Industry · Early Pilots
Quantum Computing for Telecommunications
Telecom carriers are exploring quantum key distribution for secure links and quantum-inspired optimization for network routing, while also building toward a future quantum internet.
Maturity
Early pilots; QKD networks deployed, post-quantum migration beginning
Most mature quantum technology
Quantum key distribution links and quantum random number generators
Long-term goal
Quantum internet with repeaters and entanglement distribution
Hardware needed
Single-photon sources and detectors, quantum memories, and fiber or satellite links
Strongest alternative
Post-quantum cryptography on ordinary hardware, favored by many agencies
Realistic horizon
Secure links now; entanglement networks over the 2030s
Overview
Telecommunications is where quantum computing and quantum communication meet. Carriers run the networks that carry the world's data, so they face the security threat that quantum computers pose to encryption, and they are natural builders of the quantum networks that may link future quantum machines. They also run enormous optimization problems, from placing radio towers to routing traffic, and some carriers invest in quantum computing as customers.
This page separates three threads. Security, meaning post-quantum cryptography and quantum key distribution, is the most active. Quantum networking, the long-term plan to distribute entanglement between sites, is a research frontier with real prototypes. And network optimization with quantum computers is a set of pilots with the same mixed results as in other industries.
Why this industry is a candidate for quantum computing
Telecom networks protect traffic with public-key cryptography, so they are exposed to the same Shor's algorithm threat as banks, but with a twist: their equipment, from base stations to subscriber SIM cards, has long lifetimes and is hard to update. A standards body for mobile networks has therefore been working on post-quantum migration paths.
Quantum communication is also native to telecom. Single photons travel through optical fiber and free space, the same media carriers already operate, so the industry is the natural home for quantum key distribution links and for networks that distribute entanglement to connect quantum computers and sensors.
Key facts and numbers
| Item | Detail |
|---|---|
| China QKD backbone | More than 2,000 km between Beijing and Shanghai, operating since 2017 |
| Micius satellite | Launched in 2016, with satellite-to-ground QKD and entanglement distribution over about 1,200 km |
| Fiber QKD range | A few hundred kilometers without trusted nodes or repeaters; laboratory twin-field experiments reach about 1,000 km at very low rates |
| QuTech Delft | Three-node entanglement network demonstrated in 2021 |
| Harvard and AWS | Entanglement between memories over about 35 km of Boston fiber (2024) |
| Post-quantum overhead | ML-KEM-768 public keys are about 37 times larger than X25519 keys |
Where quantum computing could help
Quantum key distribution networks
The problem: Operators of critical links, such as between data centers or government sites, want key exchange whose security does not depend on computational assumptions.
The quantum approach: Quantum key distribution sends single photons over fiber or through free space and detects eavesdropping from the disturbance it causes. Trusted-node networks relay keys over long distances.
Where things stand: China operates a backbone of more than 2,000 kilometers between Beijing and Shanghai and has demonstrated satellite links over 1,000 kilometers. In Europe, the EuroQCI initiative is building national and cross-border networks, and BT and Toshiba have trialed a QKD network in London. Agencies such as the U.S. NSA and the UK NCSC nonetheless recommend post-quantum cryptography over QKD for most uses.
Related algorithms: BB84 Quantum Key Distribution, E91 Quantum Key Distribution, Device-Independent Quantum Key Distribution
Post-quantum security for mobile and fixed networks
The problem: Mobile networks rely on cryptography in SIM cards, radio access, the core network, and backhaul, and fixed networks use it in VPNs and routing security. Replacing it across billions of devices takes years.
The quantum approach: Adopt NIST-standardized algorithms such as ML-KEM and ML-DSA, deploy hybrid modes, and plan upgrades to SIM and network functions, guided by industry bodies such as the GSMA.
Where things stand: Work is under way in standards groups, and large carriers have begun trials. The main challenge is the long life of deployed hardware and the larger size of post-quantum keys and signatures.
Related algorithms: Shor's Algorithm, Quantum Digital Signatures
The quantum internet
The problem: Linking quantum computers, sensors, and clocks over distance needs a network that can distribute entanglement, which cannot be amplified like classical signals.
The quantum approach: Quantum repeaters use memories and entanglement swapping to extend range. Teleportation moves quantum states between nodes. Satellites provide long links.
Where things stand: Research prototypes exist: a three-node entanglement network at QuTech in Delft in 2021, a Harvard and Amazon fiber network connecting memories across about 35 kilometers in Boston in 2024, and Chinese satellite experiments. EPB in Chattanooga operates a commercial quantum network. A global quantum internet is a decades-long project.
Related algorithms: Quantum Teleportation Protocol, E91 Quantum Key Distribution, Quantum Secret Sharing
Network design and optimization
The problem: Carriers must place towers, assign frequencies, route traffic, and plan capacity, all with many constraints and uncertain demand.
The quantum approach: These problems are formulated as optimization and tested on annealers and QAOA, and quantum machine learning has been proposed for tasks such as channel estimation.
Where things stand: Pilots with carriers and vendors have solved small instances. Classical optimization is strong and mature in this industry, and no quantum advantage has been shown.
Related algorithms: Quantum Approximate Optimization Algorithm (QAOA), Quantum Annealing, Max-Cut with Quantum Algorithms (QAOA and Quantum Max-Cut)
Who is working on it
- BT and Toshiba, with HSBC as a user, on a commercial-scale QKD network trial in London.
- The European Union's EuroQCI program and national carriers building quantum communication infrastructure, with satellite components planned.
- China Telecom Quantum Group and the Chinese Academy of Sciences, operating a large QKD backbone and satellite links.
- SK Telecom and ID Quantique, which has been owned in part by SK Telecom and is now majority-owned by IonQ, on QKD and quantum random number generators in phones and networks.
- EPB in Chattanooga, operating a commercial quantum network with IonQ technology, and research groups at QuTech, Harvard, and Caltech on repeaters.
Realistic timeline
| Horizon | What to expect |
|---|---|
| Now to 2030 | Post-quantum migration plans and trials, QKD in niche government and financial links, and quantum random number generators in devices. |
| 2030 to 2035 | Vulnerable algorithms are retired in many standards. Early quantum repeaters link nearby sites for sensing and computing experiments. |
| 2035 and later | If repeaters mature, regional entanglement networks could connect quantum computers and clocks. A global quantum internet remains a long-term goal. |
How to judge quantum claims in this sector
In telecommunications, the most common confusion is between quantum key distribution and post-quantum cryptography, which are different tools for different threats. QKD gives information-theoretic key exchange over a dedicated optical link but needs special hardware and authentication, and it does not protect other layers of the network. Post-quantum cryptography is software that protects existing protocols and scales to every device.
When a carrier announces a quantum network, check what it actually delivers: a key-distribution link between two sites, a trusted-node chain, or genuine entanglement distribution. The first two are deployable today with known limits. The third is an experiment. Also check whether the same security could be achieved with post-quantum algorithms at lower cost, which is the question that agencies such as the NSA and NCSC ask.
What stands in the way
- Distance and loss: photons cannot be amplified, so range needs trusted nodes or repeaters that are still immature.
- Cost and interoperability: QKD hardware is specialized and standards are still maturing.
- Legacy equipment: SIMs and base stations have long lives and limited upgrade paths.
- Policy: agencies favor post-quantum cryptography, which affects the business case for QKD.
What organizations in this sector should do now
- Plan the post-quantum migration of core network, VPN, signing, and subscriber systems with vendor roadmaps.
- Evaluate QKD only for specific high-assurance links, and understand its limits.
- Participate in standards bodies and testbeds to shape interoperability.
- Track quantum repeater and memory progress for future network services.
Myths versus reality
- Myth: QKD makes networks unhackable. Reality: it protects key exchange, and implementations have side-channel risks.
- Myth: a quantum internet exists. Reality: prototypes exist, but they are small and experimental.
- Myth: quantum computers will fix network congestion. Reality: classical optimization is strong, and quantum advantage is unproven.
The bottom line
Telecom will remain at the center of quantum security and networking, because the industry owns the fiber and the customers. Today's priority is migrating cryptography. The quantum internet is a long-term research goal, and operators can participate through testbeds and standards without large commitments.
Frequently asked questions
What is quantum key distribution?
A method for two parties to create shared secret keys using single photons, with eavesdropping revealed by disturbance to the quantum states.
Is QKD or post-quantum cryptography better?
They address different threat models. Most government agencies recommend post-quantum cryptography for general use because it runs on existing hardware, with QKD for specific high-assurance links.
What is a quantum repeater?
A device that extends the range of entanglement distribution using quantum memories and entanglement swapping, because photons cannot be amplified.
Do carriers use quantum computers?
Some run pilots for network optimization, but production networks use classical optimization.
What is the status of the quantum internet?
There are small prototypes, such as networks in Delft and Boston and the commercial EPB network in Chattanooga, but a large-scale quantum internet is a long-term effort.
Keep exploring
- Algorithm: BB84 Quantum Key Distribution
- Algorithm: E91 Quantum Key Distribution
- Algorithm: Quantum Teleportation Protocol
- Algorithm: Shor's Algorithm
- Hardware: IonQ Forte (and Forte Enterprise)
- Company: IonQ
- Company: Q-CTRL
- Company: Quantum Computing Inc. (QCi)
- Research: Prototype Quantum Repeater Demonstrates Entanglement Distribution Over Extended Fiber Distance
- Research: Case Study: Post-Quantum Cryptography Migration in a Large Financial Institution
- Industry: Quantum Computing for Cybersecurity
- Industry: Quantum Computing and the Public Sector
- Industry: Quantum Technology for Space and National Security
- Industry: Quantum Computing for Finance
This page is written for educational purposes and summarizes public announcements, published research, and published resource estimates (last reviewed September 30, 2026). Vendor and customer claims have not all been independently verified, timelines are estimates, and nothing here is investment or business advice.