DATA COMMUNICATION SECURITY ARRANGEMENT AND METHOD

摘要

The present invention relates to a method and arragement for synchronization of a communication session for encrypted transmission or authentication between at least two communicating units, a first unit and a second unit communicating via a communication channel. Each unit comprises a session counter (X, Y). The method comprises a handshake procedure whereby the synchronization of session counters is obtained by successively communicated signatures between said communicating units.