Mobile terminal management system, mobile terminal, agent, and program

A mobile terminal management system comprising:

• a network that includes a plurality of subnetworks interconnected with each other;
• and
• a plurality of mobile terminals, each having a Care-Of (C/O) address depending on a subnetwork to which the mobile terminal is currently connected and a home address which is independent of the subnetwork, wherein:
• in response to the subnetwork connected to a mobile terminal changing, a plurality of communication parties are notified of a pair of the latest C/O address and home address of the mobile terminal;
• the mobile terminal management system, further comprising a means for deciding whether a foreign agent function of each of the plurality of mobile terminals is placed in a first radio base station or in a first node when registering the location of the mobile terminal.

A mobile terminal having a Care-Of (C/O) address depending on a subnetwork to which the mobile terminal is currently connected and a home address which is independent of the subnetwork, comprising:

• means for storing and managing a communication party list;
• and
• means for transmitting a binding update request to report a new C/O address with the communication party list attached to the binding update request, in response to a change in the subnetwork to which the mobile terminal is connected;
• wherein the subnetwork to which the mobile terminal is connected is comprised by a network comprising a means for deciding whether a foreign agent function of each of a plurality of mobile terminals is placed in a first radio base station or in a first node when registering the location of the mobile terminal.

An agent in a network that includes a plurality of subnetworks interconnected with each other and that includes mobile terminals each having a Care-Of (C/O) address depending on a subnetwork to which the mobile terminal is currently being connected and a home address that is independent of the subnetwork, comprising:

• means for receiving a binding update request sent from each mobile terminal when the subnetwork connected to the mobile terminal has changed;
• and
• means for notifying respective communication parties in a communication party list attached to the received binding update request about a pair of the latest C/O address and home address of the mobile terminal;
• wherein the network comprises a means for deciding whether a foreign agent function of each of a plurality of mobile terminals is placed in a first radio base station or in a first node when registering the location of the mobile terminal.

A computer-readable storage medium storing instructions for enabling a computer constituting a mobile terminal having a Care-Of (C/O) address depending on a subnetwork to which the mobile terminal is currently connected and a home address which is independent of the subnetwork, to function as:

• means for storing and managing a communication party list;
• and
• means for transmitting a binding update request to report a new C/O address with the communication party list in response to a change in the subnetwork to which the mobile terminal is connected;
• wherein the subnetwork to which the mobile terminal is connected is comprised by a network comprising a means for deciding whether a foreign agent function of each of a plurality of mobile terminals is placed in a first radio base station or in a first node when registering the location of the mobile terminal.

A computer-readable storage medium storing instructions for enabling a computer constituting an agent in a network that includes a plurality of subnetworks interconnected with each other and that includes mobile terminals each having a Care-Of (C/O) address depending on a subnetwork to which the mobile terminal is currently connected and a home address which is independent of the subnetwork, to function as a

• means for receiving a binding update request sent from each mobile terminal when the subnetwork connected to the mobile terminal has changed;
• and
• means for notifying respective communication parties in a communication party list attached to the received binding update request about a pair of the latest C/O address and home address of the mobile terminal;
• wherein the network comprises a means for deciding whether a foreign agent function of each of a plurality of mobile terminals is placed in a first radio base station or in a first node when registering the location of the mobile terminal.