A communication system, a UE (User Equipment), a communication method and a computer readable medium may be provided. The communication system (100) includes: a first UE (User Equipment) (110) including a first controller and a first transceiver, wherein the first controller is configured to control the transceiver to send a message including L2 ID (Layer 2 Identity) and verification information; and a second UE (120) including a second controller and a second transceiver, wherein the second controller is configured: to control the transceiver to receive the message from the first UE (110); and to determine whether to accept the L2 ID or not using the verification information.