Abstract: A method for reconfiguring the security mechanism of a wireless network system includes steps of: sending a packet from a network node to a mobile node; sending a negotiation packet from the mobile node to the network node according to a selected authentication protocol; the mobile node and the network node proceeding the authentication process if the received negotiation packet is valid; the mobile node and the network node generating a security association after the authentication process is completed.

Abstract: A home agent (200) for registering with a serving node (400) in a home network (10) includes a packet filter module (210), an agent control module (220), and a registration module (240). The packet filter module detects a mobile registration packet transmitted from a mobile node (100) and informs the agent control module. The registration module registers with the serving node by transmitting a registration request packet when the agent control module is informed by the packet filter module. The registration request packet includes a home address field and a care-of address (CoA) field. The home address field is set to an Internet protocol (IP) address of the mobile node in the home network, and the CoA field is set to an IP address of the home agent. A registration method, a network system, and a network roaming method are also provided.

Abstract: A mobile node (10) roams from a home network to a foreign network, and comprises an address detection module (101) and an address conversion request module (107). The address detection module detects a current address of the mobile node. The address conversion request module transmits an address conversion request message to a home agent according to the current address of the mobile node and an address of the home agent, receives an address conversion response message from the home agent, and generates an address mapping relationship between a home address and the current address of the mobile node. A network system and a network roaming method are also provided.

Abstract: A method for reconfiguring a mobility platform includes: enabling a mobile node to extract an advertisement signaling packet sent periodically by a network node, wherein the mobile node supports a plurality of client mobility management protocols, and the network node supports a plurality of network mobility management protocols; according to the advertisement signaling packet, enabling the mobile node to display at least one mobility management protocol that is mutually supported by the mobile and network nodes for viewing by a user; enabling the user to select one of the at least one mobility management protocol to serve as a new mobility management protocol to be mutually used by the mobile and network nodes; and enabling the mobile node to send a registration request packet to the network node.