KT Corp. said Tuesday it has developed Korea’s fastest quantum key distribution system, capable of generating 300,000 encryption keys per second — twice the rate of its previous model and a major step forward in domestic quantum communication technology.
QKD systems rely on the principles of quantum mechanics to produce encryption keys that cannot be duplicated, effectively blocking eavesdropping attempts on physical communication lines.
“This is the fastest QKD system developed using domestic technology,” a KT official said. “Once deployed, it can supply quantum keys to more than 70,000 encryption devices every minute.”
KT introduced a QKD model operating at 150,000 keys per second in May 2024. Less than two years later, the company has doubled that figure — a notable pace in a field where improving performance often comes at the cost of stability.
Single photons — the smallest unit of light — lie at the core of QKD technology. They are highly sensitive to dispersion and scattering, meaning even minor disturbances can cause quantum states to collapse and disrupt encryption processes.
To address this, KT developed an error-reduction filter and a timing control system designed to manage photon generation and detection. By cutting noise and improving synchronization, the system achieved faster key generation while maintaining stable operation.
Lee Jong-sik, head of KT’s network R&D lab, said the company plans to continue advancing its in-house quantum communication capabilities and broaden technology transfer efforts.
“Based on sustained development and transfer of our quantum technologies, we will contribute to the growth of the domestic quantum industry,” Lee said. “We will also continue efforts to secure future quantum internet technologies.”
yeeun@heraldcorp.com
