Are You Ready to Witness the Future of Data Security?
Platform
©2025 QuNu Labs Private Limited, All Rights Reserved.
Quantum key distribution works over single fiber spans - typically under 100km for practical systems, maybe 300km maximum with advanced technology. To connect cities 1000km apart, or create a national quantum network, you need trusted nodes - intermediate points that receive quantum keys from neighbors and forward them onward. Alice QKDs to Node X, Node X stores the key securely in an HSM, Node X QKDs to Bob using a different key, then Node X XORs Alice's data with both keys so Bob can decrypt. The "trusted" part is crucial - Node X temporarily has access to the key, so it must be physically and operationally secure. Think military base, hardened data center, or government facility. Critics argue trusted nodes weaken QKD's unconditional security by introducing trust assumptions. Proponents counter that trusted nodes are the only practical way to build quantum networks with today's technology. The alternative - quantum repeaters that amplify quantum signals without measuring them - requires technologies not yet mature. China's Beijing-Shanghai quantum network uses 32 trusted nodes over 2000km. Most practical QKDNs use trusted node architecture because it works now.
Point-to-point QKD serves research labs. Networks serve countries. Trusted nodes are the pragmatic solution that enables metropolitan, regional, and national quantum networks today rather than waiting decades for quantum repeaters. They trade pure unconditional security for deployable practical security, which is still vastly better than public-key cryptography facing quantum threats.
For governments building national quantum infrastructure, telecom operators deploying metro quantum networks, or smart cities connecting distributed systems, trusted node architecture provides the practical path to implementation. With proper physical security and HSM-based key storage, trusted nodes provide security far beyond classical alternatives while enabling networks that span realistic distances and topologies.
Metropolitan quantum networks spanning cities 50-500km, national quantum backbones connecting regions over 1000+ km, smart city infrastructure connecting distributed sensors and controllers, financial district networks interconnecting banks and trading firms, government agency networks requiring secure regional communications
https://www.qnulabs.com/quantum-key-distribution | https://www.qnulabs.com/blog/
trusted nodes, quantum network nodes, QKD trusted node, quantum relay, key forwarding node, secure quantum node, QKDN architecture, metro quantum network, national quantum network infrastructure, HSM key storage, quantum network routing