Downstream channel change technique implemented in an access network

• US 7,656,890 B2
• Filed: 07/10/2006
• Issued: 02/02/2010
• Est. Priority Date: 10/13/1999
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Lu, Yong, Zang, Joanna Qun, Chapman, John T., Daruwalla, Feisal Y., Crocker, Daniel W.
• Primary Examiner(s): Harper; Kevin C
• Application Number:
  US11/484,288
• Publication Number:
  US 20060262722A1
• Time in Patent Office: 1,303 Days
• Field of Search: 370/431, 370/465, 370/468
• US Class Current: 370/431
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04N 21/242 Synchronization processes, e.g. processing of PCR [Program Clock References] arrangements for synchronising broadcast or distribution via plural systems in broadcast distribution systems H04H20/18

Abstract

A dynamic channel change technique is disclosed which may be implemented between nodes and a Head End of an access network. Initially a network device may communicate with the Head End via a first downstream channel and a first upstream channel. When the network device receives a dynamic channel change request which includes instructions for the network device to switch to a second downstream channel, the network device may respond by switching from the first downstream channel to the second downstream channel. Thereafter, the network device may communicate with the Head End via the second downstream channel and first upstream channel. Further, according to a specific embodiment, the dynamic channel change request may also include an upstream channel change request for causing the network device to switch from a first upstream channel to a second upstream channel.

Claims

1. A method for facilitating communications between a network node and a Head End of an access network, the access network including a plurality of nodes which communicate with the Head End via at least one upstream channel and at least one downstream channel, the at least one downstream channel including a first downstream channel and a second downstream channel, the method comprising:

communicating between the Head End and a first network node of the plurality of nodes via the first downstream channel;

communicating between the Head End and a second network node of the plurality of nodes via the first downstream channel;

receiving, on a first upstream channel, a bandwidth allocation request from the first network node;

analyzing traffic loads on at least a portion of the at least one upstream and downstream channels, wherein said analyzing includes analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first network node;

generating, in response to the analysis of traffic loads, a first communication message, the first communication message including a request to perform a dynamic channel change (DCC) operation, said dynamic channel change request including downstream channel identifier information associated with the second downstream channel, said dynamic channel change request further including instructions for causing the first network node to perform a downstream channel change operation to thereby cause the first network node to receive downstream communications via the second downstream channel;

communicating between the Head End and the first network node via the second downstream channel after successful completion of the downstream channel change operation at the first network node; and

communicating between the Head End and the second network node via the first downstream channel after successful completion of the downstream channel change operation at the first network node.

2. The method of claim 1 wherein the method is implemented at a cable modem termination system (CMTS) of the access network.

3. The method of claim 1 further comprising:

identifying a selected upstream channel suitable for use in accommodating the bandwidth allocation request from the first network node; and

transmitting to the first network node an upstream channel change request which includes instructions for causing the first network node to transmit upstream data via said selected upstream channel.

4. The method of claim 1 wherein said access network is a wireless network.

5. The method of claim 1 wherein said access network is a cable network, said plurality of nodes are cable modems, and wherein said Head End comprises a Cable Modem Termination System (CMTS).

6. A method for facilitating communications between a network node and a Head End of an access network, the access network including a plurality of nodes which communicate with the Head End via at least one upstream channel and at least one downstream channel, the at least one downstream channel including a first downstream channel and a second downstream channel, the method comprising:

communicating between the Head End and a first network node of the plurality of nodes via the first downstream channel;

communicating between the Head End and a second network node of the plurality of nodes via the first downstream channel;

analyzing traffic loads on at least a portion of the at least one upstream and downstream channels, wherein said analyzing includes analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first network node;

generating, in response to the analysis of traffic loads, a first communication message, the first communication message including a request to perform a dynamic channel change (DCC) operation, said dynamic channel change request including downstream channel identifier information associated with the second downstream channel, said dynamic channel change request further including instructions for causing the first network node to perform a downstream channel change operation to thereby cause the first network node to receive downstream communications via the second downstream channel;

allocating at least one bandwidth resource assignment on the second downstream channel for use in communicating with the first network node;

communicating between the Head End and the first network node via the second downstream channel after successful completion of the downstream channel change operation at the first network node; and

communicating between the Head End and the second network node via the first downstream channel after successful completion of the downstream channel change operation at the first network node.

7. The method of claim 6 further comprising:

detecting that the first network node is successfully receiving transmissions on the second downstream channel; and

de-allocating at least one bandwidth resource assignment associated with the first network node on the first downstream channel.

8. The method of claim 6 further comprising:

receiving a dynamic channel change response from the first network node, wherein said dynamic channel change response has been generated in response to the first network node receiving the dynamic channel change request.

9. The method of claim 6 further comprising:

de-allocating the at least one bandwidth resource assignment in response to not receiving a dynamic channel change response from the first network node after a first time period has elapsed.

10. The method of claim 9 further comprising:

re-transmitting the dynamic channel change request to the first network node in response to not receiving a dynamic channel change response from the first network node after a second time period has elapsed.

11. The method of claim 8 further comprising:

de-allocating the at least one bandwidth resource assignment in response to detecting that the first network node is not successfully receiving transmissions on the second downstream channel.

12. The method of claim 6 wherein the method is implemented at a cable modem termination system (CMTS) of the access network.

13. The method of claim 6 wherein said access network is a wireless network.

14. The method of claim 6 wherein said access network is a cable network, said plurality of nodes are cable modems, and wherein said Head End comprises a Cable Modem Termination System (CMTS).

15. A system for facilitating communications between a network node and a Head End of an access network, the access network including a plurality of nodes which communicate with the Head End via at least one upstream channel and at least one downstream channel, the at least one downstream channel including a first downstream channel and a second downstream channel, the system comprising:

at least one processor;

at least one interface; and

memory;

the system being operable to;

communicate between the Head End and a first network node of the plurality of nodes via the first downstream channel;

communicate between the Head End and a second network node of the plurality of nodes via the first downstream channel;

receive, on a first upstream channel, a bandwidth allocation request from the first network node;

analyze traffic loads on at least a portion of the at least one upstream and downstream channels, wherein said analyzing includes analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first network node;

generate, in response to the analysis of traffic loads, a first communication message, the first communication message including a request to perform a dynamic channel change (DCC) operation, said dynamic channel change request including downstream channel identifier information associated with the second downstream channel, said dynamic channel change request further including instructions for causing the first network node to perform a downstream channel change operation to thereby cause the first network node to receive downstream communications via the second downstream channel;

communicate between the Head End and the first network node via the second downstream channel after successful completion of the downstream channel change operation at the first network node; and

communicate between the Head End and the second network node via the first downstream channel after successful completion of the downstream channel change operation at the first network node.

16. The system of claim 15 wherein the system is implemented at a cable modem termination system (CMTS) of the access network.

17. The system of claim 15 being further operable to:

identify a selected upstream channel suitable for use in accommodating the bandwidth allocation request from the first network node; and

transmit to the first network node an upstream channel change request which includes instructions for causing the first network node to transmit upstream data via said selected upstream channel.

18. The system of claim 15 wherein said access network is a wireless network.

19. The system of claim 15 wherein said access network is a cable network, said plurality of nodes are cable modems, and wherein said Head End comprises a Cable Modem Termination System (CMTS).

20. A system for facilitating communications between a network node and a Head End of an access network, the access network including a plurality of nodes which communicate with the Head End via at least one upstream channel and at least one downstream channel, the at least one downstream channel including a first downstream channel and a second downstream channel, the system comprising:

at least one processor;

at least one interface; and

memory;

the system being operable to;

communicate between the Head End and a first network node of the plurality of nodes via the first downstream channel;

communicate between the Head End and a second network node of the plurality of nodes via the first downstream channel;

analyze traffic loads on at least a portion of the at least one upstream and downstream channels, wherein said analyzing includes analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first network node;

generate, in response to the analysis of traffic loads, a first communication message, the first communication message including a request to perform a dynamic channel change (DCC) operation, said dynamic channel change request including downstream channel identifier information associated with the second downstream channel, said dynamic channel change request further including instructions for causing the first network node to perform a downstream channel change operation to thereby cause the first network node to receive downstream communications via the second downstream channel;

allocate at least one bandwidth resource assignment on the second downstream channel for use in communicating with the first network node;

communicate between the Head End and the first network node via the second downstream channel after successful completion of the downstream channel change operation at the first network node; and

communicate between the Head End and the second network node via the first downstream channel after successful completion of the downstream channel change operation at the first network node.

21. The system of claim 20 being further operable to:

detect that the first network node is successfully receiving transmissions on the second downstream channel; and

de-allocate at least one bandwidth resource assignment associated with the first network node on the first downstream channel.

22. The system of claim 20 being further operable to:

receive a dynamic channel change response from the first network node, wherein said dynamic channel change response has been generated in response to the first network node receiving the dynamic channel change request.

23. The system of claim 20 being further operable to:

de-allocate the at least one bandwidth resource assignment in response to not receiving a dynamic channel change response from the first network node after a first time period has elapsed.

24. The system of claim 23 being further operable to:

re-transmit the dynamic channel change request to the first network node in response to not receiving a dynamic channel change response from the first network node after a second time period has elapsed.

25. The system of claim 22 being further operable to:

de-allocate the at least one bandwidth resource assignment in response to detect that the first network node is not successfully receiving transmissions on the second downstream channel.

26. The system of claim 20 wherein the system is implemented at a cable modem termination system (CMTS) of the access network.

27. The system of claim 20 wherein said access network is a wireless network.

28. The system of claim 20 wherein said access network is a cable network, said plurality of nodes are cable modems, and wherein said Head End comprises a Cable Modem Termination System (CMTS).

29. A system for facilitating communications between a network node and a Head End of an access network, the access network including a plurality of nodes which communicate with the Head End via at least one upstream channel and at least one downstream channel, the at least one downstream channel including a first downstream channel and a second downstream channel, the system comprising:

at least one processor;

memory;

means for communicating between the Head End and a first network node of the plurality of nodes via the first downstream channel;

means for communicating between the Head End and a second network node of the plurality of nodes via the first downstream channel;

means for receiving, on a first upstream channel, a bandwidth allocation request from the first network node;

means for analyzing traffic loads on at least a portion of the at least one upstream and downstream channels, wherein said analyzing includes analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first network node;

means for generating, in response to the analysis of traffic loads, a first communication message, the first communication message including a request to perform a dynamic channel change (DCC) operation, said dynamic channel change request including downstream channel identifier information associated with the second downstream channel, said dynamic channel change request further including instructions for causing the first network node to perform a downstream channel change operation to thereby cause the first network node to receive downstream communications via the second downstream channel;

means for communicating between the Head End and the first network node via the second downstream channel after successful completion of the downstream channel change operation at the first network node; and

means for communicating between the Head End and the second network node via the first downstream channel after successful completion of the downstream channel change operation at the first network node.

30. A system for facilitating communications between a network node and a Head End of an access network, the access network including a plurality of nodes which communicate with the Head End via at least one upstream channel and at least one downstream channel, the at least one downstream channel including a first downstream channel and a second downstream channel, the system comprising:

at least one processor;

memory;

means for communicating between the Head End and a first network node of the plurality of nodes via the first downstream channel;

means for communicating between the Head End and a second network node of the plurality of nodes via the first downstream channel;

means for analyzing traffic loads on at least a portion of the at least one upstream and downstream channels, wherein said analyzing includes analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first network node;

means for generating, in response to the analysis of traffic loads, a first communication message, the first communication message including a request to perform a dynamic channel change (DCC) operation, said dynamic channel change request including downstream channel identifier information associated with the second downstream channel, said dynamic channel change request further including instructions for causing the first network node to perform a downstream channel change operation to thereby cause the first network node to receive downstream communications via the second downstream channel;

means for allocating at least one bandwidth resource assignment on the second downstream channel for use in communicating with the first network node;

means for communicating between the Head End and the first network node via the second downstream channel after successful completion of the downstream channel change operation at the first network node; and

means for communicating between the Head End and the second network node via the first downstream channel after successful completion of the downstream channel change operation at the first network node.