Multicast distribution over one or more addressable buses wherein a switch includes a remapping table for inputting address for one or more destinations

• US 7,581,038 B1
• Filed: 03/16/2006
• Issued: 08/25/2009
• Est. Priority Date: 03/16/2006
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Polycom Incorporated (HP Inc.)
• Inventors: Lieberman, Noam, Ozalvo, Shlomi, Bourshtein, Nathan, Sity, Rafi
• Primary Examiner(s): PEYTON, TAMMARA R
• Application Number:
  US11/378,797
• Time in Patent Office: 1,258 Days
• Field of Search: 710/8, 710/10, 710/33, 709/200, 709/227
• US Class Current: 710/9
• CPC Class Codes: G06F 13/4022 using switching circuits, e.g. switching matrix, connection or expansion network G06F13/4009 takes precedence
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04N 7/152 Multipoint control units therefor

Abstract

Disclosed herein is a method for multicasting data to a plurality of destinations over an addressable bus using a switch adapted to receive a stream of data cells from a data source. The switch is adapted to determine the appropriate recipients of the data using a stream identifier associated with the data cells, replicate the data for each destination, and send the replicated data to each destination. The data source need not be aware of the recipient of the data stream because the recipient is determined by the switch. The stream from the data source can be sent to a different set of recipients by associating the new recipients with the stream identifier. This method is useful for applications such as videoconferencing, in which groups of recipients of a particular data stream change often.

Claims

1. A method of delivering at least one data stream comprising a plurality of data cells from a logical module to one or more destinations via one or more addressable buses, the method comprising:

assigning a stream identifier to the at least one data stream;

associating the data cells with the stream identifier;

delivering the data cells toward a switch over one of the addressable buses;

identifying, at the switch, an inputting address for each one or more destinations associated with each stream identifier, and

for each destination, replicating a payload of the data cells and delivering the replicated payload to the inputting address of the destination via one or more addressable buses.

2. The method of claim 1, further comprising modifying the identified inputting address wherein delivering the replicated payload is toward the modified inputting address.

3. The method of claim 2, wherein the modification to the inputting address reflects the location of the cell within a frame of data.

4. The method of claim 2, wherein the modification is done by adding an offset value to the inputting address.

5. The method of claim 1, wherein identifying one or more destinations associated with a stream identifier comprises retrieving an entry associated with the stream identifier from a remapping table.

6. The method of claim 1, wherein, wherein the stream identifier further comprises an indication that a given cell is one of a stream of consecutive cells constituting a frame of data.

7. The method of claim 1, wherein the destination associated with the stream identifier comprises a space of inputting addresses for receiving the stream of consecutive cells constituting a frame of data.

8. The method of claim 1, further comprising updating the remapping table by changing the destination addresses associated with the stream identifier.

9. The method of claim 1, wherein at least one addressable bus is a PCI bus.

10. The method of claim 1, wherein the logical module is a digital signal processor (DSP).

11. The method of claim 1, wherein the logical module is process running in a DSP.

12. The method of claim 10, wherein the DSP is part of a multipoint control unit (MCU).

13. The method of claim 1, wherein data stream comprises video or audio data.

14. The method of claim 1, wherein at least one destination receives cells associated with two or more different stream identifiers.

15. The method of claim 1, wherein at least one destination is associated with two or more inputting addresses.

16. The method of claim 1, wherein the inputting address is a space of memory addresses that is associated with the destination logical module.

17. A switch for delivering a data stream comprising a plurality of data cells from a logical module to one or more destinations via one or more addressable buses, wherein the data stream is associated with a stream identifier, the switch comprising:

a remapping table comprising an entry corresponding to the stream identifier, the entry comprising a list of an inputting address for each of the one or more destinations associated with the stream identifier; and

a replicator module adapted to;

modify the inputting address to reflect the location of the cell within a frame of data;

replicate a payload of the data cells;

and deliver the replicated payload to the modified inputting address of the destination via the one or more addressable busses.

18. A MCU comprising a switch adapted to deliver a data stream comprising a plurality of data cells from a digital signal processor (DSP) to one or more destinations via one or more addressable buses, the switch comprising a remapping table adapted to recognize a stream identifier associated with the data stream and identify one or more destination addresses associated with the stream identifier;

and a replicator module adapted to modify the inputting address to reflect the location of the cell within a frame of data, replicate a payload of the data cells and deliver the replicated payload to the modified destination addresses via the one or more addressable busses.

19. The MCU of claim 18, wherein the remapping table comprises an entry corresponding to the stream identifier, the entry comprising a list of one or more destination addresses associated with the stream identifier.

20. The MCU of claim 19, wherein the remapping table is adapted to be updated during a videoconference by changing one or more destination addresses associated with the stream identifier.

21. The MCU of claim 20, wherein the updating is in response to changing speakers during a video conference.