METHOD OF UPDATING MULTICAST/BROADCAST SERVICE KEY INFORMATION

摘要

PURPOSE: A method of updating multicast/broadcast service key information is provided to supply a MBS(Multimedia Broadcasting Service) even if a terminal is out of an idle mode by transmitting update MBS key information efficiently to a terminal in idle mode. CONSTITUTION: In a device, a message is received from a base station in an idle mode(S301). The message includes updated MBS key information showing which kind of the MBS key is updated. An MBS service is provided from the base station by using the MBS key information updated in the normal mode state(S302). The updated MBS key information comprises more than one among the updated group code key information and the updated group traffic code key information. The updated group code key is generated all base stations within the MBS domain equally.