Anchor gateway switching method, apparatus, and system

An anchor gateway switching method, comprising:

• receiving, by a software-defined networking (SDN) controller, a modification request message from a control plane (CP) device, wherein the modification request message comprises an identifier of a terminal and an identifier of a target anchor gateway;
• updating, by the SDN controller based on the identifier of the terminal and the identifier of the target anchor gateway, a forwarding flow table corresponding to a downlink packet of the terminal;
• and
• sending, by the SDN controller, an updated forwarding flow table to an SDN switch.

An anchor gateway switching method, comprising:

• receiving, by a software-defined networking (SDN) switch, a forwarding flow table corresponding to a first end packet from an SDN controller, wherein the first end packet is used to trigger a source anchor gateway to send a second end packet, and the forwarding flow table comprises an end marker;
• generating, by the SDN switch after receiving a first downlink packet of a terminal, the first end packet based on the first downlink packet and the end marker, wherein the first downlink packet is a downlink packet from a service server to the terminal for the first time after the source anchor gateway is switched to a target anchor gateway;
• and
• forwarding, by the SDN switch, the first end packet to the source anchor gateway based on the forwarding flow table, to trigger the source anchor gateway to send the second end packet.