In one implementation, a NAS layer (202) of a radio terminal (1) obtains, from an AS layer (208) of the radio terminal (1), either or both of: information regarding one or more access barring categories (401) broadcasted by a serving network (2); and the number of the one or more access barring categories. If barring information corresponding to a first access barring category (404) to which an application that triggers a session establishment (403) belongs is not broadcasted by an eNB (2), the NAS layer (202) replaces the first access barring category (404) with a particular access barring category among the one or more access barring categories (401) broadcasted by the serving network (202).