System and method for communication in a wireless mobile ad-hoc network

• US 20070038743A1
• Filed: 05/17/2006
• Published: 02/15/2007
• Est. Priority Date: 05/17/2005
• Status: Active Grant

• Current Assignee: Rajant Corporation
• Original Assignee: Rajant Corporation
• Inventors: Mansanpally, Rajashekhar, Hellhake, Paul, Hassick, Brian, Lamb, Martin, Parks, Joseph
• Granted Patent: US 8,341,289 B2
• Time in Patent Office: Days
• US Class Current: 709/224
• CPC Class Codes: H04L 45/36 Backward learning
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's
• CPC Class Codes: H04L 61/25 of the same type
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 61/5061 Pools of addresses
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 40/26 for hybrid routing by combining proactive and reactive routing
• CPC Class Codes: H04W 40/38 adapting due to varying relative distances between nodes
• CPC Class Codes: H04W 72/00 Local resource management
• CPC Class Codes: H04W 76/20 Manipulation of established connections
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user

Abstract

A system and method for improving digital communication in a wireless mobile ad-hoc network. More specifically, the system includes one or more portable network devices operable to support the seamless operation of a self-initializing, self-healing, adaptive portable network. The portable network devices implement protocols that provide bandwidth management capabilities for use with radios, routers and other wireless network devices. Each portable network device includes at least one wireless transceiver, a processor and control software. The processor and control software are logically coupled to the wireless transceiver to facilitate digital communication via a plurality of communication channels with other network devices.

Claims

1. A method of communication in an ad-hoc network, comprising:

providing at least one portable network device including a transceiver and a processor that implements a data communication protocol to communicate data to other network devices through one or more network ports connected to other devices in the network;

detecting an incoming data packet received by the portable network device and identifying a reception port on which the data packet was received;

reading header information associated with the data packet if header information is present, wherein the header information includes packet source and cost information;

comparing the header information and reception port with information in a bridge table in the portable network device to determine retransmission parameters for the data packet;

determining based on the retransmission parameters whether the data packet should be dropped or retransmitted through one or more of the network ports of the portable network device, and processing the data packet accordingly;

based on the results of said comparing step, determining whether a lower cost routing is available for packets to the source and if so, storing new cost and routing information for the source in the bridge table.

2. The method of claim 1, comprising the further step of determining whether the bridge table has an entry corresponding to the packet source and if not, creating a bridge table entry using the cost information provided in the packet.

3. The method of claim 1, comprising the further step of determining whether the bridge table has an entry corresponding to the packet destination, and if not, creating a bridge table entry for the packet destination.

4. The method of claim 1, comprising the further step of determining whether the incoming packet has been encoded with the header providing packet source and cost information, and if not, encoding the packet with such header before retransmitting the packet to a wireless device on the network.

5. The method of claim 1, wherein the data packet includes a protocol identifier indicating that the data packet includes a header to facilitate transmission in the mesh network.

6. The method of claim 5, comprising the further steps of changing the protocol identifier, removing header information from the received packet, and retransmitting it via a non-wireless port connection.

7. The method of claim 5, wherein reading the data packet header includes at least reading a destination address, source address, source sequence number (SSN), mesh protocol identifier, cost, and one or more mesh protocol flags.

8. The method of claim 7, wherein the mesh protocol flags comprise lower-order bits including an introductory flag, a discovery flag and an undeliverable flag.

9. The method of claim 1, wherein comparing header information with the bridge table includes comparing source information in the header with source information in the bridge table.

10. The method of claim 1, wherein comparing header information with the bridge table includes comparing destination information in the header with destination information in the bridge table.

11. The method of claim 1, wherein comparing header information with the bridge table includes comparing a timestamp associated with the data packet with a current timestamp.

31. The device of claim 1, wherein the protocol implements a distinctive ethertype identifier indicating that the data packet includes data to facilitate transmission in the mesh network.

12. A portable network device, comprising:

at least one wireless transceiver providing at least one network port;

a processor with a stored program implementing a wireless mesh data communication protocol to communicate received data to other network devices through one or more network ports connected to other devices in the network; and

a position-identifying device connected to the processor;

wherein the stored program of the processor selectively transmits position information received from the position-identifying device via said wireless transceiver in response to a received wireless administrative signal.

13. The device of claim 12, wherein the position-identifying device comprises at least one of a satellite receiver and an inertial guidance module.

14. The device of claim 12, wherein the portable network device further comprises a locator beacon.

15. The device of claim 12, wherein the locator beacon generates at least one of an audible signal and a visual signal.

16. The device of claim 12, wherein the processor activates the locator beacon in response to a wireless signal.

17. A portable network device, comprising:

at least one wireless transceiver providing at least one network port;

a processor with a stored program implementing a wireless mesh data communication protocol to communicate received data to other network devices through one or more network ports connected to other devices in the network; and

a visual indicator having at least three visually distinct operating states,

wherein the stored program of the processor determines whether the wireless transceiver is (a) not connected to another portable network device;

(b) connected to at least one portable network device;

or (c) connected to at least one portable network device with a signal strength exceeding a predetermined threshold defining a strong signal, and actuates the visual indicator in a visually distinct operating state for each of states (a), (b) and (c).

18. The device of claim 17, wherein the visual indicator is a tricolored LED.

19. The device of claim 17, further including a multiposition operating state selection switch connected to selectively place the portable network device into at least operating and data loading states.

20. The device of claim 19, further comprising an action switch connected to initiate a specified action depending on the position of the multiposition operating state selection switch.

21. The device of claim 20 further comprising a multiposition configuration switch connected to load one or more predetermined device operating parameters when the operating state selection switch is in a data loading position and the action switch is actuated.

22. A method of securely loading information into a portable network device operating in a wireless ad-hoc network, comprising:

a. providing a non-volatile storage in the portable network device to store an operating system, and routing protocols and related configuration settings that control operation of the device in the wireless network;

b. providing an interlock circuit in the portable network device that prevents simultaneously writing to the non-volatile storage and conducting wireless communications;

c. activating the interlock circuit to prevent wireless communications and permit writing to the non-volatile storage;

d. connecting an external data storage medium to the portable network device;

e. retrieving a file from the external data storage medium;

f. validating the file;

g. writing the file to the non-volatile storage; and

h. deactivating the interlock circuit to prevent further writing to the non-volatile storage and permit wireless communications.

23. The method of claim 22, wherein the interlock circuit comprises a multiposition switch having a RUN position and a LOAD position.

24. The method of claim 22, wherein the step of validating the file includes using public key encryption to verify that the file was generated by an authorized source.

25. The method of claim 22, comprising the further steps of:

i. Operating the device such that ad-hoc wireless devices that are not authenticated by an administrator are excluded from communications with the portable network device; and

j. Loading an authentication code provided by the administrator into the device using steps (b) through (h).

26. The method of claim 25, wherein the authentication code comprises a public key encryption certificate.

27. A mesh network device, comprising:

at least one wireless transceiver;

a processor that performs stored program steps to operate the mesh network device as a node in a network, implementing a data communication protocol that communicates data in a mesh network to other mesh network devices through one or more mesh network ports, such that the protocol provides packet source and cost information in conjunction with transmitted data packets;

a bridge table identifying known mesh network devices and cost information for data transmissions to the known mesh network devices; and

bridge table updating means for comparing the source and cost information associated with the data packet with bridge table information to determine whether a lower cost routing is available for packets to the source and if so, storing new cost and routing information for the source in the bridge table.

28. The device of claim 27, further comprising means for determining whether the bridge table has an entry corresponding to the packet source and if not, creating a bridge table entry using the cost information provided in the packet.

29. The device of claim 27, further comprising means for determining whether the bridge table has an entry corresponding to the packet destination, and if not, creating a bridge table entry for the packet destination.

30. The device of claim 27, further comprising means for determining whether the incoming packet has been encoded with a header providing packet source and cost information, and if not, encoding the packet with such header before retransmitting the packet to a wireless device on the network.

32. The device of claim 30, further comprising means for changing the protocol identifier, removing header information from the received packet, and retransmitting it via a non-wireless port connection.

33. The device of claim 30, wherein reading the data packet header includes at least reading a destination address, source address, source sequence number (SSN), mesh protocol identifier, cost, and one or more mesh protocol flags.

34. The device of claim 33, wherein the mesh protocol flags comprise lower-order bits including an introductory flag, a discovery flag and an undeliverable flag.