Downstream channel change technique implemented in an access network

• US 20060262722A1
• Filed: 07/10/2006
• Published: 11/23/2006
• Est. Priority Date: 10/13/1999
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Lu, Yong, Chapman, John T., Daruwalla, Feisal Y., Crocker, Daniel W., Zang, Joanna Qun
• Granted Patent: US 7,656,890 B2
• Time in Patent Office: Days
• US Class Current: 370/229
• 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:

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

analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first node;

selecting a particular downstream channel for accommodating the bandwidth allocation request from the node;

transmitting to the node, via a first downstream channel, a dynamic channel change request.

2. The method of claim 1 wherein the dynamic channel change request includes a request for the node to receive downstream transmissions on said selected downstream channel.

3. The method of claim 1 wherein the method is implemented at the Head End of the access network.

4. The method of claim 1 wherein said selecting further comprises selecting a particular upstream channel for accommodating the bandwidth allocation request from the node;

and

wherein the method further comprises transmitting to the node, via the first downstream channel, an upstream channel change request for the node to transmit upstream data via said selected upstream channel.

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

6. 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).

7. 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:

transmitting to a network node, via a first downstream channel, a dynamic channel change request, said dynamic channel change request including a request for the node to receive downstream transmissions on a selected downstream channel; and

allocating at least one bandwidth resource assignment on the selected downstream channel for communicating with the network node.

8. The method of claim 7 further comprising:

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

de-allocating at least one bandwidth resource assignment relating to the node on the first downstream channel.

9. The method of claim 7 further comprising receiving a dynamic channel change response, wherein said dynamic channel change response is generated in response to the network node receiving the dynamic channel change request.

10. The method of claim 7 further comprising de-allocating the at least one bandwidth resource assignment in response to not receiving a dynamic channel change response from the network node after a first predetermined time period has elapsed.

11. The method of claim 10 further comprising re-transmitting the dynamic channel change request to the first node in response to not receiving a dynamic channel change response from the network node after a second predetermined time period has elapsed.

12. The method of claim 9 further comprising de-allocating the at least one bandwidth resource assignment in response to detecting that the network node is not successfully receiving transmissions on the selected downstream channel.

13. The method of claim 7 wherein the method is implemented at the Head End of the access network.

14. The method of claim 7 wherein said access network is a wireless network.

15. The method of claim 7 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).

16. A system for facilitating communications in an access network, the access network including a plurality of nodes, the system comprising:

a Head End in communication with at least a portion of the network nodes;

the Head End including a first interface operable to receive data from a first network node via at least one upstream channel;

the Head End including a second interface operable to transmit data to the first network node via at least one downstream channel;

the Head End being operable to receive, via a first upstream channel, a bandwidth allocation request from the first network node;

the Head End being further operable to analyze traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request;

the Head End being operable to select a particular downstream channel for accommodating the bandwidth allocation request from the first node;

the Head End being operable to transmit to the fist node, via a first downstream channel, a dynamic channel change request.

17. The system of claim 16 wherein the dynamic channel change request includes a request for the node to receive downstream transmissions on said selected downstream channel.

18. The system of claim 16 wherein the Head End is further operable to select a particular upstream channel for accommodating the bandwidth allocation request;

and

wherein the Head End is further operable to transmit to the first node, via the first downstream channel, an upstream channel change request for the first node to transmit upstream data via said selected upstream channel.

19. The system of claim 16 wherein said access network is a wireless network.

20. The system of claim 16 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).

21. A system for facilitating communications in an access network, the access network including a plurality of nodes, the system comprising:

a Head End in communication with at least a portion of the network nodes;

the Head End including a first interface operable to receive data from a first network node via at least one upstream channel;

the Head End including a second interface operable to transmit data to the first network node via at least one downstream channel;

the Head End being operable to transmit to a network node, via a first downstream channel, a dynamic channel change request, said dynamic channel change request including a request for the node to receive downstream transmissions on a selected downstream channel; and

wherein the Head End is further operable to allocate at least one bandwidth resource assignment on the selected downstream channel for communicating with the network node.

22. The system of claim 21 wherein the Head End is further operable to detect that the network node is successfully receiving transmissions on the selected downstream channel;

and

wherein the Head End is further operable to de-allocate at least one bandwidth resource assignment on a different downstream channel which was previously used by the network node for receiving downstream transmissions from the Head End.

23. The system of claim 21 wherein the Head End is further operable to receive a dynamic channel change response from the network node, wherein said dynamic channel change response is generated in response to the network node receiving the dynamic channel change request.

24. The system of claim 21 wherein the Head End is further operable to de-allocate the at least one bandwidth resource assignment in response to not receiving a dynamic channel change response from the network node after a first predetermined time period has elapsed.

25. The system of claim 24 wherein the Head End is further operable to re-transmit the dynamic channel change request to the first node in response to not receiving a dynamic channel change response from the network node after a second predetermined time period has elapsed.

26. The system of claim 23 wherein the Head End is further operable to de-allocate the at least one bandwidth resource assignment in response to detecting that the network node is not successfully receiving transmissions on the selected downstream channel.

27. The system of claim 21 wherein said access network is a wireless network.

28. The system of claim 21 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:

means for transmitting to a network node, via a first downstream channel, a dynamic channel change request, said dynamic channel change request including a request for the node to receive downstream transmissions on a selected downstream channel; and

means for allocating at least one bandwidth resource assignment on the selected downstream channel for communicating with the 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 method comprising:

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

means for analyzing traffic loads on the at least one upstream and downstream channels for accommodating the bandwidth allocation request from the first node;

means for selecting a particular downstream channel for accommodating the bandwidth allocation request from the node; and

means for transmitting to the node, via a first downstream channel, a dynamic channel change request, said dynamic channel change request including a request for the node to receive downstream transmissions on the selected downstream channel.