Method and apparatus for mobile network

• US 20060018299A1
• Filed: 12/15/2004
• Published: 01/26/2006
• Est. Priority Date: 07/07/2004
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamamoto, Junji
• Granted Patent: US 7,453,842 B2
• Time in Patent Office: Days
• US Class Current: 370/349
• CPC Class Codes: H04W 8/065 involving selection of the user mobility server
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

A method and a device to resolve the problem of long communication paths between a mobile node, and a node not supporting mobile IP wherein a plurality of home agents are established in the network and by using the anycast address as the home address, the home agent nearest the communication node or mobile node is selected from among the home addresses.

Claims

1. A network control method for a network system for communicating with mobile nodes and utilizing two addresses comprised of a care-of address and a home address in a mobile node, wherein

the method manages the matching of the care-of address with the mobile node home address, and utilizes a plurality of home agents in different networks for relaying packets from the mobile node and/or relaying packets to the mobile node.

2. A network control method for a network system according to claim 1, wherein the routing information is comprised of the home address as the anycast address of the mobile node.

3. A network control method for a network system according to claim 2, wherein the routing information is comprised of the prefix of the home address as the anycast address.

4. A network control method according to claim 1, utilizing a master server including a link table for linking the home agent and the mobile node for managing the matching of the care-of address with the home address of the mobile node.

8. A network control method according to claim 1, wherein the home agent managing the matching of the mobile node home address and the care-of address, contain a plurality of home agent tables.

5. A mobile network control method including a master server and a plurality of home agents, wherein the first home agent where the care-of address of the mobile node is registered, includes a step for registering that first agent and the mobile node in the master server.

6. A mobile network control method according to claim 5, comprising:

a step for the second home agent to receive a packet addressed to the home address of the mobile node;

a step for the second home agent to search for the care-of address matching the mobile node;

a step for querying the master server about the first home agent managing the mobile node, when there is no care-of address;

a step for the second home agent to relay the packet to the first home agent; and

a step for the first home agent to relay the packet to the care-of address of the mobile node.

7. A mobile network control method according to claim 6, wherein the mobile node that received communication relayed from the second home agent, registers the care-of address in the second home agent.

9. A mobile network control method which includes a plurality of home agents, comprising:

a step for the second home agent to receive a packet addressed to the home address of the mobile node;

a step for the second home agent to search for the care-of address matching the mobile node when there is no care-of address;

a step for querying other home agents on whether there is a first home agent managing the mobile node;

a step for the second home agent to relay the packet to the first home agent; and

a step for the first home agent to relay the packet to the care-of address of the mobile node.

10. A network system connected by cable or radio with a first node, with the first node utilizing two addresses including a home address and a care-of address, with said network system comprising:

a plurality of home agents including a binding list for managing the matching of the home address and the care-of address; and

a master server for managing the matching between the first node, and the home agent containing a binding list used by the first node.

11. A network system according to claim 10 wherein the home address is an anycast address.

12. A network system according to claim 11, wherein during access of the first node by the second node connected to the network system, the second node issues a packet by an anycast address, and the issued packet is relayed to the first home agent that is one of the home agents by routing based on the anycast address, when the home agent does not contain a binding list used by the first node, the first agent queries the master server about home agents containing a binding list used by the first node.

13. A network system according to claim 12 wherein the issued packet is relayed to the first node from the first agent by way of the second home agent as a home agent containing a binding list used by the first node.

14. A network system according to claim 12, wherein after a flag is attached to the issued packet by the first home agent showing the route was via the first home agent, the issued packet is relayed to the first node via the second home agent as a home agent containing a binding list used by the first node.

15. A network system according to claim 14, wherein the first node that received the packet attached with a flag indicating the route is via the first home agent, registers the binding list used by the first node in the first home agent.

16. A server connected to a network system including a plurality of home agents containing binding lists for managing the matching of the care-of address with the home address, and utilizing two addresses comprised of a care-of address and a home address, wherein the server manages the matching of the node, and the home agents containing a binding list used by the node.

17. A server according to claim 16, comprising a mobile node—

home agent link table, wherein

each entry in the mobile node—

home agent link table is made up of information specifying the node, and a list of home agent groups where node care-of addresses are registered.

18. A server according to claim 17, comprising:

a packet processor;

an interrogator processor; and

a memory, wherein

the mobile node—

home agent link table is stored in the memory, the packet processor includes a function to shift the processing to the interrogator processor when a packet query is received about home agents where care-of addresses for a specific node are registered, and

the interrogator processor searches the list of home agents from the mobile node—

home agent link table where the care-of address of the specified node is registered, and the interrogator processor contains a function to return a packet containing the list information to the source making the query.

19. A home agent connected to a network system including a node, and a master server, and containing a binding list for managing the matching between the home address of the node, and the care-of address, wherein the home agent comprising:

a packet processor made up of an interface with an external section;

a master server interrogator section for querying the master server;

a mobile node—

master server link table for managing the combining of information specifying a node and information specifying a master server.

20. A home agent according to claim 19, comprising:

a mobile IP processor to search the binding list to find whether or not there is a care-of address matching the home address of the applicable node when a specified packet was sent from a specified node; and

a master server interrogator to search the master server for the specified node from the mobile node—

master server link table when results from searching the binding table show there is no care-of address, and query the searched master server for home agents registered with a care-of address for the specified node.