METHOD OF CONTROLLING CONGESTION FOR WIRELESS COMMUNICATIONS

• US 20090180384A1
• Filed: 01/14/2008
• Published: 07/16/2009
• Est. Priority Date: 01/14/2008
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: Rudrapatna, Ashok N., Li, Shupeng, Ansari, Nirwan
• Granted Patent: US 8,040,802 B2
• Time in Patent Office: Days
• US Class Current: 370/235
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/11 Identifying congestion
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/27 Evaluation or update of window size, e.g. using information derived from acknowledged [ACK] packets
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04W 28/0231 based on communication conditions dynamic wireless traffic scheduling definition based on channel quality criteria H04W72/54
• CPC Class Codes: H04W 28/0289 Congestion control load shedding arrangements in network planning H04W16/08; performing reselection for handling the traffic H04W36/22; wireless traffic scheduling H04W72/12
• CPC Class Codes: H04W 28/12 using signalling between network elements
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]

Abstract

An exemplary method of controlling communications includes determining a total congestion window size for a router device. An allocation of at least a portion of the determined total congestion window size to allocated at least one mobile station that communicates with the router device over a wireless link is determined based on the determined total congestion window size. The determined allocation is then reported to a source of a communication intended for the at least one mobile station.

Claims

1. A method of controlling communications, comprising the steps of:

determining a total congestion window size for a router device;

determining an allocation of at least a portion of the determined total congestion window size to at least one mobile station that communicates with the router device over a wireless link; and

reporting the determined allocation over a hardwired communication line to a source of a communication intended for the at least one mobile station.

2. The method of claim 1, comprising

determining the total congestion window size based on a measured buffer level at the router device.

3. The method of claim 2, comprising

determining a current buffer occupancy level;

determining a difference between the current buffer occupancy level and a previously determined buffer occupancy level; and

adjusting the total congestion window size based on the determined difference.

4. The method of claim 3, comprising

decreasing a current total congestion window size relative to a previous total congestion window size when the current buffer occupancy level exceeds the previously determined buffer occupancy level.

5. The method of claim 1, comprising

determining the total congestion window size based on a desired buffer occupancy level at the router device.

6. The method of claim 1, comprising

updating the determined total congestion window size and the determined allocation at an update rate that is based on an average round trip time of a packet over the wireless link.

7. The method of claim 1, comprising

determining the allocation based on a proportional fair distribution of the total congestion window size among a plurality of mobile stations communicating with the router device.

8. The method of claim 1, comprising

determining the allocation based on a quality of the wireless link.

9. The method of claim 8, comprising

determining the allocation as a function of an average packet throughput on the wireless link and an average packet round trip delay on the wireless link.

10. The method of claim 1, comprising

reporting the determined allocation as an indication in a header of a transport control protocol acknowledgment from the router device.

11. The method of claim 1, comprising

communicating between the router device and a plurality of servers over a wired connection;

communicating between the router device and a plurality of mobile stations over a plurality of wireless links; and

reporting the determined allocation to the servers such that a server transmission to the router device corresponds to the allocation for a corresponding mobile station intended to receive the transmission.

12. A router device, comprising:

a first communication portion configured to communicate with at least one device over a hardwired connection;

a second communication portion configured to communicate with at least one mobile station over a wireless link; and

a congestion controller configured to

determine a total congestion window size for the router device;

determine an allocation of at least a portion of the determined total congestion window size to the at least one mobile station; and

report the determined allocation to a source of a communication intended for the at least one mobile station.

13. The router device of claim 12, wherein the controller is configured to determine the total congestion window size based on a measured buffer level at the router device.

14. The router device of claim 13, wherein the controller is configured to

determine a current buffer occupancy level;

determine a difference between the current buffer occupancy level and a previously determined buffer occupancy level; and

adjust the total congestion window size based on the determined difference.

15. The router device of claim 12, wherein the controller is configured to determine the total congestion window size based on a desired buffer occupancy level at the router device.

16. The router device of claim 12, wherein the controller is configured to update the determined total congestion window size and the determined allocation at an update rate that is based on an average round trip time of a packet over the wireless link.

17. The router device of claim 12, wherein the controller is configured to determine the allocation based on a quality of the wireless link.

18. The router device of claim 12, wherein the controller is configured to determine the allocation as a function of an average packet throughput on the wireless link, an average packet round trip delay on the wireless link and a maximum possible allocation per wireless link.

19. The router device of claim 12, wherein the controller transmits a transport control protocol acknowledgment over the hardwired connection and indicates the determined allocation in a header of the transport control protocol acknowledgment.

20. A method of communicating, comprising

transmitting a transmission to a router device at a rate based on a received indication of an available window of an intended recipient of the transmission, wherein the received indication corresponds to a determined allocation of at least a portion of a determined total congestion window size of the router device allocated to an intended recipient of the transmission.

21. A method of communicating, comprising

receiving a transmission from a router device at a mobile station over a wireless link, wherein the transmission is provided to the router device at a rate based on an allocation of at least a portion of a determined total congestion window size of the router device allocated to the mobile station.