SECURE COMMUNICATION SYSTEM COMPRISING TERMINALS WITH DIFFERENT SECURITY CAPABILITY LEVELS

摘要

A communication system (100) including a group management processor (144) operable to divide an enlarged group of user terminals formed by patching of smaller groups into sub-sets of user terminals including: (1) an encrypted sub-set of terminals (103, 113, 123) which are operable to undertake only encrypted communications; and (2) a selectable-clear sub-set of terminals (105, 115, 125) which includes: (i) selectable terminals that are able to undertake clear communications and, when selected, encrypted communications; and (ii) clear terminals that are operable to undertake only clear communications; and a translator (143) operable to translate a communication sent in a first encrypted form from a user terminal (103) of one of the sub-sets into the second encrypted form suitable for decryption by user terminals (105, 115) of the other sub-set. Also described is a method (300) and a processor (144) for use in the system.