MULTICAST SYSTEM USING CLIENT FORWARDING

• US 20070147375A1
• Filed: 03/07/2007
• Published: 06/28/2007
• Est. Priority Date: 09/06/2000
• Status: Active Grant

• Current Assignee: Geoff Smith, Matt Regan, Michael G. Lee
• Original Assignee: Geoff Smith, Matt Regan, Michael G. Lee
• Inventors: Lee, Michael, Smith, Geoff, Regan, Matt
• Granted Patent: US 7,719,985 B2
• Time in Patent Office: Days
• US Class Current: 370/390
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/1854 with non-centralised forwarding system, e.g. chaincast

Abstract

A system and method are disclosed for multicasting information to a set of clients that includes transmitting the information to a primary client from a server and instructing the primary client to forward the information to a secondary client.

Claims

1. A method of adding a new client to a multicast group comprising:

receiving a request from the new client to subscribe to the multicast group;

selecting an existing client to transmit information to the new client based on the network locations of the new client and the existing client and a comparison of a performance parameter of the existing client with performance parameters of other existing clients.

2. A method of subscribing to a multicast group comprising:

sending a request to a server from a subscribing client to subscribe to the multicast group; and

receiving from the server an identifier of a transmitting client that will send data to the subscribing client; and

receiving the data from the transmitting client.

3. A method of redirecting a receiving multicast client from a failed transmitting client comprising:

receiving a message from the receiving client that information is not being received;

sending a message to the receiving client indicating a new source of the information; and

sending a message to the new source directing the new source to send the information to the receiving client.

4. A method of redirecting a receiving multicast client from a failed transmitting client as recited in claim 3 further including:

flagging a set of secondary receiving clients that are to receive the information from the receiving client so that the receiving client will not be failed in the event that a secondary receiving client sends a message indicating that information is not being received.

5. A method of redirecting a receiving multicast client from a failed transmitting client as recited in claim 3 further including:

sending a test message to the receiving client;

in the event that a valid response to the test message is not received, failing the receiving client and sending a message to a set of secondary receiving clients that are to receive the information from the receiving client that directs the secondary receiving clients to receive information from a new source.

6. A method of redirecting a receiving multicast client from a failed transmitting client as recited in claim 3 wherein the new source is a dedicated backup server that reliably sends information to redirected clients.

7. A method of redirecting a receiving multicast client from an under performing transmitting client comprising:

receiving a message from the receiving client indicating the rate that information is being received;

determining that the information rate falls below a performance standard;

sending a message to the receiving client indicating a new source of the information; and

sending a message to the new source directing the new source to send the information to the receiving client.