Layered multicast and fair bandwidth allocation and packet prioritization

• US 7,733,868 B2
• Filed: 01/26/2006
• Issued: 06/08/2010
• Est. Priority Date: 01/26/2005
• Status: Active Grant

• Current Assignee: Scale Video Coding LLC (Equitable IP Corporation)
• Original Assignee: INTERNET BROADCASTING CORPORATION
• Inventors: Van Zijst, Erik
• Primary Examiner(s): Harper, Kevin C
• Assistant Examiner(s): Wong, Xavier Szewai
• Application Number:
  US11/342,167
• Publication Number:
  US 20060268871A1
• Time in Patent Office: 1,594 Days
• Field of Search: 370229-231, 370/235, 370/238, 370/389, 370/394, 370/428, 370/468, 370/469, 370/477, 370/390, 370430-432
• US Class Current: 370/394
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 1/1874 Buffer management
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 12/1836 with heterogeneous network architecture
• CPC Class Codes: H04L 12/1868 Measures taken after transmission, e.g. acknowledgments
• CPC Class Codes: H04L 12/1881 with schedule organisation, e.g. priority, sequence management
• CPC Class Codes: H04L 2101/604 Address structures or formats
• CPC Class Codes: H04L 43/0829 Packet loss
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/12 Shortest path evaluation
• CPC Class Codes: H04L 45/123 Evaluation of link metrics techniques for monitoring network metrics H04L43/08
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/18 Loop-free operations
• CPC Class Codes: H04L 45/302 Route determination based on requested QoS
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/64 using an overlay routing layer
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/11 Identifying congestion
• CPC Class Codes: H04L 47/125 : by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 47/15 : in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/2408 : for supporting different services, e.g. a differentiated services [DiffServ] type of service
• CPC Class Codes: H04L 47/2416 : Real-time traffic
• CPC Class Codes: H04L 47/2441 : relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/30 : in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/32 : by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 47/34 : ensuring sequence integrity, e.g. using sequence numbers
• CPC Class Codes: H04L 61/00 : Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/103 : across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
• CPC Class Codes: H04N 19/34 : Scalability techniques involving progressive bit-plane based encoding of the enhancement layer, e.g. fine granular scalability [FGS]
• CPC Class Codes: H04N 19/39 : involving multiple description coding [MDC], i.e. with separate layers being structured as independently decodable descriptions of input picture data
• CPC Class Codes: H04N 21/234327 : by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/23605 : Creation or processing of packetized elementary streams [PES]
• CPC Class Codes: H04N 21/2383 : Channel coding or modulation of digital bit-stream, e.g. QPSK modulation arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/2662 : Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/6125 : involving transmission via Internet transmission by internet of broadcast information H04H60/82
• CPC Class Codes: H04N 21/6405 : Multicasting data broadcast and multicast in packet switching networks H04L12/18
• CPC Class Codes: H04N 21/64322 : IP

Abstract

Embodiments include an overlay multicast network. The overlay multicast network may provide a set of features to ensure reliable and timely arrival of multicast data. The embodiments include a congestion control system that may prioritize designated layers of data within a data stream over other layers of the same data stream. Each data stream transmitted over the network may be given an equal share of the bandwidth. Addressing in routing tables maintained by routers may utilize summarized addressing based on the difference in location of the router and destination address. Summarization levels may be adjusted to minimize travel distances for packets in the network. Data from high priority data stream layers may also be retransmitted upon request from a destination machine to ensure reliable delivery of data.

Claims

1. A method comprising:

receiving data from a source in a single stream;

storing a sequence vector of a packet within the packet on an accessible storage device, wherein the sequence vector includes;

a layer identifier indicating a relative location of the packet within a hierarchy of virtual layers, and

a packet identifier of a most recently received packet in each virtual layer in the stream, the layer identifier further indicating an importance of the packet, wherein the importance of the packet reflects a priority of the packet and influences a probability that the packet is selected to be dropped;

forwarding the data to multiple concurrent receivers over a packet switched network via a network interface;

updating a reliable list of virtual layers based on the received data and the sequence vector of the packet;

detecting, by a processor in communications with the accessible storage device, inadequate bandwidth to transmit the stream to a destination; and

selecting a virtual layer of high priority packets from the hierarchy of virtual layers in the stream to forward to the destination based on the layer identifier and the reliable list.

2. The method of claim 1, wherein the data is live.

3. The method of claim 2, further comprising:

guaranteeing timely delivery of the data to the multiple concurrent receivers.

4. The method of claim 3, wherein the packet-switched network includes nodes with insufficient bandwidth.

5. The method of claim 1, further comprising:

labeling each packet in each virtual layer with an incrementing sequence number.

6. The method of claim 5, further comprising:

tracking a most recently used sequence number for each virtual layer.

7. The method of claim 1, further comprising:

inspecting the sequence vector in a packet to detect packet loss in a virtual layer.

8. The method of claim 1, further comprising:

dividing available bandwidth among a plurality of data streams, wherein a network router prioritizes forwarding of high priority virtual layers.

9. The method of claim 1, further comprising:

initiating a countdown timer for each missing packet within a virtual layer; and

sending a retransmission request to the source for each missing packet within the virtual layer.

10. The method of claim 1, further comprising:

delivering packets in an original order; and

maintaining a buffer to temporarily queue packets from a virtual layer to wait for a less recent missing packet to be retransmitted.

11. The method of claim 1, further comprising:

marking a virtual layer as irrecoverable if a countdown timer has run out for a packet in the virtual layer.

12. The method of claim 1, further comprising:

receiving a request from a destination for a packet from a virtual layer; and

retransmitting the packet to the destination.

13. The method of claim 12, further comprising:

forwarding the request toward the source after searching a local buffer for a copy of the packet and determining that packet is not found locally.

14. The method of claim 1, further comprising:

selecting a virtual layer of lower priority packets in the stream to forward if sufficient bandwidth is available to the destination.

15. The method of claim 1, further comprising:

discarding duplicate retransmission requests upon receipt.

16. The method of claim 1, wherein packets are stored in a central data structure accessible to receivers over a packet switched network.

17. The method of claim 16, wherein the central data structure stores a pointer to a unique packet within the central data structure.

18. The method of claim 1, wherein a packet delivery time causally depends on a receipt of packets referenced in the sequence vector.