Abstract: A method for providing a security mechanism to an Asynchronous Transfer Mode (ATM) emulated local-area network (LAN) is disclosed. The ATM emulated LAN is served by a LAN Emulation Server (LES), a Broadcast and Unknown Server (BUS), and a LAN Emulation Configuration Server (LECS). After receiving a LE_JOIN_REQUEST from an LE client within the emulated LAN, the LES forms a LE_CONFIGURE_REQUEST on behalf of the LE client, by utilizing the information from the LE_JOIN_REQUEST. The LES then sends the LE_CONFIGURE_REQUEST to the LECS. In turn, the LECS sends back a LE_CONFIGURE_RESPONSE to the LES. After receiving the LE_CONFIGURE_RESPONSE from the LECS, a determination is made as to whether or not a status field within the LE_CONFIGURE_RESPONSE indicates a success and a target ATM address field within the LE_CONFIGURE_RESPONSE contains an ATM address of the LES.