.
What DRDO Has Not Disclosed
DRDO has not published the link distance, the number of nodes, the secure key rate, the duration of the trial, or the exact traffic that was protected. It has also not described how the classical channel was authenticated or whether the system was independently evaluated for implementation flaws. These details matter because the real-world security of QKD depends on the hardware and the surrounding network as much as on the physics of the key exchange.
A fibre-based QKD link also weakens with distance. Optical amplifiers cannot be used on the quantum channel because they would disturb the photon states, so long routes need trusted nodes that read and re-transmit the key. Each trusted node is a potential insider risk. Denial of service is another concern: an attacker who cuts or disturbs the fibre can simply stop the key exchange, even without reading it.
The Road Ahead
The next step is a multi-hop quantum network that connects command centres, laboratories and field units rather than a single point-to-point link. DRDO’s July 2026 trial was explicitly designed to support that architecture. The armed forces will also need ruggedised hardware, standard interfaces, trained operators and a maintenance chain that can support optical and electronic components in the field.
Many security planners now favour a hybrid approach. QKD protects the highest-value links where keys must remain secret for decades, while post-quantum algorithms secure the broader network, software and authentication layer. India’s quantum programme is moving in that direction, with DRDO, DST, academia and startups working on different parts of the chain. The Chandipur trial is an important marker of progress, but it is a step in a longer transition rather than the end of it.
Key Takeaways
- On 14 October 2026, DRDO configured and tested a Quantum Key Distribution (QKD) platform on the live network of the dynamic test ranges at PXE Chandipur, Odisha.
- The platform was developed under DRDO’s Microelectronic Devices, Computational Systems and Cyber Security (MCC) cluster, with Taqbit Labs, Bengaluru as the production partner.
- It is meant to protect real-time observations and telemetry from artillery and armoured weapon trials, where data can reveal a weapon’s actual performance and weaknesses.
- PXE Chandipur was established on 7 November 1895 and became a DRDO establishment in October 1958, making it the oldest establishment in the organisation.
- In July 2026, DRDO and Taqbit Labs completed military field trials of a fibre-based QKD system over 100 km between Prayagraj and Vindhyachal, with a 6 per cent QBER and a secure key rate of about 5 kbps.
- QKD uses quantum physics to detect eavesdropping, while post-quantum cryptography uses mathematics and runs on existing networks; the two approaches are complementary.
- The National Quantum Mission, approved on 19 April 2023 with an outlay of ₹6,003.65 crore, is implemented by DST and targets satellite-based quantum communication over 2,000 km.
