Patent ID: 7738867

Claim:
A method of processing a message received at a user equipment (UE), the UE configured for use in a UMTS, Universal Mobile Telecommunications System, communications system, wherein the message includes a Ciphering Mode Info information element and is one of a plurality of message types comprising a Radio Bearer Setup message, a Radio Bearer Reconfiguration message, a Radio Bearer Release message, a Transport Channel Reconfiguration message, a Physical Channel Reconfiguration message, a Cell Update Confirm message, a URA, UTRAN Registration Area, Update Confirm message and a UTRAN, Universal Terrestrial Radio Access Network, Mobility Information message, the method comprising: determining whether a Ciphering Activation Time for DPCH, Dedicated Physical Channel, information element that identifies a ciphering activation time is present in the message when radio bearers exist using radio link control (RLC) transparent mode (TM); and in the event that the Ciphering Activation Time for DPCH information element is not present, refraining from acting on the message and returning a message with an error return value indicating the absence of the information element.