Method for multihop routing for distributed WLAN networks

• US 7,443,822 B2
• Filed: 09/11/2002
• Issued: 10/28/2008
• Est. Priority Date: 09/27/2001
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Larsson, Peter, Lindskog, Jan, Rydnell, Gunnar
• Primary Examiner(s): Pham; Chi H.
• Assistant Examiner(s): TRAN, PHUC H
• Application Number:
  US10/488,512
• Publication Number:
  US 20050013253A1
• Time in Patent Office: 2,239 Days
• Field of Search: 370/329, 370/330, 370/343, 370/344, 370/338
• US Class Current: 370/338
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/121 by minimising delays
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2408 for supporting different services, e.g. a differentiated services [DiffServ] type of service
• CPC Class Codes: H04L 47/283 in response to processing delays, e.g. caused by jitter or round trip time [RTT]
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 28/24 Negotiating SLA [Service Level Agreement]; Negotiating QoS [Quality of Service]
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 40/246 Connectivity information discovery
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method for multihop packet trasmissions in a wireless network involves establishing a multihop route through the wireless network. After establishment of the multihop route, transmission protocol parameter are altered to minimize delays for transmissions over the multihop route and at least one packet is transmitted over the multihop route according to the altered transmission protocol parameters. In a first embodiment, the altering of the transmission protocol parameters includes setting a NAV value at each node of the multihop route for a duration of the packet transmissions over the route. In an alternative embodiment, multihop packets are assigned a higher QoS value.

Claims

1. A method for transmitting multihop packet transmissions in a wireless network, said method comprising the steps of:

establishing a multihop route through a wireless network;

altering transmission protocol parameters to minimize delays for packet transmissions over the multihop route; and

,

transmitting at least one packet over the route according to the altered transmission protocol parameters;

wherein the step of altering comprises the step of setting a Network Allocation Vector (NAV) value at each node of the route for a duration of the packet transmissions over the route.

2. The method of claim 1, wherein the step of establishing comprises the steps of:

transmitting a route request message requesting the multihop route from a first node to a second node;

gathering route data related to the route as the first message travels from the first node to the second node; and

transmitting a route response message back to the first node from the second node.

3. The method of claim 2, wherein the step of altering further comprises the steps of:

calculating a duration value indicating an amount of time necessary to complete the multihop packet transmission responsive to the gathered route data;

including the duration value in the route response message; and

setting the NAV value at each node of the multihop route responsive to the duration value for a period of time indicated by the duration value.

4. The method of claim 3, further including the step of resetting the NAV value after completion of the transmission.

5. The method of claim 3, further including the step of resetting the NAV value if the transmission ends prior to a time indicated by the duration value.

6. The method of claim 3, wherein the step of establishing further includes the step of determining the multihop route from a previous route determination.

7. The method of claim 3, wherein the duration value is determined from a previous transmission and included in the route request message.

8. The method of claim 2, wherein said route request and route response messages are transmitted according to a high priority.

9. The method of claim 2, further including the steps of:

determining a second duration value, the second duration value equal to a determined transmission time from the first node to the second node; and

setting the NAV value responsive to the duration value until completion of the route response message.

10. The method of claim 1, wherein the NAV value is only set once a node begins to receive a packet transmission.

11. The method of claim 1, wherein the step of altering comprises the step of establishing a higher Quality-of-Service (QoS) class for a multihop packet.

12. The method of claim 11, further including the step of determining if a packet is a multihop packet.

13. The method of claim 12, wherein the step of determining comprises the step of analyzing address fields of a MAC header of the packet to determine if a source and destination address are in a same Independent Basis Service Set (IBSS).

14. The method of claim 12, wherein the step of determining comprises the step of identifying a data field in the MAC header of the packet indicating a multihop packet.