METHOD AND APPARATUS FOR STATE TRANSITION OF DEVICE-TO-DEVICE COMMUNICATIONS

摘要

Disclosed are a method and an apparatus for state transition of device-to-device (D2D) communications. The method according to the present invention comprises the following steps: determining whether D2D initiation is required while a terminal is operating in a first or second state defined by EMM-Deregistered and ECM-IDLE at a non-access stratum (NAS) layer, including RRC-IDLE; if the D2D initiation is required, transitioning to a third state including EMM-Registered and ECM/RRC-Connected and performing the D2D initiation through a mobile communications network; if a deactivation condition is satisfied or a D2D state update is completed in the third state, transiting a fourth state including EMM-Registered and ECM/RRC-IDLE; and if a state update or scheduling for D2D communications is required in the fourth state, transiting to the third state.