SYNCHRONIZATION METHOD AND SYSTEM FOR COUNTERS OF INTEGRITY SECURITY OF SRB3 AND SRB4

摘要

A synchronization method for Counters of Integrity security (COUNT-I) of Signaling Radio Bearer (SRB) 3 and SRB4 during relocation, which includes the following steps: after a Target Radio Network Controller (TRNC) receives a hard handover accomplishment message, both the TRNC and a User Equipment (UE) use a START value of the latest configured Core Network (CN) domain to update the highest N valid bits of the uplink and downlink Hyper Frame Numbers (HFNs) of SRB3 and SRB4, set other bits of HFNs as zero, and update the uplink and downlink Sequence Numbers (SNs) of SRB3 and SRB4 with zero. A synchronization system for COUNT-Is of SRB3 and SRB4 during relocation is also disclosed in the present invention, and with the method and system of the present invention, after a Serving Radio Network Subsystem (SRNS) relocation succeeds the synchronization of COUNT-Is of SRB3 and SRB4 maintained by the UE and the TRNC can be achieved.