METHOD OF DISTRIBUTING AND UTILIZING ENCIPHERING KEYS

摘要

PHN 10.652 02.02.1984 "Method of distributing and utilizing enciphering keys". In a communication network with cryptographically protected connections a unique key is used for each connection between two subscribers, so that when one or more keys fall into the hands of an unauthorized person it has no consequences for the protection of the remaining connections. In a network comprising N subscribers -this implies that each participant must have N-1 keys for communication with the other participants. Such a set of N-1 keys is obtained by putting a column from a NxN key matrix (main diagonal empty) at the disposal of each participant. During the connection set-up the correct unique key is automatically selected by interchange of the column number. The key matrices used in the network can be regularly replaced without it being necessary to interrupt the operation of the network.