METHOD AND SYSTEM OF UPDATING ROUTING/ESTABLISHING PATHS IN A HIERARCHICAL NETWORK

• US 20110228741A1
• Filed: 06/03/2011
• Published: 09/22/2011
• Est. Priority Date: 06/11/2003
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: MIZUKOSHI, Yasuhiro
• Granted Patent: US 8,780,764 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing

Abstract

A mobile unit managing network is provided which is capable of supporting a communication area being wider than ever by one highest-layer router. A radio base station transfers a path updating notification fed from a mobile terminal to a lowest-layer router. The lowest-layer router establishes a path in which a network address to the mobile terminal exists in the radio base station and transfers path information to an intermediate-layer router serving as an upward router. The intermediate-layer router establishes a path in which the network address to the mobile terminal exists in the lowest-layer router and transfers path information to the highest-layer router. The highest-layer router, when having received path information notification from the intermediate-layer router, establishes a path in which the network address to the mobile terminal exists in the intermediate-layer router.

Claims

1. A system of updating routing paths in a hierarchical network comprising:

a plurality of mobile terminals;

a plurality of intermediate-layer routers;

a plurality of highest-layer routers;

wherein said mobile terminals, said intermediate-layer routers and said highest-layer routers are hierarchically connected to one another; and

wherein each of said intermediate-layer routers manages each of network addresses which are assigned respectively to said mobile terminals.

2. The system of updating routing paths in a hierarchical network according to claim 1, further comprising a plurality of radio base stations, each of which is connected to each of said intermediate-layer routers, wherein each of said mobile terminals sets up a radio link with each of said radio base stations.

3. The system of updating routing paths in a hierarchical network according to claim 2, further comprising a plurality of lowest-layer routers, each of which is connected between a plurality of said radio base stations and the corresponding intermediate-layer router, wherein each of said lowest-layer routers and each of said intermediate-layer routers perform a path establishing process to disperse a load of each of said highest-layer routers.

4. The system of updating routing paths in a hierarchical network according to claim 3, wherein each of said lowest-layer routers and each of said intermediate-layer routers establishes a path to each of said mobile terminals and notifies path information to an upward router.

5. The system of updating routing paths in a hierarchical network according to claim 4, wherein said establishing the path to each of said mobile terminals, when a radio link between each of said mobile terminals and each of said radio base stations is set up, establishes a path to each of said mobile terminals in response to a path updating notification made by each of said mobile terminals.

6. The system of updating routing paths in a hierarchical network according to claim 1, wherein at least one default router is defined among said plurality of highest-layer routers.

19. The system of updating routing paths in a hierarchical network according to claim 1, wherein each of said intermediate-layer routers routes to an upward router based on correspondence between address of the mobile terminal and the network prefix assigned to a highest layer router of the plurality of highest-layer routers.

21. The system of updating routing paths in a hierarchical network according to claim 1, wherein each highest-layer router of the plurality of highest-layer routers manages a logical network, the network address of each mobile terminal corresponding to the logical network.

7. A method for updating routing paths in a network including a plurality of mobile terminals, a plurality of intermediate-layer routers, and a plurality of highest-layer routers, the method comprising:

a step of connecting hierarchically to one another said mobile terminals, said intermediate-layer routers, and said highest-layer routers and

a step of having each of said intermediate-layer routers manage each of network addresses which are assigned respectively to said mobile terminals.

8. The method for updating routing paths in a network according to claim 7, wherein said network further comprises a plurality of radio base stations, each of which is connected to each of said intermediate-layer routers, wherein each of said mobile terminals sets up a radio link with each of said radio base stations.

9. The method for updating routing paths in a network according to claim 8, wherein said network further comprises a plurality of lowest-layer routers, each of which is connected between a plurality of said radio base stations and the corresponding intermediate-layer router, wherein each of said lowest-layer routers and each of said intermediate-layer routers perform a path establishing process to disperse a load of each of said highest-layer routers.

10. The method for updating routing paths in a network according to claim 9, wherein each of said lowest-layer routers and each of said intermediate-layer routers establishes a path to each of said mobile terminals and notifies path information to an upward router.

11. The method for updating routing paths in a network according to claim 10, wherein said establishing the path to each of said mobile terminals, when a radio link between each of said mobile terminals and each of said radio base stations is set up, establishes a path to each of said mobile terminals in response to a path updating notification made by each of said mobile terminals.

12. The method for updating routing paths in a network according to claim 7, wherein at least one default router is defined among said plurality of highest-layer routers.

20. The method for updating routing paths in a network according to claim 7, wherein each of said intermediate-layer routers routes to an upward router based on correspondence between address of the mobile terminal and the network prefix assigned to a highest layer router of the plurality of highest-layer routers.

22. The method for updating routing paths in a network according to claim 7, wherein each highest-layer router of the highest-layer routers manages a logical network, the network address of each mobile terminal corresponding to the logical network.

13. A system of updating routing paths in a hierarchical network comprising:

a plurality of mobile terminals;

a plurality of intermediate-layer routers;

a plurality of highest-layer routers;

wherein said mobile terminals, said intermediate-layer routers and said highest-layer routers are hierarchically connected to one another; and

wherein each of said intermediate-layer routers comprises a unit to manage each of network addresses which are assigned respectively to said mobile terminals.

14. The system of updating routing paths in a hierarchical network according to claim 13, further comprising a plurality of radio base stations, each of which is connected to each of said intermediate-layer routers, wherein each of said mobile terminals sets up a radio link with each of said radio base stations.

15. The system of updating routing paths in a hierarchical network according to claim 14, further comprising a plurality of lowest-layer routers, each of which is connected between a plurality of said radio base stations and the corresponding intermediate-layer router, wherein each of said lowest-layer routers and each of said intermediate-layer routers perform a path establishing process to disperse a load of each of said highest-layer routers.

16. The system of updating routing paths in a hierarchical network according to claim 15, wherein each of said lowest-layer routers and each of said intermediate-layer routers comprise a means to establish a path to each of said mobile terminals and to notify path information to an upward router.

17. The system of updating routing paths in a hierarchical network according to claim 16, wherein said means to establish the path to each of said mobile terminals, when a radio link between each of said mobile terminals and each of said radio base stations is set up, establishes a path to each of said mobile terminals in response to a path updating notification made by each of said mobile terminals.

18. The system of updating routing paths in a hierarchical network according to claim 13, wherein at least one default router is defined among said plurality of highest-layer routers.