Methods and systems are provided for distributing key information by securely transmitting light information in a network along a path comprised of a plurality of network devices and by using a key distribution center (KDC) connected with the network. Three or more user devices connected with the network...http://www.google.de/patents/US7457416?utm_source=gb-gplus-sharePatent US7457416 - Key distribution center for quantum cryptographic key distribution networks
