The details of an apparatus and method of handling simultaneous universal
terrestrial radio access network radio resource control procedures which
change the security configuration in a universal mobile
telecommunications system user equipment are disclosed herein. According
to one aspect of the present application, there is provided a user
equipment apparatus having a message handler, a sequential processor, a
command store, and a security configuration change detector, wherein said
message handler is coupled to said command store, is coupled to said
sequential processor, and is coupled to said security configuration
change detector to save, process, and detect configuration changes in
commands respectively, and to determine if there is an existing command
at the user equipment, such that the user equipment appears to the UTRAN
as though it were processing commands simultaneously. According to
another aspect, there is provided a method of processing simultaneous
commands at a user equipment having a security configuration, including
the steps of: determining if there is an existing command at the user
equipment; upon reception of a received command: suspending the existing
command processing; determining if commands contain a security
configuration change; and either rejecting the received command; or
saving the received command prior to resuming the existing command; such
that the user equipment appears to the UTRAN to be processing commands
simultaneously.