Patent ID: 8887251

Claim:
A handover method for a mobile terminal between heterogeneous networks, comprising: receiving, by the mobile terminal and via a source network, a packet from a device of the source network, a payload of the packet including information on at least one target authenticator of at least one target network from a source authenticator of the source network, the information including a respective Internet Protocol (IP) address of the at least one target authenticator of the at least one target network which is selectable by the mobile terminal for performing a handover; transmitting, by the mobile terminal and via the source network, a pre-authentication start request message to a target authenticator selected, by the mobile terminal, from among at least one target authenticators of target networks which are selectable by the mobile terminal for performing a handover using the IP address of the target authenticator; receiving, by the mobile terminal and via the source network, a user authentication start request message from the target authenticator in response to receiving the pre-authentication start request message transmitted by the mobile terminal; transmitting, by the mobile terminal and via the source network, a user authentication response message to the target authenticator in response to the user authentication start request message and generating an authentication key that is used for communication between the mobile terminal and the target authenticator; and transmitting, by the mobile terminal and via a target network, an attach request message for attaching the mobile terminal to the target network, the attach request message including the generated authentication key.