Method and system of updating routing/establishing paths in a hierarchical network

• US 7,978,633 B2
• Filed: 06/10/2004
• Issued: 07/12/2011
• Est. Priority Date: 06/11/2003
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Mizukoshi, Yasuhiro
• Primary Examiner(s): Wong; Warner
• Application Number:
  US10/864,413
• Publication Number:
  US 20040252708A1
• Time in Patent Office: 2,588 Days
• Field of Search: 370/328, 370/351, 370/400, 370/407, 455/445
• US Class Current: 370/256
• 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 system and method of establishing and routing paths in a network hierarchy is disclosed. A radio base station updates a path 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 radio base stations;

a plurality of intermediate-layer routers;

a plurality of highest-layer routers;

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

wherein each of said intermediate-layer routers selects one of said plurality of highest-layer routers as an upward router, according to a network address of each of the mobile terminals, and routes to the selected upward router,

wherein each of said intermediate-layer routers is connected to each of said highest-layer routers, without said intermediate layer routers being connected to each other.

2. The system of updating routing paths in a hierarchical network according to claim 1, 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.

3. The system of updating routing paths in a hierarchical network according to claim 2, 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 the upward router.

4. The system of updating routing paths in a hierarchical network according to claim 3, 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.

5. 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.

16. 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.

18. 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 of the plurality of mobile terminals corresponding to the logical network.

6. A method for establishing a path in a network in which a plurality of mobile terminals, a plurality of radio base stations, a plurality of intermediate-layer routers, and a plurality of highest-layer routers are hierarchically connected to one another, said method comprising:

a step of having each of said intermediate-layer routers select one of said plurality of highest-layer routers as an upward router, according to a network address of each of said mobile terminals, and route to the selected upward router,

wherein each of said intermediate-layer routers is connected to each of said highest-layer routers, without said intermediate-layer routers being connected to each other.

7. The method for establishing a path according to claim 6, wherein each of a plurality of lowest-layer routers 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.

8. The method for establishing a path according to claim 7, wherein each of said lowest-layer routers and each of said intermediate-layer routers establish a path to each of said mobile terminals and notify path information to said upward router.

9. The method for establishing a path according to claim 8, wherein, when a radio link between each of said mobile terminals and each of said radio base stations is set up, a path to each of said mobile terminals is established in response to a path updating notification made by each of said mobile terminals.

10. The method for establishing a path according to claim 6, wherein at least one default router is arranged among said plurality of highest-layer routers.

17. The method for establishing a path according to claim 6, 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.

19. The method for establishing a path according to claim 6, 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.

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

a plurality of mobile terminals;

a plurality of radio base stations;

a plurality of intermediate-layer routers;

a plurality of highest-layer routers;

wherein said mobile terminals, said radio base stations, 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 means to select one of said plurality of highest-layer routers as an upward router, according to a network address of each of said mobile terminals, and route to the selected upward router,

wherein each of said intermediate-layer routers is connected to each of said highest-layer routers, without said intermediate-layer routers being connected to each other.

12. The system of updating routing paths in a hierarchical network according to claim 11, 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.

13. The system of updating routing paths in a hierarchical network according to claim 12, 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 the upward router.

14. The system of updating routing paths in a hierarchical network according to claim 13, 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.

15. The system of updating routing paths in a hierarchical network according to claim 11, wherein at least one default router is defined among said plurality of highest-layer routers.