System and method for reliable multicast

• US 8,457,031 B2
• Filed: 01/11/2006
• Issued: 06/04/2013
• Est. Priority Date: 10/13/2005
• Status: Active Grant

• Current Assignee: Trapeze Networks Incorporated (Juniper Networks Incorporated)
• Original Assignee: Trapeze Networks Incorporated (Juniper Networks Incorporated)
• Inventors: Matta, Sudheer Poorna Chandra
• Primary Examiner(s): Hamza, Faruk
• Assistant Examiner(s): DECKER, CASSANDRA L
• Application Number:
  US11/330,877
• Publication Number:
  US 20070160046A1
• Time in Patent Office: 2,701 Days
• Field of Search: 370/312
• US Class Current: 370/312
• CPC Class Codes: H04L 12/1868 Measures taken after transmission, e.g. acknowledgments
• 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 43/12 Network monitoring probes
• CPC Class Codes: H04L 43/18 Protocol analysers
• CPC Class Codes: H04L 63/1408 by monitoring network traffic monitoring network traffic per se H04L43/00
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/06 Testing, supervising or monitoring using simulated traffic

Abstract

A technique for reliable multicast involves identifying a client as an acknowledger of a wireless multicast packet, and having the acknowledger acknowledge receipt of the multicast packet. An example of a method according to the technique may include receiving a multicast packet, selecting a client associated with a destination of the multicast packet, identifying the client in the multicast packet, forwarding the multicast packet to wireless, and retrying forwarding the multicast packet with the client identified in the multicast packet if no acknowledgement is received from the client. An example of a system according to the technique may include a means for identifying a client, a means for putting the client mac in the header of a multicast packet, a means for sending the multicast packet with the client mac to a wireless multicast destination, and a means for receiving acknowledgement from the client associated with the client mac.

Claims

1. A system, comprising:

an access point (AP) of a wireless AP (WAP) network configured to receive a multicast packet, the multicast packet having a header;

the access point configured to identify a single multicast packet recipient of a plurality of multicast packet recipients, the single multicast packet recipient being associated with a client MAC address and being the multicast packet recipient from the plurality of multicast packet recipients that is most recently associated with the access point;

the access point configured to add the client MAC address to the header of the multicast packet;

the access point configured to multicast, at a first data rate, the multicast packet with the client MAC address to a wireless multicast destination on the WAP network;

the access point configured to, if an acknowledgement from the single multicast packet recipient is not received within a time period, multicast, at a second data rate different from the first data rate, the multicast packet with the client MAC address to the wireless multicast destination on the WAP network; and

means for receiving at the AP acknowledgement from the single multicast packet recipient associated with the client MAC address.

2. The system of claim 1, wherein the multicast packet is an 802.11-compatible packet.

3. A system, comprising:

a client media access control (MAC) determination module configured to determine a MAC address associated with a single client device of a plurality of client devices, the single client device being selected from among the plurality of client devices based on a plurality of times, each time from the plurality of times corresponding to the association of a respective client device from the plurality of client devices with an access point (AP) on a wireless AP (WAP) network;

a multicast packet acknowledgement module configured to add the MAC address in a header of a multicast packet associated with a multicast destination that includes the client device;

the multicast packet acknowledgement module configured to receive acknowledgement that the multicast packet was received at the single client device;

an 802.11 MAC module; and

a processor configured to execute the client MAC determination module, the multicast packet acknowledgement module, and the 802.11 MAC module,

the processor configured to send the multicast packet, at a first data rate, from the AP to the single client device on the WAP network by multicasting the multicast packet on a wireless medium; and

the processor configured to send the multicast packet, if an acknowledgement from the single multicast packet recipient is not received within a time period, at a second data rate different from the first data rate, from the AP on the WAP network to the single client device on the WAP network by multicasting the multicast packet on the wireless medium.

4. The system of claim 3, wherein, after the MAC address has been added in the header of the multicast packet, the header of the multicast packet includes:

a multicast address;

a sender address;

a basic service set identifier (BSSID); and

a designated address identifying the single client device.

5. The system of claim 3, further comprising the client device having:

an acknowledgement module configured to;

read the MAC address in the header of the multicast packet; and

send an acknowledgement if the MAC address in the header of the multicast packet is identical to the single client device'"'"'s MAC address;

an 802.11 MAC module; and

a processor configured to execute the acknowledgement module and the 802.11 MAC module.

6. A method, comprising:

receiving a multicast packet at an access point (AP) of a wireless AP (WAP) network, the multicast packet having a header;

identifying a single multicast packet recipient of a plurality of multicast packet recipients, the single multicast packet recipient being associated with a client MAC address and being the multicast packet recipient from the plurality of multicast packet recipients that is most recently associated with the AP;

adding the client MAC address to the header of the multicast packet;

multicasting, at a first data rate, the multicast packet with the client MAC address to a wireless multicast destination on the WAP network; and

if an acknowledgment from the single multicast packet recipient is not received within a time period, multicasting, at a second data rate different from the first data rate, the multicast packet with the client MAC address to the wireless multicast destination on the WAP network; and

receiving at the AP acknowledgement from the single multicast packet recipient associated with the client MAC address.

7. The method of claim 6, wherein the multicast packet is an 802.11-compatible packet.