U.S.Patent Apr.9,2019 Sheet 7 of 10 US10,257,802B2 1401 A MAG receives an L2 attach request message sent by an MN 1402 The MAG adds the L2 attach request message to a bearer message,and forwards the bearer message to an SDN controller 1403 The MAG receives a message that is sent by the SDN controller and for establishing a tunnel between the MAG and an LMA,and completes establishment of the tunnel on the MAG side according to the message for establishing a tunnel between the MAG and the LMA 1404 The MAG receives a message that is sent by the SDN controller and for adjusting a flow entry of the MN,and adjusts,according to the message for adjusting a flow entry of the MN,a flow entry that is of the MN and stored in the MAG 1405 If establishment of the tunnel between the MAG and the LMA succeeds, the MAG forwards an RA message received from the SDN controller to the MN,so that the MN is registered with a network FIG.14Apr . 9 , 2019 Sheet 7 of 10 US 10 , 257 , 802 B2 1401 A MAG receives an L2 attach request message sent by an MN 1402 The MAG adds the L2 attach request message to a bearer message , and forwards the bearer message to an SDN controller 1403 The MAG receives a message that is sent by the SDN controller and for establishing a tunnel between the MAG and an LMA , and completes establishment of the tunnel on the MAG side according to the message for establishing a tunnel between the MAG and the LMA 1404 The MAG receives a message that is sent by the SDN controller and for adjusting a flow entry of the MN , and adjusts , according to the message for adjusting a flow entry of the MN , a flow entry that is of the MN and stored in the MAG 1405 If establishment of the tunnel between the MAG and the LMA succeeds , the MAG forwards an RA message received from the SDN controller to the MN , so that the MN is registered with a network FIG . 14