| 摘要 |
A wireless communication system has a mobile unit, a UTRAN, and a plurality of established radio bearers. The UTRAN is used for transmitting a first control command to the mobile unit, and the first control command is used for triggering establishment of a new radio bearer between the mobile unit and the UTRAN. Each established radio bearer between the mobile unit and the UTRAN has a corresponding first HFN, which are used for ciphering. The mobile unit generates a first value based on the first HFNs of established radio bearers wherein the first value is at least as great as the x most significant bits (MSBx) of each first HFN. Each of the mobile unit and the UTRAN sets MSBx of an initial HFN associated with the new radio bearer equal to the first value, regardless of whether or not the ciphering is "STARTED" or "NOT STARTED".
|
