Method and structure for autoconfiguration of network destinations

• US 20030235155A1
• Filed: 06/21/2002
• Published: 12/25/2003
• Est. Priority Date: 06/21/2002
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Boivie, Richard H., Feldman, Nancy K.
• Granted Patent: US 7,580,370 B2
• Time in Patent Office: Days
• US Class Current: 370/238
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/26 Route discovery packet
• CPC Class Codes: H04L 45/46 Cluster building
• CPC Class Codes: H04L 45/64 using an overlay routing layer

Abstract

A method (and structure) for determining an optimal routing of data packets to subnet addresses in a network including a plurality of routers interrelated by a defined neighborhood relationship, includes, responsive to learning of a presence of a subnet, determining a distance between the subnet and each router.

Claims

1. A method of determining an optimal subnet data-packet-routing in a network comprising a plurality of routers interrelated by a defined neighborhood relationship, said method comprising:

responsive to learning of a presence of a subnet, determining a distance between said subnet and each router in said plurality of routers.

2. The method of claim 1, further comprising:

determining, for each said router, an optimal routing procedure to use when said router receives a data packet addressed to said subnet, said optimal routing procedure defining whether each said router should forward said data packet directly to said subnet or to a neighboring router.

3. The method of claim 2, further comprising:

for each router having more than one neighboring router, determining a specific one of said neighboring routers to forward said data packets addressed to said subnet, if said optimal routing procedure for data packets to said subnet comprises forwarding said data packets to a neighboring router.

4. The method of claim 1, further comprising:

in a first router of said network, responsive to learning of a presence of said subnet, communicating with said subnet to allow said first router to measure a distance D₀ between said first router and said subnet; and

transmitting distance D₀ to each router R₁ (where i is an integer equal to or greater than one) defined as being a neighbor of said first router.

5. The method of claim 4, further comprising:

in each neighbor router R₁, communicating with said subnet to allow each router R₁ to measure a respective distance D₁ to said subnet.

6. The method of claim 5, wherein an optimal routing procedure for said first router comprises:

sending said data packets from said first router directly to said subnet, if said distance D₀ is smallest of all said distances D₁; and

sending said data packets from said first router to whichever neighboring router R₁ has the smallest distance D₁, if said distance D₀ is not smallest of all said distances D₁.

7. The method of claim 6, further comprising:

designating said first router to be a local router for said subnet if said distance D₀ is smallest of all said distances D₁.

8. The method of claim 6, wherein each said neighboring router R₁ transmits its said respective distance D₁ to said first router and a determination of an optimal routing for said first router to said subnet occurs in said first router.

9. The method of claim 4, wherein said distance D₀ is determined by pinging to said subnet to determine a time interval.

10. The method of claim 4, further comprising:

periodically repeating said communicating to determine whether said optimal routing should be revised.

11. The method of claim 1, wherein each said router, responsive to learning of said subnet in any manner, determines a distance between itself and said subnet.

12. A computer for determining an optimal routing of data packets to subnets contained in a network, said network comprising a plurality of routers organized by a relationship defining how said plurality of routers are related as neighboring routers, said computer comprising:

an awareness module for learning of a presence of a subnet on said network;

a receiver to receive data packets addressed to said subnet and transmissions from any neighboring router;

a transmitter for communicating with said subnet and with any neighboring router; and

a timing detector for determining from said communication a time interval corresponding to a distance to said subnet.

13. The computer of claim 12, further comprising:

a calculator for using said time interval to determine an optimal routing procedure to use whenever receiving a data packet addressed to said subnet, said optimal routing procedure defining whether to transmit said data packet directly to said subnet or to transmit said data packet to a neighboring router, an optimal routing determined by comparing said distance to said subnet with a distance to said subnet as reported by each neighboring router.

14. The computer of claim 12, further comprising:

a timer such that said communication with said subnet is periodically repeated to determine a current distance to said subnet.

15. A network comprising:

a plurality of routers; and

a calculator to determine an optimal routing for data packets addressed to a subnet, wherein said optimal routing is determined based on determining which router is currently closest to said subnet.

16. The network of claim 15, wherein an optimal routing procedure is determined for each said router, said optimal routing procedure to be used to forward any data packets received by said router and addressed to said subnet.

17. The network of claim 16, wherein said optimal routing and said optimal routing procedure are periodically updated based on current network conditions.

18. The network of claim 16, wherein said optimal routing procedure for each router is determined by each said router.

19. A signal-bearing medium tangibly embodying a program of machine-readable instructions executable by a digital processing apparatus to perform a method of determining an optimal routing of data packets to subnets, said network comprising a plurality of routers organized by a relationship defining how said plurality of routers are interrelated as neighboring routers, said method comprising:

responsive to learning of a presence of a subnet, determining a distance between said subnet and each router.

20. The signal-bearing medium of claim 19, said method further comprising:

upon said learning of a presence of a subnet on said network, determining for each router, an optimal routing procedure to use upon receiving a data packet addressed to said subnet, said optimal routing procedure defining whether said router should forward said data packet directly to said subnet or to a neighboring router.