Base stations and methods

PROBLEM TO BE SOLVED: To provide a mobile communication method, a radio terminal, and a base station that can prevent a network from making erroneous parameter adjustment.SOLUTION: A base station transmits a transmission request for a radio link fault report to a radio terminal. The base station receives the radio link fault report including first time information for identifying time a connection fault of a radio link occurred from the radio terminal. The base station also receives connection establishment failure information including second time information for identifying time establishment of RRC connection was failed from the radio terminal.SELECTED DRAWING: Figure 4