Apparatus and methods for utilizing variable rate program streams in a network

• US 7,889,765 B2
• Filed: 11/30/2005
• Issued: 02/15/2011
• Est. Priority Date: 11/30/2005
• Status: Active Grant

• Current Assignee: Time Warner Cable Enterprises LLC (Charter Communications Incorporated)
• Original Assignee: Time Warner Cable Inc. (Charter Communications Incorporated)
• Inventors: Rieger, Remi, Brooks, Paul D.
• Primary Examiner(s): Sheikh; Ayaz R
• Assistant Examiner(s): Ho; Chuong T
• Application Number:
  US11/291,328
• Publication Number:
  US 20070121678A1
• Time in Patent Office: 1,903 Days
• Field of Search: 370/464, 370/465, 370/474, 370/476, 370/477, 370/479, 370/498, 370/521, 370/529, 370/537, 370/505, 370/506, 725/32, 725/34, 725/35, 725/36, 725 87- 92, 725101-102, 725/151, 348/384, 348/423
• US Class Current: 370/505
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 2007/045 Fill bit or bits, idle words
• CPC Class Codes: H04N 21/2221 being a cable television head-end CATV in broadcast systems H04H20/78
• CPC Class Codes: H04N 21/235 Processing of additional data, e.g. scrambling of additional data or processing content descriptors
• CPC Class Codes: H04N 21/23611 Insertion of stuffing data into a multiplex stream, e.g. to obtain a constant bitrate synchronisation arrangements in time-division multiplex systems using bit stuffing for systems with different or fluctuating information rates H04J3/073
• CPC Class Codes: H04N 21/435 Processing of additional data, e.g. decrypting of additional data, reconstructing software from modules extracted from the transport stream
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 7/17309 Transmission or handling of upstream communications

Abstract

Apparatus and methods for transparently using otherwise wasted bandwidth associated with variable-rate program streams to deliver additional content. In one embodiment, the network comprises a broadcast switched architecture (BSA), and the program streams are loaded up to a target rate using “null” packets and then delivered over the network infrastructure to a plurality of hub sites. The streams are then unloaded to reproduce the original variable streams, and the bandwidth vacated by removal of the null packets used as the transport mechanism for additional (e.g., non time-sensitive) content to be delivered to the subscribers. The process can also be substantially automated and anticipatory (through, e.g., transmission of null bit insertion data downstream). The invention can also advantageously be implemented with minimal modifications to existing infrastructure, and supports business and operational supervisory processes. Network server, QAM modulator, and CPE apparatus implementing the aforementioned methodologies are also disclosed.

Claims

1. Modulator apparatus configured for use in a broadcast switched digital network, said network having a distribution network in communication therewith and being configured to carry a plurality of program streams, said apparatus comprising:

a processor;

a storage device in data communication with said processor;

a network interface configured to receive a plurality of variable rate program streams from said distribution network; and

a computer program operative to run on said modulator apparatus, said computer program being configured to;

receive said plurality of variable rate program streams;

insert secondary content along with said obtained variable rate streams, said insertion comprising either;

insertion of at least time-sensitive secondary content, it is determined that a temporal requirement associated therewith can be accommodated; and

insertion of non-time sensitive secondary content comprising at least one of an application program file, an image data file, or an audio data file if the temporal requirement cannot be met; and

transmit said variable bit rate streams and said secondary content to a plurality of client devices downstream of said modulator apparatus;

wherein an amount of secondary content for insertion is based at least in part on a calculation of a difference between rates of said variable rate program streams and a maximum rate for said network.

2. The modulator apparatus of claim 1, wherein said transmission of said variable rate streams is performed using quadrature amplitude modulation (QAM).

3. The modulator apparatus of claim 1, wherein said loaded program streams comprise a plurality of content packets and at least one null packet, and said computer program is configured to identify said null data based on a packet header of said at least one null packet.

4. The modulator apparatus of claim 1, wherein said received plurality of variable rate program streams comprise null packets.

5. The modulator apparatus of claim 4, wherein said computer program is configured to insert said secondary content by:

determination of an amount of said null packets in at least one of said variable rate program streams;

removal said null packets from said at least one variable rate program stream; and

insertion said secondary content in place of said at least portion of said null packets into said at least one stream.

6. The modulator apparatus of claim 1, wherein said insertion of said secondary content is such that said transmission of said variable bit rate streams and said secondary content comprises transmission of a substantially constant data rate program stream composed thereof.

7. The modulator apparatus of claim 1, wherein said secondary content comprises non-time sensitive data selected from the group consisting of:

(i) application program files;

(ii) image data files, or (iii) audio data files.

8. The modulator apparatus of claim 1, wherein said secondary content comprises time-sensitive data, and said processing apparatus is configured to determine in advance of said insertion of said time-sensitive data whether a temporal requirement associated with said time-sensitive data can be accommodated.

9. The modulator apparatus of claim 1, wherein said transmission of said variable bit rate streams and said secondary content to a plurality of client devices downstream of said modulator apparatus is performed via said distribution network.

10. Modulator apparatus for use in a content delivery network configured to provide a plurality of program streams to a plurality of client devices, said apparatus comprising:

a processor;

a storage device in data communication with said processor;

a network interface configured to receive a plurality program streams from a distribution network of said content delivery network, said program streams comprising streams having null data and variable rates; and

a computer program operative to run on said processor, said computer program configured to;

substitute secondary data for at least a portion of said null data within said program streams, an amount of said secondary data substituted being based at least in part on a difference between said variable rates and a maximum rate for said network;

said substitution comprising;

substitution of at least time-sensitive secondary data if it is determined that a temporal requirement associated with said time-sensitive secondary data can be accommodated;

or

substitution of non-time sensitive secondary data files if the at least one temporal requirement cannot be met;

and transmit said variable bit rate streams and said secondary data to said plurality of client devices.

11. The modulator apparatus of claim 10, wherein said content delivery network comprises a broadcast switched digital network.

12. The modulator apparatus of claim 10, wherein said secondary data comprises locally generated content.

13. The modulator apparatus of claim 10, wherein the variable rate bit streams and secondary content together comprise a substantially constant bit rate for transmission.

14. A method for transmission of content to a plurality of client devices in a content distribution network, said method comprising:

receiving at a modulator apparatus a plurality of variable rate program streams;

inserting secondary content along with said variable rate streams, an amount of secondary content for insertion based at least in part on a calculation of a difference between rates of said variable rate program streams and a maximum rate for said network, said act of inserting comprising;

determining whether a temporal requirement associated with time sensitive secondary content can be met and if so, inserting said time sensitive content; and

if said temporal requirement cannot be met, inserting non-time sensitive secondary content; and

transmitting substantially constant bit rate streams from said modulator apparatus to said plurality of client devices, said substantially constant bit rate streams comprising respective ones of said variable bit rate streams and at least a portion of said secondary content.

15. The method of claim 14, wherein said method wherein said network comprises a broadcast switched digital network having a distribution network in communication therewith.

16. The method of claim 14, wherein said transmitting of said constant rate streams is performed using quadrature amplitude modulation (QAM).

17. The method of claim 14, wherein said secondary content comprises content generated for consumption by ones of said client devices disposed in a prescribed geographic area.

18. The method of claim 14, wherein said receiving a plurality of variable rate program streams comprises receiving a plurality of constant rate streams comprised of said variable rate program streams and null data.

19. The method of claim 18, wherein said inserting of said secondary content comprises removal of said null data and replacement with said secondary content.

20. A method for delivery of content to one or more client devices in a network, said method comprising:

receiving at a modulator apparatus a plurality of constant rate program streams, each of said constant rate streams comprising at least one variable rate stream and a plurality of null packets;

said modulator apparatus removing said plurality of null packets from said at least one variable rate stream;

said modulator apparatus adding secondary data to said at least one variable rate stream;

an amount of secondary data added based at least in part on a calculation of a difference between rates of said at least one variable rate program stream and a maximum rate for said network; and

delivering at least one substantially constant bit rate stream from said modulator apparatus to said one or more client devices, said at least one substantially constant bit rate stream comprising said at least one variable bit rate stream and said secondary data;

wherein said secondary data comprises at least one of (i) time sensitive data, said time sensitive data having at least one temporal requirement associated therewith, and (ii) non-time sensitive application program file data, image file data, or audio file data; and

wherein said method further comprises evaluating whether said at least one temporal requirement can be met before adding said time-sensitive data, if said at least one temporal requirement cannot be met, adding said non-time sensitive data.

21. The method of claim 20, wherein said method occurs substantially at a local node of a content delivery network, and said secondary data comprises content generated for consumption by client devices within an area local to said local node.

22. The method of claim 21, wherein said act of removing said plurality of null packets comprises identifying a packet header of each of said null packets.

23. The method of claim 20, further comprising evaluating whether said at least one temporal requirement can be met before adding said time-sensitive data.

24. A non-transitory computer readable medium for use in a digital distribution network, said network being configured to carry a plurality of program streams, said computer readable medium comprising a plurality of instructions which when executed:

receive variable rate data having stuffing data associated therewith, said variable rate data and said stuffing data forming a substantially constant rate stream;

remove at least a portion of said stuffing data from said substantially constant rate stream;

identify secondary data for combination with said variable rate data;

calculate a difference between a rate of said variable rate data and a limitation rate associated with said network;

combine said secondary data with said variable rate data based at least in part on said calculated difference to create a second substantially constant rate stream; and

deliver said second substantially constant rate stream one or more client devices in said network;

wherein said secondary data comprises at least one of non-time sensitive data and time sensitive data, said non-time sensitive data comprising at least one of application program file data, image file data file, and audio file data; and

wherein if said second content comprises time sensitive data, said identification of secondary data further comprising determining whether a time-related requirement associated with said time sensitive data can be supported, if said time-related requirement cannot be supported insert said non-time sensitive data.

25. The non-transitory computer readable medium of claim 24, wherein said second content comprises non-time sensitive data selected from the group consisting of:

(i) application program files;

(ii) image data files, or (iii) audio data files.

26. The non-transitory computer readable medium of claim 25, wherein said secondary content comprises time-sensitive data, and said plurality of instructions are further configured to determine in advance Of said insertion of said time-sensitive data whether a quality of service (QoS) related requirement associated with said time-sensitive data can be accommodated.

27. Modulator apparatus for use in a digital content distribution network configured to carry a plurality of program streams, said apparatus comprising:

processor means;

a storage device in data communication with said processor means;

means for interfacing with said distribution network; and

logic means in communication with said means for interfacing and said processor and operative to;

receive said plurality of variable rate program streams;

calculate of a difference between rates of said variable rate program streams and a maximum rate for said distribution network;

insert secondary content along with said obtained variable rate streams to form combined streams, said insertion of secondary content being based at least in part on said calculation, and said insertion comprising;

insertion of at least time-sensitive data id at least one temporal requirement associated therewith may be accommodated; and

insertion of non-time sensitive data files if said at least one temporal requirement cannot be accommodated, said non-time sensitive files including at least one of application program file data, image file data, and audio file data; and

transmit said combined streams to a plurality of client devices downstream of said modulator apparatus.

28. The modulator apparatus of claim 27, wherein said secondary content comprises non-time sensitive data selected from the group consisting of:

(i) application program files;

(ii) image data files, or (iii) audio data files.

29. The modulator apparatus of claim 27, wherein said secondary content comprises time-sensitive data, and said processing apparatus is configured to determine in advance of said insertion of said time-sensitive data whether a quality of service (QoS) related requirement associated with said time-sensitive data can be accommodated.

30. Modulator apparatus for use in a content delivery network, said apparatus configured to provide a plurality of program streams to a plurality of client devices, said apparatus comprising:

a processor;

a storage device in data communication with said processor;

a network interface configured to receive a plurality program streams from a distribution network of said content delivery network, said program streams comprising streams having variable rates; and

a computer program operative to run on said processor, said computer program being configured to insert secondary data within at least one of said program streams, an amount of said secondary data inserted being based at least in part on a difference between at least one of said variable rates and a maximum rate associated with said network, said computer program comprising;

first logic configured to insert time-sensitive secondary data if it is determined that a temporal requirement associated with said time-sensitive secondary data can be met; and

second logic for inserting non-time sensitive secondary data files at least when said temporal requirement cannot be met.