A SECONDARY BASE STATION APPARATUS, A COMMUNICATION METHOD FOR A SECONDARY BASE STATION APPARATUS, A MASTER BASE STATION APPARATUS, A COMMUNICATION METHOD FOR A MASTER BASE STATION APPARATUS, A MOBILE TERMINAL APPARATUS, A COMMUNICATION METHOD FOR A MOBILE TERMINAL APPARATUS, AND AN INTEGRATED CIRCUIT

摘要

The present invention relates to a method for establishing a secure communication link between a mobile station and a secondary base station in a mobile communication system. The present invention also provides a mobile communication system for performing such a method, and a computer readable medium, wherein instructions in the computer readable medium cause the mobile communication system to perform the method described herein. Specifically, the present invention provides that, in response to a detected or signaled potential security intrusion, the master base station increments a freshness counter for re-initiating communication between the mobile station and the secondary base station, and the mobile station and the secondary base station facilitate communication between them. Reinitialization is suggested. Reinitialization is performed under the control of the master base station and includes deriving the same security key based on the incremented freshness counter, and establishing a secure communication link using the derived same security key.