Configurable hybrid medium access control for cable metropolitan area networks

• US 5,572,517 A
• Filed: 03/10/1995
• Issued: 11/05/1996
• Est. Priority Date: 02/28/1995
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: General Instrument Corporation (CommScope Holding Company, Inc.)
• Inventors: Safadi, Reem
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): BLUM, RUSSELL
• Application Number:
  US08/402,007
• Time in Patent Office: 606 Days
• Field of Search: 370/24, 370/30, 370/50, 370/71, 370/73, 370/124, 370/82, 370/83, 370/79, 370/85.1, 370/85.2, 370/85.7, 370/85.8, 370/85.9, 370/95.1, 370/95.2, 370/95.3, 375/257, 455/3.1, 455/5.1, 340/825.08, 348/6, 348/10, 348/12, 348/13, 348/17, 348/14
• US Class Current: 370/431
• CPC Class Codes: H04J 3/1694 Allocation of channels in TDM/TDMA networks, e.g. distributed multiplexers Passive Optical Networks H04Q11/0062
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 2012/5605 Fibre
• CPC Class Codes: H04L 2012/5606 Metallic
• CPC Class Codes: H04L 2012/561 Star, e.g. cross-connect, concentrator, subscriber group equipment, remote electronics
• CPC Class Codes: H04L 2012/5642 Multicast/broadcast/point-multipoint, e.g. VOD
• CPC Class Codes: H04L 2012/5667 IP over ATM
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04N 21/2221 being a cable television head-end CATV in broadcast systems H04H20/78
• CPC Class Codes: H04N 21/2381 Adapting the multiplex stream to a specific network, e.g. an Internet Protocol [IP] network transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/2665 Gathering content from different sources, e.g. Internet and satellite
• CPC Class Codes: H04N 21/4381 Recovering the multiplex stream from a specific network, e.g. recovering MPEG packets from ATM cells transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6168 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/64307 ATM
• CPC Class Codes: H04N 7/17309 Transmission or handling of upstream communications
• CPC Class Codes: H04N 7/22 Adaptations for optical transmission
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

The hybrid medium access control MAC system is configurable to the type of communication required to support a desired application or service. The MAC system analyzes services requested from a settop terminal, or a network controller client, and determines the best MAC component for transmitting signals upstream based on the resources required by the service and the available network resources. A portion of the upstream channel spectrum is allocated to each of the MAC components: 1) POP; 2) assigned static TDMA; 3) assigned dynamic multi-rate TDMA; and 4) random slot reservation--dynamic slot allocation TDMA. Depending upon the communication requirements of the service desired, the configurable MAC system will select the MAC component best suited to support the service. A frequency agile transmitter is then tuned to the channel which has been preallocated for the selected MAC component(s). As communication traffic varies over time, the system reallocates portions of the upstream channel spectrum among the different MAC components and may also reconfigure a specific MAC component.

Claims

1. A system for controlling access to a bi-directional cable television hybrid fiber-coax network having a plurality of upstream and downstream communication channels, each upstream channel supporting a different communication mode, the system comprising a headend unit and at least one subscriber unit:

said subscriber unit having;

means for receiving a request for transmitting over said network;

means for determining the type of communication to be transmitted;

means for selecting a communication mode, based upon said determination, for transmitting said communication;

means for transmitting a connection request over one of said upstream channels;

means for receiving a connection acknowledgment over one of said downstream channels, wherein said acknowledgement includes an authorized communication channel assignment; and

means for transmitting communications over said authorized channel; and

said headend unit having;

means for receiving said connection request from said subscriber unit;

means for monitoring communication traffic over an upstream channel associated with said selected communication mode;

means for configuring selected parameters of said communication mode, said configuring means being responsive to said monitoring means; and

means for transmitting a connection acknowledgment over said downstream channel to said subscriber unit.

2. The system of claim 1 wherein said upstream channels are further divided into repeating frames, each frame having a plurality of time slots and said headend unit further includes means for notifying said subscriber unit when time slots are available for communicating.

3. The system of claim 2 wherein said communication modes include plain old polling;

assigned static TDMA;

assigned dynamic multi-rate TDMA; and

random slot reservation--dynamic slot allocation TDMA.

4. The system of claim 3 wherein said selected parameters include time slot size, frame size, number of time slots and spacing between time slots within said communication mode.

5. The system of claim 2 wherein each of said communication modes is supported by a plurality of upstreams channels, and said headend unit further includes means for dynamically allocating said channels among said communication modes.

6. The system of claim 5 wherein said allocating means is responsive to said monitoring means.

7. The system of claim 2 wherein said headend is responsive to connection requests from communicating entities located upstream of said headend.

8. A system for controlling access to a bi-directional information transport medium between at least one subscriber unit and a headend unit, the transport medium having a plurality of communication channels, each channel supporting a different communication mode, the system comprising:

said subscriber unit having;

means for receiving a request for transmitting over said transport medium;

means for determining the type of communication to be transmitted;

means for selecting a communication mode, based upon said determination, for transmitting said communication;

means for transmitting communications over a selected channel associated with said communication mode; and

means for receiving communications over a second channel; and

said headend unit having;

means for receiving said communications over said selected channel from said subscriber unit;

means for monitoring communication traffic over said channel;

means for configuring selected parameters of said communicating mode, said configuring means being responsive to said monitoring means; and

means for transmitting communications to said subscriber unit over said second channel.

11. The system of claim 8 wherein said selected parameters include time slot size, frame size, number of time slots and spacing between time slots.

13. The system of claim 8 further including a plurality of subscriber units, wherein said subscriber units are divided into spatially diverse groups.

14. The system of claim 8 wherein said subscriber unit further includes means for tuning a transmitter for transmitting over said selected communication channel, and means for tuning a receiver for receiving over said second channel.

18. The system of claim 8 wherein said medium comprises a hybrid fiber-coaxial transmission system.

20. The system of claim 8 wherein said medium comprises a coaxial transmission system.

9. A system for controlling access to a bi-directional information transport medium between at least one subscriber unit and a headend unit, the transport medium having a plurality of communication channels, each channel supporting a different communication mode, the system comprising:

said subscriber unit having;

means for receiving a request for transmitting over said transport medium;

means for determining the type of communication to be transmitted;

means for selecting a communication mode, based upon said determination, for transmitting said communication, wherein said communication modes include plain old polling;

assigned static TDMA;

assigned dynamic multi-rate TDMA; and

random slot reservation-dynamic slot allocation TDMA;

means for transmitting communications over a selected channel associated with said communication mode; and

means for receiving communications over a second channel; and

said headend unit having;

means for receiving said communications over said selected channel from said subscriber unit;

means for monitoring communication traffic over said channel;

means for configuring selected parameters of said communicating mode, said configuring means being responsive to said monitoring means; and

means for transmitting communications to said subscriber unit over said second channel.

10. The system of claim 9 wherein said selected parameters include time slot size, frame size, number of time slots and spacing between time slots within said dynamic multi-rate TDMA communication mode.

12. The system of claim 9 wherein said headend further includes means for notifying said subscriber unit when a time slot within a channel has been released.

15. The system of claim 9 wherein each of said communication modes is supported by a plurality of channels, and said headend unit further includes means for dynamically allocating said channels among said communication modes.

16. The system of claim 15 wherein said allocating means is responsive to said monitoring means.

17. The system of claim 9 wherein said headend is responsive to connection requests from communicating entities located upstream of said headend.

19. The system of claim 9 wherein said medium comprises a fiber optic transmission system.

21. A subscriber unit for controlling access to a bi-directional information transport medium, the transport medium having a plurality of communication channels, each channel supporting a different communication mode, said subscriber unit comprising:

means for receiving a request for transmitting over said transport medium;

means for determining the type of communication to be transmitted;

means for selecting a communication mode, based upon said determination, for transmitting said communication;

means for transmitting communications over a selected channel associated with said communication mode; and

means for receiving communications over a second channel.

22. A headend unit for controlling access to a bi-directional information transport medium by a plurality of subscriber units, the transport medium having a plurality of communication channels, each channel supporting a different communication mode, said headend unit comprising:

means for receiving connection requests over one of said channels from a plurality of subscriber units;

means for monitoring communication traffic over said channels;

means for allocating said plurality of channels among said communication modes, said allocating means being responsive to said monitoring means;

means for configuring selected parameters of said communication modes, said configuring means being responsive to said monitoring means; and

means for transmitting connection authorizations to said subscriber units over a second channel.

23. A method for controlling access to an information transport medium, the transport medium having a plurality of communication channels, each channel supporting a different communication mode, the method comprising:

receiving a request for transmitting over said transport medium;

determining the type of communication to be transmitted;

selecting a communication mode, based upon said determination, for transmitting said communication;

transmitting a connection request for communicating over said selected communication mode;

receiving a connection acknowledgment, comprising an authorized communication channel; and

transmitting said communication over said authorized channel.

24. A system for controlling access to a bi-directional cable television hybrid fiber-coax network having a plurality of upstream and downstream communication channels, each upstream channel supporting a different communication mode, the system comprising a headend unit, at least one network element manager located upstream of said headend unit and at least one subscriber unit located downstream of said headend unit:

said network element manager having;

means for specifying connection parameters for transmitting a communication over said network, said connection parameters including a connection rate;

means for transmitting said connection parameters over one of said downstream channels;

means for receiving a connection acknowledgment over one of said upstream channels; and

means for transmitting communications over one of said downstream channels; and

said headend unit having;

means for receiving said connection parameters from said network element manager;

means for determining the communication mode based upon said connection parameters;

means for monitoring communication traffic load over a plurality of upstream channels;

means for configuring said mode, said configuring means being responsive to said monitoring means; and

means for transmitting a connection acknowledgment over said upstream channel to said network element manager.

25. The system of claim 24 wherein said configuring means includes means for determining medium access control (MAC) parameters including upstream channel frequency, frame size, time slot size and spacing between time slots.

26. The system of claim 24 wherein said subscriber unit includes:

means for receiving a connection request from the headend unit for transmitting over said network, said request including said selected communication mode and said connection parameters; and

means for transmitting communications in accordance with said MAC parameters; and

said headend unit further includes;

means for transmitting communications over one of said downstream channels to said subscriber unit; and

means for receiving communications over one of said upstream channels from said subscriber unit.

27. A method for controlling access to an information transport medium, the transport medium having a plurality of communication channels, each channel capable of supporting at least one communication mode, the method comprising:

receiving a request for transmitting over said transport medium;

determining the type of communication to be transmitted;

selecting a communication mode, based upon said determination, for transmitting said communication;

transmitting a connection request for communicating using said selected communication mode;

receiving a connection acknowledgment, comprising an authorized communication channel; and

transmitting said communication over said authorized channel.

28. The method of claim 27 wherein each communication mode is utilized on a plurality of channels.

29. A system for controlling access to a bi-directional information transport network between at least one subscriber unit and a headend unit, the transport medium having a plurality of communication channels, each channel supporting at least two communication modes, the system comprising:

said subscriber unit having;

means for receiving a request for transmitting over said transport network;

means for determining the type of communication to be transmitted based upon said request;

means for selecting a communication mode and an upstream channel, based upon said determination, for transmitting said communication, wherein said communication modes include plain old polling;

assigned static TDMA;

assigned dynamic multi-rate TDMA; and

random slot reservation-dynamic slot allocation TDMA;

means for transmitting communications over said selected upstream channel; and

means for receiving communications over a downstream channel; and

said headend unit having;

means for receiving said communications over said selected upstream channel from said subscriber unit;

means for monitoring communication traffic over a plurality of upstream channels;

means for configuring selected parameters of said communication mode, said configuring means being responsive to said monitoring means; and

means for transmitting communications to said subscriber unit over a downstream channel.

30. A system for controlling access to a bi-directional cable television hybrid fiber-coax network having a plurality of upstream and downstream communication channels, each upstream channel supporting a different communication mode, the system comprising a headend unit, at least one network element manager located upstream of said headend unit and at least one subscriber unit located downstream of said headend unit:

said network element manager having;

means for specifying a type of communication for transmitting over said network;

means for transmitting said communication type over one of said downstream channels;

means for receiving a connection acknowledgment over one of said upstream channels; and

said headend unit having;

means for receiving said communication type from said network element manager;

means for monitoring communication traffic load over an upstream channel associated with said communication type;

means for selecting a communication mode and for configuring associated parameters of said mode based upon said communication type, said configuring means being responsive to said monitoring means; and

means for transmitting a connection acknowledgment over an upstream channel to said network element manager.

31. The system of claim 30 wherein said communication type includes synchronous, asynchronous, isochronous and anisochronous communications.

32. The system of claim 30 wherein said subscriber unit includes:

means for receiving a connection request from the headend unit for transmitting over said network, said request including the communication mode and associated parameters;

means for transmitting communications in accordance with said parameters; and

said headend unit further includes;

means for transmitting said connection acknowledgment over a downstream channel to said subscriber unit; and

means for receiving communications from said subscriber unit.