Optimizing 802.11 power-save for IP multicast groups

• US 20050114537A1
• Filed: 11/26/2003
• Published: 05/26/2005
• Est. Priority Date: 11/26/2003
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Meier, Robert, Griswold, Victor J.
• Granted Patent: US 7,362,757 B2
• Time in Patent Office: Days
• US Class Current: 709/231
• CPC Class Codes: H04L 12/12 Arrangements for remote connection or disconnection of substations or of equipment thereof
• CPC Class Codes: H04L 12/1827 Network arrangements for conference optimisation or adaptation
• CPC Class Codes: H04L 12/1886 with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains
• CPC Class Codes: H04L 12/189 in combination with wireless systems selective distribution or broadcast in wireless communication networks H04W4/06
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/0215 based on user or device properties, e.g. MTC-capable devices services for machine-to-machine communication [M2M] or machine type communication [MTC] H04W4/70; wireless resource selection or allocation plan definition based on terminal or device properties H04W72/51
• CPC Class Codes: H04W 28/14 using intermediate storage
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for providing a superior quality of service for multicast data streams delivered over a wireless local area network. As Internet Protocol multicast data streams are received by an access point, the access point observes Internet Group Multicast Protocol registration messages to determine which of its associated stations subscribe to each multicast data stream. The access point then determines which of the multicast data streams it receives have only active subscribing stations as opposed to those data streams having at least one associated station operating in power-save mode. The access point will automatically transmit each multicast data stream having only active subscribers immediately to the associated active stations, while buffering the multicast data stream for which there is at least one associated station operating in power-save mode.

Claims

1. A method for an access point to provide superior quality of service to a plurality of associated stations by automatically optimizing delivery of a plurality of multicast data streams over a network, the steps comprising:

observing, at an access point, a registration message that originated from at least one associated station;

determining, from the registration message, a multicast data stream to which this associated station subscribes;

tracking the multicast data stream for which all associated stations subscribing to the steam support low packet-delivery latency; and

transmitting the multicast data stream immediately to all associated low-latency stations.

2. The method of claim 1 wherein the access point is an 802.11 access point.

3. The method of claim 1 wherein the registration is accomplished using Internet Group Multicast Protocol.

4. The method of claim 1 wherein each low-latency associated station is in 802.11 active operation.

5. The method of claim 1, further comprising the step of comparing the multicast data stream for which all associated stations subscribing to the stream support low packet-delivery latency with a multicast data stream for which at least one associated station subscribing to the stream supports only high packet-delivery latency.

6. The method of claim 5, wherein each high-latency associated station is in 802.11 power-save protocol operation.

7. The method of claim 6, further comprising the step of buffering the multicast data stream for which the at least one associated station is in power-save protocol operation.

8. The method of claim 1, wherein the multicast data stream is transmitted to a plurality of stations operating on the same virtual local area network.

9. The method of claim 1, wherein the multicast data stream is transmitted to a plurality of stations operating on a plurality of virtual local area networks.

10. The method of claim 1, wherein the immediately transmitting step is applied at the Internet Protocol level.

11. The method of claim 1, wherein the associated station is a portable personal computer.

12. The method of claim 1, wherein the associated station is a personal data assistant.

13. In a network comprising at least one access point, a plurality of associated stations and a plurality of multicast data streams, a system for enhancing quality of service to the plurality of associated stations by automatically optimizing delivery of the multicast data streams over the network, comprising:

means adapted for observing, at an access point, a registration message that originated from at least one associated station;

means adapted for determining a multicast data stream to which this associated station subscribes;

means adapted for tracking the multicast data stream for which all associated stations subscribing to the steam support low packet-delivery latency; and

means adapted for transmitting the multicast data stream immediately to all the associated low-latency stations.

14. The system of claim 13 wherein the access point is an 802.11 access point.

15. The system of claim 13 wherein the registration is accomplished using Internet Group Multicast Protocol.

16. The system of claim 13 wherein each low-latency associated station is in 802.11 active operation.

17. The system of claim 13, the further comprising means adapted for comparing the multicast data stream for which all associated stations subscribing to the stream support low packet-delivery latency with a multicast data stream for which at least one associated station subscribing to the stream supports only high packet-delivery latency.

18. The system of claim 17, wherein each high-latency associated station is in 802.11 power-save protocol operation.

19. The system of claim 18, the further comprising means adapted for buffering a multicast data stream for which at least one associated station subscribing to the stream supports only high packet-delivery latency.

20. The system of claim 13, wherein the multicast data stream is transmitted to a plurality of stations operating on the same virtual local area network.

21. The system of claim 13, wherein the multicast data stream is transmitted to a plurality of stations operating on a plurality of virtual local area networks.

22. The system of claim 13, wherein the means adapted for immediately transmitting is applied at the Internet Protocol level.

23. The system of claim 13, wherein the associated station is a portable personal computer.

24. The system of claim 13, wherein the associated station is a personal data assistant.

25. A computer program product having a computer readable medium having computer program logic recorded thereon for performing a method for an access point to provide superior quality of service to a plurality of associated stations by automatically optimizing delivery of a plurality of multicast data streams over a network, the steps comprising:

observing, at an access point, a registration message that originated from at least one associated station;

determining a multicast data stream to which the this associated station subscribes;

tracking the multicast data stream for which all associated stations subscribing to the steam support low packet-delivery latency; and

transmitting the multicast data stream immediately to all associated low-latency stations.

26. The method of claim 25 wherein the access point is an 802.11 access point.

27. The method of claim 25 wherein the registration is accomplished using Internet Group Multicast Protocol.

28. The system of claim 25 wherein each low-latency associated station is in 802.11 active operation.

29. The method of claim 25, the steps further comprising comparing the multicast data stream for which all associated stations subscribing to the stream support low packet-delivery latency with a multicast data stream for which at least one associated station subscribing to the stream supports only high packet-delivery latency.

30. The method of claim 29, wherein each high-latency associated station is in 802.11 power-save protocol operation.

31. The system of claim 30, the further comprising means adapted for buffering a multicast data stream for which at least one associated station subscribing to the stream supports only high packet-delivery latency.

32. The method of claim 25, wherein the multicast data stream is transmitted to a plurality of stations operating on the same virtual local area network.

33. The method of claim 25, wherein the multicast data stream is transmitted to a plurality of stations operating on a plurality of virtual local area networks.

34. The method of claim 25, wherein the immediately transmitting step is applied at the Internet Protocol level.

35. The method of claim 25, wherein the associated station is a portable personal computer.

36. The method of claim 25, wherein the associated station is a personal data assistant.