Hierarchical key management system.

摘要

A hierarchical key management system includes a number of secure terminals (1-500). These terminals provide secure access to a corresponding number of users (1-500). A user inserts a security activation device (SAD) or key into the secure terminal to access a secure connection through the established communication network (PSTN). A group of secure wireline terminals (1-500) is connected to a key certification authority (KCA). There may be several groups of key certification authorities (A,B,C) and corresponding secure terminal users (1-500). At the highest level, a key certification center (KCC) authorizes secure communications by the key certification authorities (KCA). In turn, the key certification authorities (KCA) authorize secure communications between the users. As a result, if one level of key management is compromised, other levels and users are not affected.