A handover method, wherein the method comprises: sending, by a mobile node, MN, first instruction information to a new access router, NAR, by using a previous access router, PAR, wherein the first instruction information is used to instruct the NAR to construct a care-of test initialization message and send the care-of test initialization message to a corresponding node, CN, and the care-of test initialization message comprises a new care-of address, NCoA of the MN and is used to request a care-of keygen token from the CN based on the NCoA; handing over the MN from the PAR to the NAR; receiving, by the MN, the care-of keygen token sent by the NAR from the CN; and binding the MN with the CN based on the care-of keygen token; wherein before the handing over the MN from the PAR to the NAR, the method further comprises: obtaining, by the MN, a home address, HoA, authentication parameter; and the binding the MN with the CN based on the care-of keygen token comprises: binding the MN with the CN based on the care-of keygen token and the HoA authentication parameter; wherein the obtaining, by the MN, an HoA authentication parameter comprises: if the MN locally stores a permanent home keygen token, locally obtaining, by the MN, the permanent home keygen token; and if the MN does not locally store the permanent home keygen token, but stores a Cryptographically Generated Address, CGA, parameter and a CGA signature, locally obtaining, by the MN, a Cryptographically Generated Address, CGA attribute of an HoA, wherein the CGA attribute of the HoA comprises a CGA parameter and a CGA signature; and if the MN does not locally store the permanent home keygen token and the HoA is not a CGA attribute of the HoA, determining that the MN did not communicate with the CN before and sending, by the MN, a home test initialization message to the CN by using a home agent, and receiving a home test message sent by the home agent from the CN, wherein the home test message comprises a home keygen token. sending, by a mobile node, MN, first instruction information to a new access router, NAR, by using a previous access router, PAR, wherein the first instruction information is used to instruct the NAR to construct a care-of test initialization message and send the care-of test initialization message to a corresponding node, CN, and the care-of test initialization message comprises a new care-of address, NCoA of the MN and is used to request a care-of keygen token from the CN based on the NCoA; handing over the MN from the PAR to the NAR; receiving, by the MN, the care-of keygen token sent by the NAR from the CN; and binding the MN with the CN based on the care-of keygen token; wherein before the handing over the MN from the PAR to the NAR, the method further comprises: obtaining, by the MN, a home address, HoA, authentication parameter; and the binding the MN with the CN based on the care-of keygen token comprises: binding the MN with the CN based on the care-of keygen token and the HoA authentication parameter; wherein the obtaining, by the MN, an HoA authentication parameter comprises: if the MN locally stores a permanent home keygen token, locally obtaining, by the MN, the permanent home keygen token; and if the MN does not locally store the permanent home keygen token, but stores a Cryptographically Generated Address, CGA, parameter and a CGA signature, locally obtaining, by the MN, a Cryptographically Generated Address, CGA attribute of an HoA, wherein the CGA attribute of the HoA comprises a CGA parameter and a CGA signature; and if the MN does not locally store the permanent home keygen token and the HoA is not a CGA attribute of the HoA, determining that the MN did not communicate with the CN before and sending, by the MN, a home test initialization message to the CN by using a home agent, and receiving a home test message sent by the home agent from the CN, wherein the home test message comprises a home keygen token. binding the MN with the CN based on the care-of keygen token and the HoA authentication parameter; wherein the obtaining, by the MN, an HoA authentication parameter comprises: if the MN locally stores a permanent home keygen token, locally obtaining, by the MN, the permanent home keygen token; and if the MN does not locally store the permanent home keygen token, but stores a Cryptographically Generated Address, CGA, parameter and a CGA signature, locally obtaining, by the MN, a Cryptographically Generated Address, CGA attribute of an HoA, wherein the CGA attribute of the HoA comprises a CGA parameter and a CGA signature; and if the MN locally stores a permanent home keygen token, locally obtaining, by the MN, the permanent home keygen token; and if the MN does not locally store the permanent home keygen token, but stores a Cryptographically Generated Address, CGA, parameter and a CGA signature, locally obtaining, by the MN, a Cryptographically Generated Address, CGA attribute of an HoA, wherein the CGA attribute of the HoA comprises a CGA parameter and a CGA signature; and if the MN does not locally store the permanent home keygen token and the HoA is not a CGA attribute of the HoA, determining that the MN did not communicate with the CN before and sending, by the MN, a home test initialization message to the CN by using a home agent, and receiving a home test message sent by the home agent from the CN, wherein the home test message comprises a home keygen token.