he group of Jianwei PAN at the University of Science and Technology of China (USTC) of CAS, have sent secure quantum protocol, known as measurement-device-independent quantum key distribution (MDIQKD), over a distance of 404 km. Compared with earlier experiments, they demonstrated a 500-fold increase in speed, reaching a key-distribution rate that would be sufficient to ensure encrypted voice transmission by telephone.
CAS news release, November 11, 2016
Group at USTC sets world distance record of 404 km for secure quantum communication