Content Management in Peer-to-Peer Content Distribution Clouds

• US 20090198825A1
• Filed: 04/05/2007
• Published: 08/06/2009
• Est. Priority Date: 05/19/2006
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Ranson, Stuart, Miller, John L., Gkantsidis, Christos, Rodriguez, Pablo Rodriguez, Garcia-Mendoza, Armando
• Granted Patent: US 8,090,861 B2
• Time in Patent Office: Days
• US Class Current: 709/230
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04L 67/108 characterised by resources being split in blocks or fragments

Abstract

Managing content by influencing its distribution in the form of blocks or other units is crucial to the performance of a peer-to-peer content distribution system. We provide a content management module at each peer node to achieve this. The content management module implements a content request/response cycle in order to negotiate about blocks of content with other peer nodes. This cycle comprises an offer request, offer reply and a block request. These steps are preferably followed by data exchange and verification. The negotiation protocol used by our content management module provides a generic method that is advantageously used in conjunction with different encoding schemes such as full network coding and group network coding. In one embodiment we use group network coding and add information to the offer request and offer reply to facilitate efficient content distribution. Block request messages are selected to promote the use of on-the-fly decoding where possible.

Claims

1. A method of negotiating which one or more blocks of content are to be exchanged between two peers in a peer to peer content distribution cloud the method comprising, at a peer node acting as a client node:

(i) sending an offer request message to another peer node acting as a server node to request an offer of one or more blocks of content available from that server node;

(ii) receiving an offer reply message from the server node comprising information about one or more blocks of content available from the server node;

(iii) selecting at least one block on the basis of the information in the offer reply message and sending a block request message to the server node to request the selected block(s);

and wherein the blocks are encoded using Group Network Coding and the offer request message comprises information about one or more groups the client node still needs content for.

2. A method as claimed in claim 1 wherein the offer reply message comprises information about only some of the total number of blocks of content available from the server.

3. A method as claimed in claim 1 wherein the offer request message comprises information which at least partially indicates those blocks of content that are already available to the client node.

4. A method as claimed in claim 1 wherein the offer request message comprises information which at least partially indicates those blocks of content that are required by the client node.

5. A method as claimed in claim 1 wherein the offer reply message comprises an offer for one or more groups that the client node still needs content for.

6. A method as claimed in claim 1 wherein the offer reply message comprises a plurality of offers for the same group.

7. A method as claimed in claim 5 wherein said step (iii) of selecting at least one block comprises, for each group, identifying those of the offered blocks which are innovative and wherein the method further comprises selecting one or more of the innovative blocks.

8. A method as claimed in claim 7 wherein the selection of the one or more innovative blocks is carried out on the basis of the amount of content already obtained for the group concerned.

12. A computer-readable medium containing steps of any of the preceding claims computer-executable instructions comprising:

(i) sending an offer request message to another peer node acting as a server node to request an offer of one or more blocks of content available from that server node;

(ii) receiving an offer reply message from the server node comprising information about one or more blocks of content available from the server node;

(iii) selecting at least one block on the basis of the information in the offer reply message and sending a block request message to the server node to request the selected block(s);

and wherein the blocks are encoded using Group Network Coding and the offer request message comprises information about one or more groups the client node still needs content for.

9. A method of negotiating which one or more blocks of content are to be exchanged between two peers in a peer to peer content distribution cloud the method comprising, at a peer node acting as a server node:

(i) receiving an offer request message from another peer node acting as a client node requesting an offer of one or more blocks of content available from the server node;

(ii) sending an offer reply message comprising information about one or more blocks of content available from the server node;

(iii) receiving a block request message from the client node requesting one or more selected ones of the offered blocks;

(iv) sending the requested block(s) to the client node; and

wherein the blocks are encoded using Group Network Coding and the offer request message comprises information about one or more groups the client node still needs content for.

10. A method as claimed in claim 9 wherein the offer reply message comprises an offer for one or more groups that the client node still needs content for.

11. A method as claimed in claim 9 wherein the offer reply message comprises a plurality of offers for the same group.

13. A computer-readable medium containing computer-executable instructions comprising:

(i) receiving an offer request message from another peer node acting as a client node requesting an offer of one or more blocks of content available from the server node;

(ii) sending an offer reply message comprising information about one or more blocks of content available from the server node;

(iii) receiving a block request message from the client node requesting one or more selected ones of the offered blocks;

(iv) sending the requested block(s) to the client node; and

wherein the blocks are encoded using Group Network Coding and the offer request message comprises information about one or more groups the client node still needs content for.

14. A peer node suitable for acting as a client node in a peer to peer content distribution cloud, and for negotiating which one or more blocks of content are to be exchanged between itself and another peer in the cloud using Group Network Coding the peer node comprising:

(i) means for sending an offer request message to another peer node acting as a server node to request an offer of one or more blocks of content available from that server node;

that offer request message comprising information about one or more groups the client node still needs content for;

(ii) means for receiving an offer reply message from the server node comprising information about one or more blocks of content available from the server node;

(iii) a processor arranged to select at least one block on the basis of the information in the offer reply message and to send a block request message to the server node to request the selected block(s).

15. A peer node as claimed in claim 14 wherein the means for receiving the offer reply message is arranged to receive offer reply messages comprising information about only some of the total number of blocks of content available from the server.

16. A peer node as claimed in claim 14 wherein the means for sending the offer request message is arranged to send offer request messages comprising information which at least partially indicates those blocks of content that are already available to the client node.

17. A peer node as claimed in claim 14 wherein the means for sending the offer request message is arranged to send offer request messages comprising information which at least partially indicates those blocks of content that are required by the client node.

18. A peer node as claimed in claim 14 wherein the means for receiving the offer reply message comprises means for receiving an offer for one or more groups that the client node still needs content for.

19. A peer node suitable for acting as a server node in a peer to peer content distribution cloud, and for negotiating which one or more blocks of content are to be exchanged between itself and another peer in the cloud using Group Network Coding the peer node comprising:

(i) means for receiving an offer request message from another peer node acting as a client node requesting an offer or one or more blocks of content available from the server node;

that offer request message comprising information about one or more groups the other peer node still needs content for;

(ii) means for sending an offer reply message comprising information about one or more blocks of content available from the server node;

(iii) means for receiving a block request message from the client node requesting one or more selected ones of the offered blocks; and

(iv) means for sending the requested block(s) to the client node.

20. A peer node as claimed in claim 19 wherein the information about one or more groups the other peer node still needs content for is provided as a bit vector.