Dynamically allocating channel bandwidth between interfaces

• US 8,160,098 B1
• Filed: 01/14/2009
• Issued: 04/17/2012
• Est. Priority Date: 01/14/2009
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Liu, Tong, Yan, Anlu, Mikkelson, Chad, Ding, Aimin
• Primary Examiner(s): Sefcheck, Gregory
• Assistant Examiner(s): Mitchell, Daniel
• Application Number:
  US12/353,946
• Time in Patent Office: 1,189 Days
• Field of Search: None
• US Class Current: 370/468
• CPC Class Codes: H04L 47/522 Dynamic queue service slot or variable bandwidth allocation
• CPC Class Codes: H04L 47/626 channel conditions
• CPC Class Codes: H04L 47/6275 based on priority
• CPC Class Codes: H04L 47/762 triggered by the network
• CPC Class Codes: H04L 47/822 Collecting or measuring resource availability data

Abstract

In one example, a bandwidth allocation device allocates physical channel bandwidth between local interfaces. Thereafter, at a polling time, the bandwidth allocation device determines whether there is communication activity between each local interface and the physical channel. The bandwidth allocation device can then dynamically reallocate the physical channel bandwidth at the polling time according to the communication activity determinations.

Claims

1. An article of manufacture including a computer-readable memory having instructions stored thereon that, in response to execution by a computing device, cause the computing device to perform operations comprising:

passing wideband packets from a first physical queue to a wideband interface for distribution over a plurality of physical Radio Frequency (RF) channels;

passing narrowband packets from a second physical queue to a narrowband interface for transmission over a shared one of the plurality of physical RF channels;

using a scheduler coupled to the wideband interface and the narrowband interface, instantiating traffic flow between the wideband interface and the shared one of the plurality of physical RF channels using a first logical buffer and instantiating traffic flow between the narrowband interface and the shared one of the plurality of physical RF channels using a second logical buffer, wherein using the scheduler further comprises allocating bandwidth of the shared physical RF channel to both the wideband interface and the narrowband interface at a given instant;

identifying when communication from one of the interfaces to the shared physical RF channel is inactive; and

varying the allocation of the bandwidth of the shared physical RF channel between the interfaces in response to the identification, wherein the bandwidth allocation is varied according to parameters of the logical buffers.

2. The article of manufacture of claim 1, further comprising

a packet queue arbiter configured to control transfer of the packets from the physical queues to the interfaces.

3. The article of manufacture of claim 2, wherein operation of the packet queue arbiter is unaffected by the varying of the allocation of the bandwidth of the shared physical RF channel between the interfaces.

4. The article of manufacture of claim 1, wherein the operations further comprise:

identifying a guaranteed data rate for each of the logical buffers;

wherein the varied allocation is based at least in part on the identified guaranteed data rates.

5. The article of manufacture of claim 4, wherein the operations further comprise:

identifying a priority weighting for each of the logical buffers;

wherein the varied allocation is based at least in part on the identified priority weightings if there is excess bandwidth available after accounting for the guaranteed data rates.

6. The article of manufacture of claim 5, wherein the operations further comprise:

identifying maximum values for each of the logical buffers;

wherein the amount of bandwidth allocated to each interface in the varied allocation is capped by the identified maximum values.

7. The article of manufacture of claim 1, wherein the operations further comprise:

identifying a maximum bandwidth capability of the shared physical RF channel;

wherein the varied allocation is based at least in part on the identified maximum bandwidth capability.

8. A method, comprising:

passing wideband packets from a first physical queue to a wideband interface for distribution over a plurality of physical Radio Frequency (RF) channels;

passing narrowband packets from a second physical queue to a narrowband interface for transmission over a shared one of the plurality of physical RF channels;

using a scheduler coupled to the wideband interface and the narrowband interface, instantiating traffic flow between the wideband interface and the shared one of the plurality of physical RF channels using a first logical buffer and instantiating traffic flow between the narrowband interface and the shared one of the plurality of physical RF channels using a second logical buffer, wherein using the scheduler further comprises allocating bandwidth of the shared physical RF channel to both the wideband interface and the narrowband interface at a given instant;

identifying when communication from one of the interfaces to the shared physical RF channel is inactive; and

varying the allocation of the bandwidth of the shared physical RF channel between the interfaces in response to the identification, wherein the bandwidth allocation is varied according to parameters of the logical buffers.

9. The method of claim 8, wherein the plurality of RF channels extends from a Cable Modem Termination System (CMTS).

10. The method of claim 8, further comprising:

identifying a guaranteed data rate for each of the logical buffers;

wherein the varying of the allocation of the bandwidth of the shared physical RF channel between the interfaces is based at least in part on the identified guaranteed data rates.

11. The method of claim 10, further comprising:

identifying a priority weighting for each of the logical buffers;

wherein the varying of the allocation of the bandwidth of the shared physical RF channel between the interfaces is based at least in part on the identified priority weighting if there is excess bandwidth available after accounting for the guaranteed data rates.

12. The method of claim 11, further comprising:

Identifying maximum values for each of the logical buffers;

Wherein the amount of bandwidth allocated to each interface in the varied allocation is capped by the identified maximum values.

13. The method of claim 8, further comprising:

identifying a maximum bandwidth capability of the shared physical RF channel;

wherein the varying of the allocation of the bandwidth of the shared physical RF channel between the interfaces is based at least in part on the identified maximum bandwidth capability.

14. The method of claim 8, further comprising:

buffering a plurality of bonded channel flows and a plurality of non-bonded channel flows; and

arbitrating the release of packets from the buffer to the wideband interface and the narrowband interface.

15. The method of claim 14, wherein the packets are released according to a schedule that is unaffected by the varying of the allocation of the bandwidth of the shared physical RF channel between the interfaces.

16. The method of claim 14, wherein the flows are formatted according to the Data Over Cable Service Interface Specification (DOCSIS).

17. The method of claim 8, wherein the physical RF channels extend to a plurality of cable modems.