SEAMLESSLY SWITCHING OVERLAY NETWORK RELAY TREES

• US 20080317044A1
• Filed: 06/22/2007
• Published: 12/25/2008
• Est. Priority Date: 06/22/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Tang, Jian, Li, Jiang, Luo, Chong
• Granted Patent: US 7,839,798 B2
• Time in Patent Office: Days
• US Class Current: 370/397
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/42 Centralised routing
• CPC Class Codes: H04L 45/64 using an overlay routing layer
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 67/104 Peer-to-peer [P2P] networks
• CPC Class Codes: H04L 67/1089 Hierarchical topologies

Abstract

Technologies for switching a set of nodes in an overlay network from one relay tree configuration to another without duplicate packets or packet loss at any of the nodes. A commander node calculates a new relay tree as well as a media stream set configuration for each node in the overlay network, each media stream set corresponding to the new relay tree. Media stream sets include a unique version number or the like that identifies the specific relay tree configuration of which they are a part. Also provided are technologies for associating a media stream with a particular relay tree configuration and the corresponding media stream set of each node in the overlay network.

Claims

1. A relay tree management system comprising:

a media stream set calculator operable to calculate a media stream set configuration for each node of an overlay network, each media stream set configuration based on a new relay tree configuration for the overlay network and each media stream set configuration including a version number corresponding to the new relay tree configuration;

a means of sending each media stream set configuration to the corresponding node of the overlay network; and

a means of receiving an acknowledgment from each node of the overlay network responsive to the sent media stream set configuration, each acknowledgment indicating that the corresponding node of the overlay network successfully received the sent media stream set configuration and established communications with other nodes identified by the sent media stream set configuration.

2. The system of claim 1 further comprising a means of sending a switch command to a source node of the new relay tree configuration, the switch command including the version number corresponding to the new relay tree configuration, the switch command being sent after each acknowledgement is received from each corresponding node of the overlay network.

3. The system of claim 1 further comprising:

a means of receiving the media stream set configuration;

a media stream set creator operable to create a media stream set based on the received media stream set configuration; and

a media stream set router operable to route data packets based on the created media stream set.

4. The system of claim 3 wherein the media stream set router is operable to forward the data packets to an application.

5. The system of claim 3 further comprising a media stream set deleter operable to delete a media stream set that is no longer in use.

6. The system of claim 5 wherein the media stream set deleter deletes an older media stream set when sequence numbers of older data packets corresponding to the older media stream set precede a further sequence number of a first data packet corresponding to the media stream set.

7. A method for switching the nodes of an overlay network from an old relay tree configuration to a new relay tree configuration without causing duplicate or lost data packets at the nodes, the method comprising:

calculating the new relay tree;

calculating a media stream set configuration for each of the nodes, each media stream set configuration based on the new relay tree and including a version number corresponding to the new relay tree configuration; and

sending each media stream set configuration to the corresponding node.

8. The method of claim 7 further comprising:

receiving an acknowledgment from each of the nodes, each acknowledgment indicating that the corresponding node of the overlay network successfully received the sent media stream set configuration and established communications with other nodes identified by the sent media stream set configuration; and

sending a switch command to a source node of the new relay tree, the switch command including a version number of the new relay tree.

9. The method of claim 8 wherein the source node, after receiving the switch command, associates a next data packet with the new relay tree.

10. The method of claim 8 wherein data packets sent from the source node are associated with the new relay tree.

11. The method of claim 8 embodied as computer-executable instructions stored on a computer-readable medium.

12. A method of creating a new media stream set and deleting an old media stream set on a node, the method comprising:

receiving a new media stream set configuration from a commander node, the new media stream set configuration associated with a new relay tree;

creating a new media stream set on the node based on the new media stream set configuration; and

establishing communications with other nodes as specified by the new media stream set wherein incoming data packets that are associated with the new media stream set are routed to the other nodes as indicated by the new media stream set.

13. The method of claim 12 further comprising returning an acknowledgement to the commander node, the acknowledgement indicating successfully receiving the new media stream set configuration and creating the new media stream set and establishing communications with other nodes as specified by the new media stream set.

14. The method of claim 13 further comprising waiting until old data packets associated with the old media stream set have been received and then deleting the old media stream set.

15. The method of claim 14 wherein the waiting includes determining when sequence numbers of the old data packets corresponding to the old media stream set precede a further sequence number of a first data packet corresponding to the new media stream set.

16. The method of claim 12 wherein the new media stream set associates port numbers with the new relay tree.

17. The method of claim 16 wherein data packets associated with the new relay tree are forwarded to the other nodes as specified by the new media stream set via the port numbers indicated by the new media stream set.

18. The method of claim 16 wherein the port numbers are used to distinguish between the new relay tree and the old relay tree and any other relay trees.

19. The method of claim 12 wherein the new media stream set configuration is associated with the new relay tree using a version number.

20. The method of claim 12 embodied as computer-executable instructions stored on a computer-readable medium.