Jing Yan Haw

We present the strategic framework and technical foundations behind the development of the National Quantum-Safe Network (NQSN) in Singapore—a resilient, fully interoperable quantum-safe network. The testbed features a star-topology architecture built on production-grade fiber infrastructure, supporting multi-protocol quantum key distribution (QKD) and diverse applications from multiple vendors. A centralised key and network management system underpins its interoperability, enabling seamless integration across technologies. We further explore a range of quantum-secured use cases, including data center connectivity, edge computing, hybrid QKD–post-quantum cryptography (PQC) encryption, and multi-layer integration within the OSI stack. These technical insights demonstrate the feasibility and flexibility of deploying quantum-safe capabilities in a multi-input, multi-output network environment.

The National Quantum-Safe Network (NQSN) in Singapore is a nationwide collaborative platform and a field-deployed test-bed aimed at demonstrating quantum-safe cryptography solutions. NQSN links up academic, public and private members, targets trials for quantum key distribution (QKD) network with different QKD protocols, post-quantum cryptography (PQC) and classical symmetric key technologies.

Quantum physics provides some natural ways to generate genuine randomness, however, the generation of certifiable randomness still meets various theoretical and technical challenges. Recently, a work on a source device independent protocol was proposed, where the measurement apparatus is fully trusted and no assumption about the incoming light source is made. Here, we experimentally implement and verify a source device independent quantum random number generator (SDI-QRNG), built with off-the-shelf optical and electronic components. Furthermore, a series of quantum attacks were performed to evaluate the security and implementation vulnerability of the SDI-QRNG.