OPTIMIZING 802.11 POWER-SAVE FOR IP MULTICAST GROUPS

• US 20080144559A1
• Filed: 02/29/2008
• Published: 06/19/2008
• Est. Priority Date: 11/26/2003
• Status: Active Grant

• Current Assignee: Robert Meier, Victor J. Griswold
• Original Assignee: Robert Meier, Victor J. Griswold
• Inventors: Meier, Robert, Griswold, Victor J.
• Granted Patent: US 8,457,028 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• 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. An apparatus, comprising:

an access point configured to wirelessly communicate with at least one mobile device;

wherein the access point is configured to determine a multicast group membership for a first mobile device;

wherein the access point is configured to determine whether the first mobile device is currently able to accept a multicast packet for the multicast group responsive to receiving a packet for the multicast group;

wherein the access point is configured to immediately send the multicast packet responsive to determining the first mobile device is currently able to receive the multicast packet; and

wherein the access point is configured to buffer the packet and send the multicast packet after a subsequent beacon responsive to determining the first mobile device is currently unable to receive the multicast packet.

2. The apparatus of claim 1, wherein the access point is further configured to determine a multicast group membership for a second mobile device, wherein the second mobile device belongs to a same multicast group as the first mobile device;

wherein the access point is configured to determine whether the second mobile device is currently able to accept a multicast packet for the multicast group responsive to receiving a packet for the multicast group;

wherein the access point is configured to immediately send the multicast packet responsive to determining that both the first mobile device and second mobile device are currently able to receive the multicast packet; and

wherein the access point is configured to buffer the packet and send the multicast packet after a subsequent beacon responsive to determining that one of a group consisting of the first mobile device, the second mobile device and both the first mobile device and second mobile devices are currently unable to receive the multicast packet.

3. The apparatus of claim 1, wherein the access point is further configured to determine a second multicast group membership for a second mobile device;

wherein the access point is configured to determine whether the second mobile device is currently able to accept a multicast packet for the second multicast group responsive to receiving a second packet for the second multicast group;

wherein the access point is configured to immediately send the multicast packet for the first multicast group responsive to determining that the first mobile device is currently able to receive the multicast packet; and

wherein the access point is configured to buffer the packet and send the second multicast packet after a subsequent beacon responsive to determining that the second mobile device is currently unable to receive the multicast

4. The apparatus of claim 1, wherein the access point is further configured to determine a second multicast group membership for a second mobile device;

wherein the access point is configured to determine whether the second mobile device is currently able to accept a multicast packet for the second multicast group responsive to receiving a packet for the second multicast group;

wherein the access point is configured to immediately send the multicast packet for the first multicast group responsive to determining that the first mobile device is currently able to receive the multicast packet; and

wherein the access point is configured to immediately send the multicast packet for the second multicast group responsive to determining that the second mobile device is currently able to receive the multicast packet for the second multicast group.

5. The apparatus of claim 1, wherein the access point is configured to communicate with a plurality of mobile devices belonging to the multicast group;

wherein the access point is configured to determine whether any of the plurality of mobile devices belonging to the multicast group are in a power save mode responsive to receiving the packet for the multicast group;

wherein the access point is configured to immediately send the packet responsive to determining that none of the plurality of mobile devices are in the power save mode; and

wherein the access point is configured to buffer the packet and send the packet after a subsequent beacon responsive to determining at least one of the plurality of mobile devices is operating in the power save mode.

6. The apparatus of claim 5, wherein the access point is configured to communicate with a second plurality of mobile devices belonging to a second multicast group;

wherein the access point is configured to determine whether any of the second plurality of mobile devices belonging to the second multicast group are in the power save mode responsive to receiving a second packet for the second multicast group;

wherein the access point is configured to immediately send the second packet responsive to determining that none of the second plurality of mobile devices are in the power save mode; and

wherein the access point is configured to buffer the second packet and send the second packet after a subsequent beacon responsive to determining at least one of the second plurality of mobile devices is operating in the power save mode.

7. The apparatus of claim 1, wherein the access point is an 802.11 access point.

8. The apparatus of claim 1, wherein the access point determines the multicast group membership for the first mobile device by observing an Internet Multicast Group Protocol join request transmitted by the first mobile device.

9. The apparatus of claim 1, wherein the access point determines first mobile device is currently able to accept a multicast packet responsive to the first mobile device being a low-latency station.

10. The apparatus of claim 1, wherein the access point determines whether the first mobile device is currently able to accept the multicast packet by determining whether the first mobile device is operating in a power save mode.

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

12. The apparatus of claim 1, wherein a multicast data stream is transmitted to a plurality of stations operating on a plurality of virtual local area network.

13. The apparatus of claim 1, wherein the access point buffers the packet and sends the packet after a subsequent beacon responsive to determining at least one recipient of the packet supporting only high packet delivery latency.

14. The apparatus of claim 1, wherein the access point immediately sends the packet responsive to determining all recipients of the packet support only low packet delivery latency.

15. A method, comprising:

determining a multicast group membership for a first mobile device;

determining whether the first mobile device is currently able to receive a multicast packet for the multicast group responsive to receiving the multicast packet;

immediately sending the multicast packet responsive to determining the first mobile device is currently able to receive the multicast packet; and

buffering and sending the packet after a subsequent beacon responsive to determining the first device is unable to receive the multicast packet.

16. The method of claim 15, further comprising:

identifying a second mobile device belonging to the multicast group;

determining whether second mobile device is currently able to receive a multicast packet for the multicast group responsive to receiving the multicast packet;

immediately sending the multicast packet responsive to determining that both the first mobile device and second mobile device are currently able to receive the multicast packet; and

buffering and sending the packet after a subsequent beacon responsive to determining that at least one of the first mobile device and the second mobile device is unable to receive the multicast packet.

17. The method of claim 15, further comprising:

determining a second mobile device belongs to a second multicast group;

determining whether the second mobile device is currently able to receive a second multicast packet for the second multicast group;

immediately sending the second packet responsive to determining the second mobile device is able to receive the second packet.

18. The method of claim 15, further comprising:

determining a second mobile device belongs to a second multicast group;

determining whether the second mobile device is currently able to receive a second multicast packet for the second multicast group;

buffering and sending the second packet after a subsequent beacon responsive to determining the second mobile device is unable to receive the second packet.

19. The method of claim 15, wherein a plurality of mobile devices belong to the multicast group, the method further comprising:

determining whether any of the plurality of mobile devices are in a power save mode;

immediately sending a multicast packet for the multicast group responsive to determining none of the plurality of mobile devices are in the power save mode; and

buffering and sending the multicast packet for the multicast group responsive to determining that at least one of the plurality of mobile devices is in a power save mode.

20. The method of claim 19, further comprising:

determining a second plurality of mobile devices belonging to a second multicast group;

determining whether any of the second plurality of mobile devices belonging to the second multicast group are in the power save mode responsive to receiving a second packet for the second multicast group;

immediately sending the second packet responsive to determining that none of the second plurality of mobile devices are in the power save mode; and

buffering and sending the second packet after a subsequent beacon responsive to determining at least one of the second plurality of mobile devices is operating in the power save mode.