Methods and apparatus for variable delay compensation in networks

• US 20050177855A1
• Filed: 02/11/2005
• Published: 08/11/2005
• Est. Priority Date: 02/11/2005
• Status: Active Grant

• Current Assignee: Time Warner Cable Enterprises LLC (Charter Communications Incorporated)
• Original Assignee: Time Warner Cable Inc. (Charter Communications Incorporated)
• Inventors: Maynard, Stephen L., Callahan, John, Autruong, Tho, Nielsen, Nicholas
• Granted Patent: US 7,954,128 B2
• Time in Patent Office: Days
• US Class Current: 725/88
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04N 21/2387 Stream processing in response to a playback request from an end-user, e.g. for trick-play
• CPC Class Codes: H04N 21/2402 Monitoring of the downstream path of the transmission network, e.g. bandwidth available traffic monitoring in data switching networks H04L43/00; monitoring data switching networks utilization H04L43/0876
• CPC Class Codes: H04N 21/47202 for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/47217 for controlling playback functions for recorded or on-demand content, e.g. using progress bars, mode or play-point indicators or bookmarks specific graphical features in visual interfaces H04N21/4312
• CPC Class Codes: H04N 21/64738 Monitoring network characteristics, e.g. bandwidth, congestion level data switched network analysis H04L41/14; monitoring functioning in data switched networks H04L43/0817; flow control in packet networks H04L47/10
• CPC Class Codes: H04N 21/6587 Control parameters, e.g. trick play commands, viewpoint selection
• CPC Class Codes: H04N 7/17336 Handling of requests in head-ends

Abstract

Methods and apparatus for performing dynamic compensation for delays over extant infrastructure within a content-based network. In one embodiment, the network comprises a cable network, and the infrastructure comprises that nominally used for on-demand (OD) services such as VOD. The method includes periodically or situationally assessing variable delays within the system associated with functional commands (such as “trick mode” commands), and dynamically compensating for these variable delays in order to improve the accuracy and timeliness of the user'"'"'s trick mode command. This approach increases user satisfaction, and obviates the issuance of additional compensatory trick mode commands that only further degrade the performance of the network.

Claims

1. A method of providing trick mode functionality during a video on-demand (VOD) session within a cable network, comprising:

receiving a trick mode command from a user via consumer premises equipment (CPE) operatively coupled to said network;

dynamically generating a current compensation value for said trick mode command, said current compensation value being generated based at least in part as a moving average of a prior iteration of said current compensation value and a new compensation value, said new compensation value being derived from a fraction of a round-trip delay value measured within at least a portion of said network, said current compensation value also being adjusted for a hysteresis value;

adjusting said current compensation value for a scale factor of said trick mode command to produce an adjusted current compensation value; and

applying said adjusted current compensation value to data being provided to said user via said CPE.

12. The method of claim 11, wherein said act of generating a moving function comprises generating a moving average comprising said first value and a plurality of previous iterations of said second value.

13. The method of claim 12, wherein at least a portion of said plurality of previous iterations are not equally weighted within said average calculation.

2. A method of operating CPE within a cable network, comprising:

obtaining a plurality of parameters;

determining a first delay compensation value;

generating a window function; and

generating a second compensation value based at least in part on said first value and said window function.

3. The method of claim 2, wherein each of said plurality of parameters is constant.

4. The method of claim 2, wherein at least a portion of said plurality of parameters is configurable by a system operator.

5. The method of claim 4, wherein said plurality of parameters comprise a user response time, and a parameter used in said act of generating a window function.

6. The method of claim 5, wherein said plurality of parameters comprise a rate compensation value.

7. The method of claim 5, wherein said act of determining a delay compensation value comprises:

taking a difference between timestamp values at first and second points within said network; and

determining a one-way delay value for at least a portion of the network from said difference.

8. The method of claim 7, wherein said act of determining a delay compensation value further comprises adding said user response time to said one-way delay value.

9. The method of claim 5, wherein said act of generating a window function comprises using said parameter to specify said window such that said first compensation value must fall outside of said window in order to be included within a moving average calculated based on said first compensation value and a prior iteration of said second value.

10. The method of claim 2, wherein said method is performed iteratively, and said act of generating a second compensation value comprises adding said first value and a previous iteration of said second value to produce a result, and dividing the result by an integer.

11. The method of claim 2, wherein said act of generating a second compensation value comprises generating a moving function comprising at least said first value and a previous iteration of said second value.

14. The method of claim 2, wherein said operating comprises operating to provide trick mode functionality to a user of said network, said method further comprising applying an adjustment for the scale of a trick mode command.

15. The method of claim 2, further comprising generating a protocol command comprising an adjusted play time value, said adjusted play time value being adjusted based at least in part on said second compensation value.

16. A method of providing trick mode functionality within a cable network, comprising:

receiving a trick mode command from a user via a device operatively coupled to said network;

dynamically generating a current compensation value for said trick mode command; and

applying said compensation value to affect the delivery of data being provided to said user via said device.

17. The method of claim 16, wherein said act of dynamically generating comprises the following steps performed in substantially iterative fashion;

determining a new delay compensation value based at least on a plurality of parameters;

generating a hysteresis function; and

generating said current compensation value based at least in part on said new value and said hysteresis function.

18. The method of claim 16, further comprising applying a scale-based adjustment to said current compensation value.

19. The method of claim 17, wherein said trick mode command is selected from the group consisting of:

(i) fast-forward commands;

(ii) rewind commands; and

(iii) skip-to commands.

20. The method of claim 16, wherein said device comprises a set-top box.

21. The method of claim 16, wherein said acts of dynamically generating and applying cooperate to reduce the susceptibility of said trick mode functionality to variable delays within said network.

22. Cable network consumer premises equipment (CPE) adapted to provide trick mode functionality, comprising:

a processor;

a storage device operatively coupled to the processor;

a first computer program at least partly stored on said storage device and adapted to provide a user interface whereby said user can enter trick mode commands; and

a second computer program at least partly stored on said storage device and adapted to dynamically generate a current compensation value for said trick mode command based at least in part on;

(i) a plurality of configuration values provided by a node of said network; and

(ii) dynamically determined values relating at least in part to delays within said network.

23. The CPE of claim 22, wherein said first and second computer programs comprise a single computer program.

24. The CPE of claim 22, wherein said first computer program comprises an application program, and said second program comprises software disposed at a layer below the application layer in a protocol stack of said CPE.

25. The CPE of claim 22, wherein said dynamic generation of a current compensation value comprises:

determining a new delay compensation value based at least said plurality of configuration values;

providing a hysteresis parameter; and

generating said current compensation value based at least in part on said new value and said hysteresis parameter.

26. The CPE of claim 25, wherein said act of generating said current compensation value based at least in part on said new value and said hysteresis parameter comprises forming a moving average, said average based at least in part on said new compensation value.

27. The CPE of claim 25, wherein said plurality of configuration values comprise said hysteresis parameter.

28. The CPE of claim 22, wherein said plurality of configuration values are provided to said CPE via an in-band channel.

29. A network device adapted to perform dynamic compensation for trick mode commands received from consumer premises equipment (CPE), comprising:

a processor;

a storage device in data communication with said processor; and

a computer program at least partly stored on said storage device and adapted to dynamically generate a current compensation value for a trick mode command based at least in part on;

(i) a plurality of configuration values; and

(ii) dynamically determined values relating at least in part to delays within said network.

30. The network device of claim 29, wherein said dynamic generation of a current compensation value comprises:

determining a new delay compensation value based at least said plurality of configuration values;

providing a hysteresis parameter; and

generating said current compensation value based at least in part on said new value and said hysteresis parameter.

31. The network device of claim 30, wherein said generation of said current compensation value based at least in part on said new value and said hysteresis parameter comprises forming a moving average, said average based at least in part on said new compensation value.

32. The network device of claim 30, wherein said plurality of configuration values comprise said hysteresis parameter.

33. The network device of claim 29, wherein said plurality of configuration values are provided to said network device via an out-of-band channel.