Content throughput on wireless mesh networks

• US 20080043638A1
• Filed: 08/17/2006
• Published: 02/21/2008
• Est. Priority Date: 08/17/2006
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Ribiere, Vincent, Thubert, Pascal, Wetterwald, Patrick
• Granted Patent: US 8,391,255 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/2441 relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/28 in relation to timing considerations
• CPC Class Codes: H04W 28/02 Traffic management, e.g. flow control or congestion control
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 72/569 of the traffic information
• CPC Class Codes: H04W 74/0875 with assigned priorities based access
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

In one embodiment, a method includes receiving an inbound data packet over a wireless link at a wireless intermediate network node. The inbound data packet indicates the packet was transmitted by a node at an edge of the mesh. The inbound data packet is associated with a low priority minimum wait interval and a low priority maximum wait interval for reducing contention on the wireless link. An outbound data packet based on the first data packet is transmitted over the wireless link after a wait time. The wait time is based on a high priority minimum wait interval and a high priority maximum wait interval for reducing contention. The low priority minimum wait interval is greater than the high priority minimum wait interval. These techniques allow long packet queues at the edge but quickly clear packets already forwarded by the mesh.

Claims

1. A method comprising the steps of:

receiving, over a wireless link at a wireless intermediate network node of a wireless mesh network, a first data packet that includes data that indicates that the first data packet was transmitted by a sending node that is one of a wireless end node and a wireless roof top access point connected by a wire to a wired subnetwork, wherein the first data packet is associated with first configured values for a first minimum wait interval and a first maximum wait interval for reducing contention for the wireless link; and

transmitting over the wireless link a second data packet based on the first data packet after a wait based on second configured values for a different second minimum wait interval and a different second maximum wait interval for reducing contention for the wireless link,

wherein the first minimum wait interval is greater than the second minimum wait interval.

2. A method as recited in claim 1, wherein the first minimum wait interval is greater than the second maximum wait interval.

3. A method as recited in claim 1, wherein:

the method further comprises determining a maximum hop time for a data packet to hop to an adjacent intermediate network node in the wireless mesh network; and

the second minimum wait interval is not less than the maximum hop time.

4. A method as recited in claim 3, wherein the second minimum wait interval is substantively equal to the maximum hop time.

5. A method as recited in claim 1, wherein:

the first data packet is formatted as a frame of Institute of Electrical and Electronics Engineers (IEEE) standard 802.11;

the IEEE 802.11 frame includes a priority queue field to indicate a particular queue of a plurality of priority queues;

a first queue of the plurality of priority queues is associated with the first configured values; and

the data that indicates that the first data packet is associated with the first configured values is data in the priority queue field of the first data packet that indicates the first queue.

6. A method as recited in claim 5, wherein:

the second data packet is formatted as a frame of IEEE standard 802.11;

a different second queue of the plurality of priority queues is associated with the second configured values; and

said step of transmitting the second data packet further comprising inserting data that indicates the second queue in the priority queue field of the second data packet.

7. A method as recited in claim 1, wherein the second maximum wait interval is equal to a maximum wait interval for sending an acknowledgement data packet, whereby said step of transmitting the second data packet is performed instead of transmitting an acknowledgment data packet.

8. A method as recited in claim 7, wherein the second data packet includes data from the first data packet that uniquely identifies the first data packet to the sending node, whereby said step of transmitting the second data packet has an effect substantively equivalent to transmitting an acknowledgement data packet.

9. A method for transmitting data packets in a wireless mesh network, comprising the steps of:

transmitting over a wireless link a first data packet;

receiving next over the wireless link a second data packet after a particular time;

determining whether the particular time is within a maximum acknowledgement wait interval; and

if it is determined that the particular time is within the maximum acknowledgement wait interval, then determining that the first data packet is not transmitted again;

wherein

the second data packet is substantially similar to the first data packet, and

the second data packet is not an acknowledgment data packet that is short compared to the first data packet.

10. A method as recited in claim 9, wherein the first data packet is formatted as a frame of Institute of Electrical and Electronics Engineers (IEEE) standard 802.11.

11. A method as recited in claim 9, wherein the second data packet is formatted as a frame of Institute of Electrical and Electronics Engineers (IEEE) standard 802.11.

12. A method as recited in claim 9, said step of determining that the first data packet is not transmitted again further comprising the steps of:

determining whether data in a sequence field of the first data packet matches data in the sequence field of the second data packet; and

determining that the first data packet is not transmitted again only if it is determined that data in the sequence field of the first data packet matches data in the sequence field of the second data packet.

13. A method as recited in claim 9, wherein:

the second data packet is formatted as a frame of Institute of Electrical and Electronics Engineers (IEEE) standard 802.11;

the IEEE 802.11 frame includes a priority queue field to indicate a particular queue of a plurality of priority queues;

a high priority queue of the plurality of priority queues is associated with high priority transmission of the data packet over a backhaul of a wireless mesh network; and

said step of determining that the first data packet is not transmitted again further comprises the steps of;

determining whether data in the priority queue field of the second data packet indicates the high-priority queue; and

determining that the first data packet is not transmitted again only if it is determined that the data in the priority queue field of the second data packet indicates the high-priority queue.

14. An apparatus comprising:

means for receiving, over a wireless link at a wireless intermediate network node of a wireless mesh network, a first data packet that includes data that indicates that the first data packet was transmitted by a sending node that is one of a wireless end node and a wireless roof top access point connected by a wire to a wired subnetwork, wherein the first data packet is associated with first configured values for a first minimum wait interval and a first maximum wait interval for reducing contention for the wireless link; and

means for transmitting over the wireless link a second data packet based on the first data packet after a wait based on second configured values for a different second minimum wait interval and a different second maximum wait interval for reducing contention for the wireless link,

wherein the first minimum wait interval is greater than the second minimum wait interval.

15. An apparatus comprising:

means for transmitting over a wireless link a first data packet;

means for receiving next over the wireless link a second data packet after a particular time;

means for determining whether the particular time is within a maximum acknowledgement wait interval; and

means for determining that the first data packet is not transmitted again if it is determined that the particular time is within the maximum acknowledgement wait interval,

wherein

the second data packet is substantially similar to the first data packet, and

the second data packet is not an acknowledgment data packet that is short compared to the first data packet.

16. An apparatus comprising:

a wireless network interface that is in wireless communication with a packet-switched network for communicating therewith a data packet;

one or more processors;

a computer-readable medium; and

one or more sequences of instructions stored in the computer-readable medium, which, when executed by the one or more processors, causes the one or more processors to carry out the steps of;

receiving, over the wireless network interface, a first data packet that includes data that indicates that the first data packet was transmitted by a sending node that is one of a wireless end node and a wireless roof top access point connected by a wire to a wired subnetwork, wherein the first data packet is associated with first configured values for a first minimum wait interval and a first maximum wait interval for reducing contention for the wireless link; and

transmitting over the wireless network interface a second data packet based on the first data packet after a wait based on second configured values for a different second minimum wait interval and a different second maximum wait interval for reducing contention for the wireless link,

wherein the first minimum wait interval is greater than the second minimum wait interval.

17. An apparatus as recited in claim 16, wherein the first minimum wait interval is greater than the second maximum wait interval.

18. An apparatus as recited in claim 16, wherein:

execution of the one or more sequences of instructions further causes the one or more processors to carry out the step of determining a maximum hop time for a data packet to hop to an adjacent intermediate network node in the wireless mesh network; and

the second minimum wait interval is not less than the maximum hop time.

19. An apparatus as recited in claim 18, wherein the second minimum wait interval is substantively equal to the maximum hop time.

20. An apparatus comprising:

a wireless network interface that is in wireless communication with a packet-switched network for communicating therewith a data packet;

one or more processors;

a computer-readable medium; and

one or more sequences of instructions stored in the computer-readable medium, which, when executed by the one or more processors, causes the one or more processors to carry out the steps of;

transmitting a first data packet over a wireless network interface;

receiving next over the wireless network interface a second data packet after a particular time;

determining whether the particular time is within a maximum acknowledgement wait interval; and

if it is determined that the particular time is within the maximum acknowledgement wait interval, then determining that the first data packet is not transmitted again;

wherein

the second data packet is substantially similar to the first data packet, and

the second data packet is not an acknowledgment data packet that is short compared to the first data packet.