A handover authentication method includes performing, by a wireless network server, a first authentication between a client and the wireless network server via a first network gateway; obtaining first authentication keys for the wireless network server and the client based on the first authentication; determining, by the wireless network server, a need to handover the client from the first network gateway to a second network gateway; deriving, by the wireless network server and from the first authentication keys, a handover authentication key shared by the client and the wireless network server; obtaining, by the wireless network server, second authentication keys for the network server and the client; and serving, by the wireless network server, the client via the second network gateway.