Method and system for routing packets in a packet communication network

• US 5,115,433 A
• Filed: 04/20/1990
• Issued: 05/19/1992
• Est. Priority Date: 07/18/1989
• Status: Expired due to Term

• Current Assignee: Proxim Wireless Corporation
• Original Assignee: Metricom, Inc.
• Inventors: Kalkwarf, Robert L., Baran, Paul, Flammer, George H. III
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): HSU, ALPUS
• Application Number:
  US07/513,364
• Time in Patent Office: 760 Days
• Field of Search: 370/94.1, 370/94.2, 370/94.3, 370/60, 370/60.1, 370/85.7, 340/825.5, 340/825.51, 340/825.52
• US Class Current: 370/400
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing

Abstract

A packet network routing method and system based on geographic coordinate identifiers is described. Each node in a network is uniquely identified by absolute geographical coordinates or by a code indicating absolute location in an external coordinate-based reference system (node coordinates), and such absolute geographical coordinates or the equivalent are employed as part of a packet identifier for each packet generated for use in making routing decisions. The node coordinates of a local node and its neighboring nodes and the packet coordinates are used by means at each node through which a packet is routed for determining a desired forwarding route of a data packet. The routing may be prioritized according to preselected criteria, preferably achieving maximum forward progress using the least amount of power. The packet routing protocol according to the invention requires no routing directory or table to perform data routing.

Claims

1. A method for routing packets of data without a network director comprising the steps of:

assigning to each node in a network an identifier indicative of geographic location, said identifier including a coordinate value referenced to a terrestrial grid;

addressing a packet to an ultimate destination node by designating in a packet header said ultimate destination node only by said coordinate value of said ultimate destination node and without designating a complete intermediate path to said ultimate destination node such that the network is free to route the packet via any intermediate path to said ultimate destination node;

at a lock node, selecting at least one of a plurality of neighboring nodes by using said packet header and other information specific to said lock node according to preselected criteria;

forwarding said packet to said selected neighboring node for eventual delivery to said ultimate destination node; and

selecting one neighboring node requiring the least amount of power for forwarding said packet.

2. The method according to claim 1 wherein said selecting step includes using said packet header to determine distance of said plurality of neighboring nodes relative to said ultimate destination node.

3. The method according to claim 1 wherein said selecting step includes developing a local table for maintaining communication history between said lock node and said plurality of neighboring nodes.

4. The method according to claim 3 wherein said lock table maintains information about said neighboring nodes on at least one of the following criteria:

distance, output power required to establish communication, retry history, throughput history, speed of transfer, network delay, data priority, link utilization percentage, closeness to desired destination closeness to desired bearing, randomness, and closeness to local bearing.

5. The method according to claim 3 wherein a link quality factor is employed to define preferred communication paths.

6. A system for routing packets of data in a packet data communication network without a network director comprising:

a plurality of nodes in a network, each node including an identifier indicative of geographic location, said identifier including a coordinate value referenced to a terrestrial grid; and

means for addressing a packet to an ultimate destination node by designating in a packet header said ultimate destination node only by said coordinate value of said ultimate destination node and without designating a complete intermediate path to said ultimate destination node such that the network is free to route the packet via any intermediate path to said ultimate destination node.

7. A system for routing packets of data without a network director comprising:

a plurality of nodes in a network, each node including an identifier indicative of geographic location, said identifier including a coordinate value referenced to a terrestrial grid;

means for addressing a packet to an ultimate destination node by designating in a packet header said ultimate destination node only by said coordinate value of said ultimate destination node and without designating a complete intermediate path to said ultimate destination node such that the network is free to route the packet via any intermediate path to said ultimate destination node;

at a lock node, means for selecting at least one of a plurality of neighboring nodes by using said packet header and other information specific to said lock node according to preselected criteria; and

means for forwarding said packet to said selected neighboring node for eventual delivery to said ultimate destination node.

8. The system according to claim 7 wherein said selecting means comprises means for selecting one neighboring node requiring the least amount of power for forwarding said packet.

9. The system according to claim 7 wherein said selecting means includes means for using said packet header to determine distance of said plurality of neighboring nodes relative to said ultimate destination node.

10. The system according to claim 7 wherein said selecting means includes means for developing a local table for maintaining communication history between said local node and said neighboring nodes.

11. The system according to claim 10 wherein said local table maintains information about said neighboring nodes on at least one of the following criteria:

distance, output power required to establish communication, retry history, throughput history, speed of transfer, network delay, data priority, link utilization percentage, closeness to desired destination, closeness to desired bearing, randomness, and closeness to local bearing.

12. The system according to claim 10 wherein a link quality factor is employed to define preferred communication paths.