1. A wireless communication terminal, the terminal comprising:a transceiver; and
wherein the processor is configured to:
receive, through the transceiver, a trigger frame from a base wireless communication terminal with which the terminal is not associated, wherein the trigger frame triggers a multi-user uplink transmission,
perform an uplink transmission in response to the trigger frame when the trigger frame allocates one or more random access resource units indicated by a temporary association identifier (AID), wherein the uplink transmission is performed through at least one of the random access resource units indicated by the temporary AID, and
receive, through the transceiver, an ACK frame for the uplink transmission,
wherein ACK information for the terminal is identified from the ACK frame based on the temporary AID, and
wherein the temporary AID is an AID not included in a set of AIDs for AID assignment of each terminal in a basic service set (BSS) and has a value different from any AID included in the set of AIDs for AID assignment.