Patent ID: 6173174
Filing Date: 2001-01-09
Classification: H04W

Abstract:
A method for sending an updated Authentication-Key (A-Key) value in a cellular telephone system, comprising the steps, performed by a processor of an Authentication Center (AC) portion of the system, of:finding that an authentication with a first A-Key has failed for a handset in the system;determining whether the system is configured to allow automated A-Key updating for the Mobile Switching Center/Vistor Location Register (MSC/VLR) associated with the handset;obtaining an alternate A-Key value if the result of the determining step is true;generating Shared Secret Data (SSD) using the alternate A-Key if the result of the determining step is true; andperforming an SSD update by sending an SSD update message to the MSC/VLR associated with the handset if the result of the determining step is true.