Optimizing 802.11 power-save for IP multicast groups

• US 8,457,028 B2
• Filed: 02/29/2008
• Issued: 06/04/2013
• 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: Griswold, Victor J., Meier, Robert
• Primary Examiner(s): Banks Harold, Marsha D
• Assistant Examiner(s): Houshmand, Hooman
• Application Number:
  US12/039,895
• Publication Number:
  US 20080144559A1
• Time in Patent Office: 1,922 Days
• Field of Search: None
• 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 Internet Protocol (IP) multicast group and a second IP multicast group;

the access point determines whether members of the first IP multicast group are in an active state or a power save state;

the access point determines whether members of the second IP multicast group are in an active state or a power save state;

wherein the access point receives a multicast packet for the first and second IP multicast groups;

wherein the access point is configured to send the multicast packet to the first multicast group without waiting for a beacon responsive to determining that none of the members of the first IP multicast group are currently in the power save state; and

wherein the access point is further configured to buffer the multicast packet and send the multicast packet to the second IP multicast group after a subsequent beacon responsive to determining that at least one member of the second IP multicast group is in the power save state.

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

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

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

5. 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.

6. 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.

7. 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.

8. 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.

9. The access point of claim 1, wherein the access point determines a member of the multicast group is unable to receive a frame if the member is in a power save mode.

10. A method, comprising:

determining members of a first Internet Protocol (IP) multicast group;

determining members of a second IP multicast group;

receiving a multicast packet for the first and IP multicast groups;

determining whether the members of the first IP multicast group are currently in an active state or a power save state;

determining whether members of the second IP multicast group are currently in the active state or the power save state;

sending the multicast packet to the first IP multicast group without waiting for a beacon responsive to determining that none of the members of the first IP multicast group are in the power save state; and

buffering and sending the packet after a subsequent beacon to the second IP multicast group responsive to determining a member of the second IP multicast group is unable to receive the second multicast packet.

11. The method of claim 10, wherein a plurality of mobile devices belong to the first IP multicast group, the method further comprising:

determining whether any members of the first IP multicast group are in a power save mode;

sending a multicast packet to the IP multicast group without waiting for a beacon responsive to determining none of the members of the IP multicast group are in the power save mode.

12. Logic encoded in a non-transitory tangible computer readable media for execution, and when executed operable to:

determine members of a first Internet Protocol (IP) multicast group;

determine members of a second IP multicast group;

receive a multicast packet for distribution to both first and IP multicast groups;

determine whether the members of the first IP multicast group are in an active state or a power save state;

determine whether members of the second IP multicast group are currently in the active state or the power save state;

send the multicast packet to the first IP multicast group without waiting for a beacon responsive to determining that no members of the first IP multicast group are in the power save state; and

buffer and send the packet after a subsequent beacon to the second multicast IP group responsive to determining a member of the second IP multicast group is in the power save state.