Route discovery based piconet forming

• US 6,751,200 B1
• Filed: 10/26/2000
• Issued: 06/15/2004
• Est. Priority Date: 12/06/1999
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Larsson, Tony, Johansson, Per, Sörensen, Johan
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US09/696,242
• Time in Patent Office: 1,328 Days
• Field of Search: 370/254-258, 370/335, 370/449, 706/21
• US Class Current: 370/255
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/26 Route discovery packet
• CPC Class Codes: H04W 40/246 Connectivity information discovery
• CPC Class Codes: H04W 40/28 for reactive routing
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A method for establishing a route over which data packets are to be sent from a source node to a destination node in an ad-hoc network is provided. A source having packets to send to a destination node employs a reactive routing protocol if it does not posses the route to the destination node. Initially, it may be determined whether or not the source node is a member of an existing piconet. If the source node is a member of an existing piconet, a ROUTE request message may be broadcast to the nodes of the existing piconet, while the source awaits a timely REPLY message. If the source node is not a member of an existing piconet, or if a time REPLY message is not received, the source node may initiate a new route discovery process wherein the nodes attempt to establish new piconets that enable more efficient communication between the source and destination nodes.

Claims

1. In a telecommunications network, a method for establishing a route over which data packets are to be sent from a source node to a destination node comprising the steps of:

requesting route discovery between the source node and the destination node over existing network connections;

determining whether said request for route discovery between the source node and the destination node over existing network connections fails; and

establishing a route between the source node and the destination node by forming one or more new network connections if it is determined that said request for route discovery between the source node and the destination node over existing network connections failed.

2. The method of claim 1, wherein said step of determining whether said request for route discovery between the source node and the destination node over existing network connections fails comprises the step of:

determining whether the source node received a timely reply in response to the request for route discovery.

3. The method of claim 2, wherein said telecommunications network is an ad-hoc network.

4. The method of claim 3, wherein said network is a Bluetooth technology based network.

5. In an ad-hoc, radio telecommunications network that includes one or more existing subnetworks, a method for establishing a route between a source node and a destination node over which data packets are to be sent, said method comprising the steps of:

broadcasting a route discovery request message, for a route between the source node and the destination node over one or more connections associated with the one or more existing subnetworks, if the source node is a member of one or more of the existing subnetworks;

determining if a timely reply message is received by the source node in response to the broadcasting of the route discovery request message; and

establishing a route between the source node and the destination node over one or more new connections associated with one or more newly formed subnetworks, if it is determined that a timely reply message was not received.

6. The method of claim 5 further comprising the step of:

establishing a route between the source node and the destination node over one or more new connections associated with one or more newly formed subnetworks, if the source node is not a member of one or more of the existing subnetworks.

7. The method of claim 5 further comprising the step of:

establishing a route between the source node and the destination node over one or more new connections associated with one or more newly formed subnetworks, if the destination node is not a member of one or more of the existing subnetworks.

8. The method of claim 5 further comprising the step of:

determining whether a route over one or more new connections associated with one or more newly formed subnetworks is desirable, if it is determined that a timely reply in response to the route discovery request message is received by the source node.

9. The method of claim 8 further comprising the step of:

establishing a route between the source node and the destination node over one or more connections associated with the one or more existing subnetworks, if it is determined that a timely reply in response to the route discovery request message is received and it is determined that a route over one or more new connections associated with one or more newly formed subnetworks is not desirable.

10. The method of claim 8 further comprising the steps of:

establishing a route between the source node and the destination node over one or more connections associated with the one or more existing subnetworks, if it is determined that a timely reply in response to the route discovery request message is received and it is determined that a route over one or more new connections associated with one or more newly formed subnetworks is desirable; and

simultaneously, initiating route discovery for a route between the source node and the destination node over one or more connections associated with one or more newly formed subnetworks.

11. The method of claim 5, wherein said ad-hoc, radio telecommunications network is a Bluetooth technology based network.

12. The method of claim 11, wherein the existing and newly formed subnetworks are piconets.