METHODS, APPARATUS AND SYSTEMS USING VEHICLE-TO-EVERYTHING (V2X) ENHANCEMENTS TO SUPPORT VEHICLE-TO- PEDESTRIAN (V2P) COMMUNICATION

V2X Enhancements to support V2P communication are disclosed. In particular, Vehicle to Pedestrian Communications are provided. Methods and apparatus for operation by an initiating wireless transmit/receive unit (WTRU) for direct link with a peer WTRU using a first key identifier of a root key are provided. In one embodiment, a method includes sending, by the initiating WTRU to the peer WTRU, a release request message to release the direct link with the peer WTRU, the release request message including information indicating first security information associated with a second key identifier of the root key. The method further includes receiving, receiving, by the initiating WTRU from the peer WTRU, a response to the release request message including second security information associated with the second key identifier of the root key. The method also includes determining, by the initiating WTRU, the second key identifier of the root key using the first security information and the second security information; and sending, by the initiating WTRU to the peer WTRU, a message including information indicating the second key identifier of the root key.