Direct link setup mechanisms for wireless LANs

• US 8,432,920 B2
• Filed: 09/19/2006
• Issued: 04/30/2013
• Est. Priority Date: 09/19/2006
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell World Trade Limited (Marvell Technology Group Limited)
• Inventors: Yee, James, Goel, Sandesh, Kopikare, Milind, Chen, James Chieh-Tsung
• Primary Examiner(s): PHUONG, DAI
• Application Number:
  US11/523,407
• Publication Number:
  US 20080069047A1
• Time in Patent Office: 2,415 Days
• Field of Search: 370/338, 370/328
• US Class Current: 370/395.4
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Apparatus having corresponding methods and computer programs comprise a communication circuit to establish an infrastructure mode wireless connection with a wireless client through a wireless access point, and to establish a direct link setup (DLS) mode wireless connection with the wireless client; and a control circuit to select either infrastructure mode or DLS mode for communication with the wireless client based on at least one characteristic of the infrastructure mode and DLS mode wireless connections; wherein the communication circuit exchanges frames of data with the wireless client using the selected mode.

Claims

1. A client station comprising:

a communication circuit of the client station to

establish an infrastructure mode wireless connection with a wireless client through a wireless access point, and

establish a direct link setup (DLS) mode wireless connection with the wireless client; and

a control circuit of the client station to

select either an infrastructure mode or a DLS mode for communication with the wireless client based on at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection, and

cause the client station to enter a power save mode when the DLS mode is selected,

wherein the communication circuit exchanges frames of data with the wireless client using the selected mode,

wherein the control circuit negotiates a communications schedule directly with the wireless client based on a common timer synchronization function (TSF) received from beacon signals transmitted by the wireless access point,

wherein the communications schedule includes a series of communication windows for communication between the client station and the wireless client using the DLS mode wireless connection,

wherein the communication windows are separated by fixed time intervals,

wherein the communications schedule specifies a start time and a communication interval, and

wherein the client station and the wireless client leave the power save mode at the start time, communicate during one of the communication windows, and then resume the power save mode.

2. The client station of claim 1, wherein the at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection comprises at least one of a group consisting of:

a quality of service of the infrastructure mode wireless connection and the DLS mode wireless connection;

a power consumption of the infrastructure mode wireless connection and the DLS mode wireless connection;

a received signal strength of the infrastructure mode wireless connection and the DLS mode wireless connection;

a time required to send a frame over the infrastructure mode wireless connection and the DLS mode wireless connection;

a maximum data rate of the infrastructure mode wireless connection and the DLS mode wireless connection; and

a packet loss rate of the infrastructure mode wireless connection and the DLS mode wireless connection.

3. The client station of claim 1:

wherein the communication circuit receives a message from the wireless access point, wherein the message identifies a media access control (MAC) address of the wireless client; and

wherein the control circuit identifies the wireless client based on the message.

4. The client station of claim 3:

wherein the message indicates whether the wireless client is capable of establishing the DLS mode wireless connection.

5. The client station of claim 3:

wherein, before receiving the message from the wireless access point, the communication circuit transmits a further message to the wireless access point, wherein the further message identifies one or more data stream types supported by the client station; and

wherein the message received from the wireless access point identifies the wireless client when the wireless client supports the one or more data stream types supported by the client station.

6. The client station of claim 1:

wherein the control circuit identifies the wireless client by collecting destination media access control (MAC) addresses in frames transmitted by the wireless access point.

7. The client station of claim 1:

wherein the control circuit, after selecting the DLS mode for the wireless client, selects the infrastructure mode for the wireless client in response to an event.

8. The client station of claim 7, wherein the event is selected from a group consisting of:

a received signal strength of the DLS mode wireless connection with the wireless client falls below a predetermined threshold; and

the control circuit detects no frames addressed to the wireless client during a predetermined interval.

9. The client station of claim 1:

wherein the control circuit determines proximity information for the wireless client, and selects the wireless client for the DLS mode wireless connection based on the proximity information.

10. The client station of claim 1:

wherein the communication circuit establishes the infrastructure mode wireless connection on a first channel;

wherein the communication circuit establishes the DLS mode wireless connection on a second channel; and

wherein the control circuit selects the second channel when selecting the DLS mode.

11. The client station of claim 1:

wherein the control circuit causes the client station to enter the power save mode;

wherein the communication circuit receives the beacon signals from the wireless access point while the client station is in the power save mode; and

wherein after every Nth one of the beacon signals, wherein N>

0, the control circuit causes the client station to leave the power save mode, then the communication circuit communicates with the wireless client when the DLS mode has been selected using the DLS mode wireless connection, and then the control circuit causes the client station to enter the power save mode again based on the communications schedule.

12. The client station of claim 11:

wherein the wireless client, when the DLS mode has been selected, receives the beacon signals, leaves the power save mode when the control circuit causes the client station to leave the power save mode, and enters the power save mode when the control circuit causes the client station to enter the power save mode.

13. The client station of claim 11:

wherein the communication circuit transmits a message to the wireless access point informing the wireless access point that the client station is entering the power save mode.

14. The client station of claim 1:

wherein the communication circuit and the wireless client, when the DLS mode has been selected, receive the beacon signals from the wireless access point;

wherein the control circuit causes the client station to leave the power save mode, and then the communication circuit establishes the DLS mode wireless connection with the wireless client, based on the communications schedule; and

wherein the wireless client leaves the power save mode, and establishes the DLS mode wireless connection with the client station, based on the communications schedule.

15. The client station of claim 14:

wherein the communication circuit transmits a message to the wireless access point informing the wireless access point that the client station is entering the power save mode.

16. The client station of claim 1 comprising a media access controller (MAC), wherein the MAC includes the communication circuit and the control circuit.

17. The client station of claim 16 comprising an integrated circuit (IC), wherein the IC includes the MAC.

18. The client station of claim 1, wherein the client station is compliant with all or part of IEEE standard 802.11, including draft and approved amendments 802.11a, 802.11b, 802.11e, 802.11g, 802.11i, 802.11k, 802.11n, 802.11v, and 802.11w.

19. A client station comprising:

communication means of the client station for

establishing an infrastructure mode wireless connection with a wireless client through a wireless access point, and

establishing a direct link setup (DLS) mode wireless connection with the wireless client; and

control means of the client station for

selecting either an infrastructure mode or a DLS mode for communication with the wireless client based on at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection, and

causing the client station to enter power a save mode when the DLS mode is selected,

wherein the communication means exchanges frames of data with the wireless client using the selected mode,

wherein the control means negotiates a communications schedule directly with the wireless client based on a common timer synchronization function (TSF) received from beacon signals transmitted by the wireless access point,

wherein the communications schedule includes a series of communication windows for communication between the client station and the wireless client using the DLS mode wireless connection,

wherein the communication windows are separated by fixed time intervals,

wherein the communications schedule specifies a start time and a communication interval, and

wherein the client station and the wireless client leave the power save mode at the start time, communicate during one of the communication windows, and then resume the power save mode.

20. The client station of claim 19, wherein the at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection comprises at least one of a group consisting of:

a quality of service of the infrastructure mode wireless connection and the DLS mode wireless connection;

a power consumption of the infrastructure mode wireless connection and the DLS mode wireless connection;

a received signal strength of the infrastructure mode wireless connection and the DLS mode wireless connection;

a time required to send a frame over the infrastructure mode wireless connection and the DLS mode wireless connection;

a maximum data rate of the infrastructure mode wireless connection and the DLS mode wireless connection; and

a packet loss rate of the infrastructure mode wireless connection and the DLS mode wireless connection.

21. The client station of claim 19:

wherein the communication means receives a message from the wireless access point, wherein the message identifies a media access control (MAC) address of the wireless client; and

wherein the control means identifies the wireless client based on the message.

22. The client station of claim 21:

wherein the message indicates whether the wireless client is capable of establishing the DLS mode wireless connection.

23. The client station of claim 21:

wherein, before receiving the message from the wireless access point, the communication means transmits a further message to the wireless access point, wherein the further message identifies one or more data stream types supported by the client station; and

wherein the message received from the wireless access point identifies the wireless client when the wireless client supports the one or more data stream types supported by the client station.

24. The client station of claim 19:

wherein the control means identifies the wireless client by collecting destination media access control (MAC) addresses in frames transmitted by the wireless access point.

25. The client station of claim 19:

wherein the control means, after selecting the DLS mode for the wireless client, selects the infrastructure mode for the wireless client in response to an event.

26. The client station of claim 25, wherein the event is selected from a group consisting of:

a received signal strength of the DLS mode wireless connection with the wireless client falls below a predetermined threshold; and

the control means detects no frames addressed to the wireless client during a predetermined interval.

27. The client station of claim 19:

wherein the control means determines proximity information for the wireless client, and selects the wireless client for the DLS mode wireless connection based on the proximity information.

28. The client station of claim 19:

wherein the communication means establishes the infrastructure mode wireless connection on a first channel;

wherein the communication means establishes the DLS mode wireless connection on a second channel; and

wherein the control means selects the second channel when selecting the DLS mode.

29. The client station of claim 19:

wherein the control means causes the client station to enter the power save mode;

wherein the communication means receives the beacon signals from the wireless access point while the client station is in the power save mode; and

wherein after every Nth one of the beacon signals, wherein N>

0, the control means causes the client station to leave the power save mode, then the communication means communicates with the wireless client when the DLS mode has been selected using the DLS mode wireless connection, and then the control means causes the client station to enter the power save mode again based on the communications schedule.

30. The client station of claim 29:

wherein the wireless client, when the DLS mode has been selected, receives the beacon signals, leaves the power save mode when the control means causes the client station to leave the power save mode, and enters the power save mode when the control means causes the client station to enter the power save mode.

31. The client station of claim 29:

wherein the communication means transmits a message to the wireless access point informing the wireless access point that the client station is entering the power save mode.

32. The client station of claim 19:

wherein the communication means and the wireless client, when DLS mode has been selected, receive the beacon signals from the wireless access point;

wherein the control means causes the client station to leave the power save mode, and then the communication means establishes the DLS mode wireless connection with the wireless client, based on the communications schedule; and

wherein the wireless client leaves the power save mode, and establishes the DLS mode wireless connection with the client station, based on the communications schedule.

33. The client station of claim 32:

wherein the communication means transmits a message to the wireless access point informing the wireless access point that the client station is entering the power save mode.

34. The client station of claim 19 comprising a media access controller (MAC), wherein the MAC includes the communication means and the control means.

35. The client station of claim 34 comprising an integrated circuit (IC), wherein the IC includes the MAC.

36. The client station of claim 19, wherein the client station is compliant with all or part of IEEE standard 802.11, including draft and approved amendments 802.11a, 802.11b, 802.11e, 802.11g, 802.11i, 802.11k, 802.11n, 802.11v, and 802.11w.

37. A method comprising:

establishing an infrastructure mode wireless connection between a client station and a wireless client through a wireless access point, and establishing a direct link setup (DLS) mode wireless connection between the client station and the wireless client;

negotiating a communications schedule directly with the wireless client based on a common timer synchronization function (TSF) received from beacon signals transmitted by the wireless access point;

selecting either an infrastructure mode or a DLS mode for communication with the wireless client based at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection, and causing the client station to enter a power save mode when the DLS mode is selected based on the communications schedule; and

then

exchanging frames of data with the wireless client using the selected mode,

wherein the communications schedule includes a series of communication windows for communication between the client station and the wireless client using the DLS mode wireless connection,

wherein the communication windows are separated by fixed time intervals,

wherein the communications schedule specifies a start time and a communication interval, and

wherein the client station and the wireless client leave the power save mode at the start time, communicate during one of the communication windows, and then resume the power save mode.

38. The method of claim 37, wherein the at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection comprises at least one of a group consisting of:

a quality of service of the infrastructure mode wireless connection and the DLS mode wireless connection;

a power consumption of the infrastructure mode wireless connection and the DLS mode wireless connection;

a received signal strength of the infrastructure mode wireless connection and the DLS mode wireless connection;

a time required to send a frame over the infrastructure mode wireless connection and the DLS mode wireless connection;

a maximum data rate of the infrastructure mode wireless connection and the DLS mode wireless connection; and

a packet loss rate of the infrastructure mode wireless connection and the DLS mode wireless connection.

39. The method of claim 37, further comprising:

identifying the wireless client by receiving a message from the wireless access point, wherein the message identifies a MAC address of the wireless client.

40. The method of claim 39:

wherein the message indicates whether the wireless client is capable of establishing the DLS mode wireless connection.

41. The method of claim 39, further comprising:

before receiving the message from the wireless access point, transmitting a further message to the wireless access point, wherein the further message identifies one or more data stream types,

wherein the message received from the wireless access point identifies the wireless client when the wireless client supports the one or more data stream types.

42. The method of claim 37, further comprising:

identifying the wireless client by collecting destination MAC addresses in frames transmitted by the wireless access point.

43. The method of claim 37, further comprising:

after selecting the DLS mode for the wireless client, selecting the infrastructure mode for the wireless client in response to an event.

44. The method of claim 43, wherein the event is selected from a group consisting of:

a received signal strength of the DLS mode wireless connection with the wireless client falls below a predetermined threshold; and

no frames addressed to the wireless client are detected during a predetermined interval.

45. The method of claim 37, further comprising:

determining proximity information for the wireless client; and

selecting the wireless client for the DLS mode wireless connection based on the proximity information.

46. The method of claim 37, further comprising:

establishing the infrastructure mode wireless connection on a first channel;

establishing the DLS mode wireless connection on a second channel; and

selecting the second channel when selecting the DLS mode.

47. The method of claim 37, further comprising:

entering the power save mode;

receiving the beacon signals from the wireless access point while in the power save mode; and

after every Nth one of the beacon signals, wherein N>

0, leaving the power save mode, then communicating with the wireless client when the DLS mode has been selected using the DLS mode wireless connection, and then entering the power save mode again based on the communications schedule.

48. The method of claim 47:

wherein the wireless client, when the DLS mode has been selected, receives the beacon signals, leaves the power save mode when the method leaves the power save mode, and enters power save mode when the method enters the power save mode.

49. The method of claim 37, further comprising:

receiving the beacon signals from the wireless access point, wherein the wireless client, when the DLS mode has been selected, receives the beacon signals from the wireless access point; and

leaving the power save mode, and establishing the DLS mode wireless connection with the wireless client, based on the communications schedule,

wherein the wireless client leaves the power save mode, and establishes the DLS mode wireless connection, based on the communications schedule.

50. A computer program that is tangibly stored on a computer-readable medium and is executable by a processor, the computer program comprising instructions for:

establishing an infrastructure mode wireless connection between a client station and a wireless client through a wireless access point, and for establishing a direct link setup (DLS) mode wireless connection between the client station and the wireless client;

negotiating a communications schedule directly with the wireless client based on a common timer synchronization function (TSF) received from beacon signals transmitted by the wireless access point;

selecting either an infrastructure mode or a DLS mode for communication with the wireless client based at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection, and for causing the client station to enter a power save mode when the DLS mode is selected based on the communications schedule; and

then

exchanging frames of data with the wireless client using the selected mode,

wherein the communications schedule includes a series of communication windows for communication between the client station and the wireless client using the DLS mode wireless connection,

wherein the communication windows are separated by fixed time intervals,

wherein the communications schedule specifies a start time and a communication interval, and

wherein the client station and the wireless client leave the power save mode at the start time, communicate during one of the communication windows, and then resume the power save mode.

51. The computer program of claim 50, wherein the at least one characteristic of the infrastructure mode wireless connection and the DLS mode wireless connection comprises at least one of a group consisting of:

a quality of service of the infrastructure mode wireless connection and the DLS mode wireless connection;

a power consumption of the infrastructure mode wireless connection and the DLS mode wireless connection;

a received signal strength of the infrastructure mode wireless connection and the DLS mode wireless connection;

a time required to send a frame over the infrastructure mode wireless connection and the DLS mode wireless connection;

a maximum data rate of the infrastructure mode wireless connection and the DLS mode wireless connection; and

a packet loss rate of the infrastructure mode wireless connection and the DLS mode wireless connection.

52. The computer program of claim 50, further comprising:

instructions for identifying the wireless client according to a message received from the wireless access point, wherein the message identifies a MAC address of the wireless client.

53. The computer program of claim 52:

wherein the message indicates whether the wireless client is capable of establishing the DLS mode wireless connection.

54. The computer program of claim 52, further comprising:

instructions for transmitting a further message to the wireless access point, wherein the further message that identifies one or more data stream types before receiving the message from the wireless access point,

wherein the message received from the wireless access point identifies the wireless client when the wireless client supports the one or more data stream types.

55. The computer program of claim 50, further comprising:

instructions for identifying the wireless client by collecting destination MAC addresses in frames transmitted by the wireless access point.

56. The computer program of claim 50, further comprising:

instructions for selecting the infrastructure mode for the wireless client in response to an event after selecting the DLS mode for the wireless client.

57. The computer program of claim 56, wherein the event is selected from a group consisting of:

a received signal strength of the DLS mode wireless connection with the wireless client falls below a predetermined threshold; and

no frames addressed to the wireless client are detected during a predetermined interval.

58. The computer program of claim 50, further comprising:

instructions for determining proximity information for the wireless client; and

instructions for selecting the wireless client for the DLS mode wireless connection based on the proximity information.

59. The computer program of claim 50, further comprising:

instructions for establishing the infrastructure mode wireless connection on a first channel;

instructions for establishing the DLS mode wireless connection on a second channel; and

instructions for selecting the second channel when selecting the DLS mode.

60. The computer program of claim 50, further comprising:

instructions for entering the power save mode, wherein the beacon signals are received from the wireless access point while in the power save mode; and

instructions for, after every Nth one of the beacon signals, wherein N>

0, leaving the power save mode, then communicating with the wireless client when the DLS mode has been selected using the DLS mode wireless connection, and then entering the power save mode again.

61. The computer program of claim 60:

wherein the wireless client, when the DLS mode has been selected, receives the beacon signals, leaves the power save mode when the computer program leaves the power save mode, and enters power save mode when the computer program enters the power save mode.

62. The computer program of claim 50, further comprising:

wherein the beacon signals are received from the wireless access point, and wherein the wireless client, when the DLS mode has been selected, receives the beacon signals from the wireless access point; and

instructions for leaving the power save mode, and establishing the DLS mode wireless connection with the wireless client, based on the communications schedule,

wherein the wireless client leaves the power save mode, and establishes the DLS mode wireless connection, based on the communications schedule.