METHOD FOR KEY MANAGEMENT OF POINT-TO-POINT COMMUNICATIONS.

摘要

A method of secure key distribution in a communication system having a plurality of subscriber units and an infrastructure communication center is provided. A first subscriber unit sends a request to the infrastructure communication center for a secure communication link with a second subscriber unit. This request includes an encrypted session encryption key which was encrypted with a first subscriber registration key. The infrastructure communication center decrypts the encrypted session encryption key with the first subscriber registration key. Subsequently, the infrastructure communication center re-encrypts the session encryption key with a second subscriber registration key. This re-encrypted session encryption key is sent to the second subscriber unit. In an alternative method, the first subscriber unit and the infrastructure communication center a priori know a session key. Therefore, the infrastructure communication center only needs to encrypt and send the session encryption key to the second subscriber unit, in response to a request by the first subscriber unit.