Technology

as I recall they do use entanglement

Quantum communication relies on quantum key distribution (QKD) which is a form of encryption based on quantum mechanics. Photons are encoded with quantum states to create a cryptographic key. These keys are shared between parties via fiber-optic networks or satellites. Since quantum states cannot be copied without altering them, any eavesdropping attempt disrupts the photon’s state. Any tampering collapses the link, exposing intrusion.

Unlike classical encryption, QKD's security is rooted in physics laws, making it immune to brute-force attacks. China currently has the world's largest QKD network and satellite-to-ground links that ensure secure communication for the government and the military.