OPTIMIZING THROUGHPUT OF DATA FRAMES IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) COMMUNICATION NETWORKS

• US 20130250969A1
• Filed: 06/29/2012
• Published: 09/26/2013
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Hui, Jonathan W., Vasseur, Jean-Philippe, Hong, Wei
• Granted Patent: US 9,166,845 B2
• Time in Patent Office: Days
• US Class Current: 370/437
• CPC Class Codes: H04B 2203/5416 by adding signals to the wave form of the power source
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/0033 each allocating device acting autonomously, i.e. without negotiation with other allocating devices
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In one embodiment, a device maintains a predetermined number of high-priority subcarriers for use in communicating high-priority data frames and a predetermined number of low-priority subcarriers for use in communicating low-priority data frames. A data frame is received and a data frame priority is determined for the data frame. If the data frame is determined to be a low-priority data frame, a minimum number of subcarriers, from the low-priority subcarriers, required for communication of the data frame is determined and the data frame is communicated using the minimum number of subcarriers. If the data frame is determined to be a high-priority data frame, a maximum number of subcarriers available, including the high-priority subcarriers and the low-priority subcarriers, is determined and the data frame is communicated using the maximum number of subcarriers.

Claims

1. A method, comprising:

maintaining, using a processor, a predetermined number of first-priority subcarriers for use in communicating first-priority data frames and a predetermined number of second-priority subcarriers for use in communicating second-priority data frames;

receiving a data frame via a network interface;

determining, using the processor, a data frame priority for the data frame;

when the data frame is determined to be a second-priority data frame, determining, using the processor, a minimum number of subcarriers, from the second-priority subcarriers, required for communication of the data frame and communicating the data frame using the minimum number of subcarriers; and

when the data frame is determined to be a first-priority data frame determining, using the processor, the maximum number of subcarriers available, including the first-priority subcarriers and the second-priority subcarriers, for communication of the data frame and communicating the data frame using the determined maximum number of subcarriers available.

2. The method of claim 1, wherein the first-priority subcarriers are maintained by reserving a predetermined number of subcarriers for use only in communication of first-priority data frames.

3. The method of claim 1, wherein the first-priority subcarriers are maintained by verifying that a minimum number of subcarriers will be available for first-priority data frame communication within a predetermined time frame.

4. The method of claim 1, wherein the first-priority subcarriers are maintained by:

sending to a master device via the network interface a suggested minimum number of reserved subcarriers;

receiving from the master device via the network interface a minimum number of first-priority subcarriers to reserve; and

reserving the minimum number of first-priority subcarriers for communication of first-priority data frames.

5. The method of claim 1, wherein the data frame priority is determined by the processor based on an acceptable communication latency that is included in the data frame.

6. The method of claim 1, wherein the data frame priority is included in the data frame.

7. The method of claim 1, wherein the first-priority is high-priority subcarriers and the second-priority is low-priority.

8. The method of claim 1, wherein determining the maximum number of subcarriers comprises:

determining the currently available subcarriers;

determining additional subcarriers that will become available within a predetermined time frame; and

transmitting the first-priority data frame using the currently available subcarriers and the additional subcarriers after the predetermined time frame.

9. An apparatus, comprising:

a network interface adapted to communicate data frames over a network using a plurality of subcarriers;

a processor configured to communicate with the network interface;

a memory configured to communicate with the processor, the memory having instructions stored thereon that, in response to execution by the processor, cause the processor to perform operations comprising;

maintaining a predetermined number of first-priority subcarriers for use in communicating first-priority data frames and a predetermined number of second-priority subcarriers for use in communicating second-priority data frames from the plurality of subcarriers;

receiving a data frame via the network interface;

determining a data frame priority for the data frame;

in response to the data frame being a second-priority data frame, determining a minimum number of subcarriers, from the second-priority subcarriers, required for communication of the data frame and communicating the data frame using the minimum number of subcarriers; and

in response to the data frame being a first-priority data frame determining the maximum number of subcarriers available, including the first-priority subcarriers and the second-priority subcarriers, for communication of the data frame and communicating the data frame using the maximum number of subcarriers.

10. The apparatus of claim 9, wherein the processor maintains first-priority subcarriers by reserving a predetermined number of subcarriers for use only in communication of first-priority data frames.

11. The apparatus of claim 9, wherein the first-priority subcarriers are maintained by verifying that a minimum number of subcarriers will be available for first-priority data frame communication within a predetermined time frame.

12. The apparatus of claim 9, wherein the first-priority subcarriers are maintained by:

sending to a master device via the network interface a suggested minimum number of reserved subcarriers;

receiving from the master device via the network interface a minimum number of first-priority subcarriers to reserve; and

reserving the minimum number of first-priority subcarriers for communication of first-priority data frames.

13. The apparatus of claim 9, wherein the data frame priority is determined based on an acceptable communication latency that is included in the data frame.

14. The apparatus of claim 9, wherein the data frame priority is included in the data frame.

15. The apparatus of claim 9, wherein the first-priority is high-priority and the second-priority is low-priority.

16. The apparatus of claim 9, wherein determining the maximum number of subcarriers comprises:

determining the currently available subcarriers;

determining additional subcarriers that will become available within a predetermined time frame; and

transmitting the first-priority data frame using the currently available subcarriers and the additional subcarriers after the predetermined time frame.

17. A tangible non-transitory computer-readable medium having computer executable instructions stored thereon that, when executed by a computer, cause the computer to perform a method comprising:

maintaining a predetermined number of first-priority subcarriers for use in communicating first-priority data frames and a predetermined number of second-priority subcarriers for use in communicating second-priority data frames from a plurality of subcarriers;

receiving a data frame via a network interface;

determining a data frame priority for the data frame;

in response to the data frame being a second-priority data frame, determining a minimum number of subcarriers, from the second-priority subcarriers, required for communication of the data frame and communicating the data frame using the minimum number of subcarriers; and

in response to the data frame being a first-priority data frame, determining the maximum number of subcarriers available, including the first-priority subcarriers and the second-priority subcarriers, for communication of the data frame and communicating the data frame using the maximum number of subcarriers.

18. The computer-readable medium of claim 17, wherein the maintaining first-priority subcarriers comprises reserving a predetermined number of subcarriers for use only in communication of first-priority data frames.

19. The computer-readable medium of claim 17, wherein the first-priority subcarriers are maintained by verifying that a minimum number of subcarriers will be available for first-priority data frame communication within a predetermined time frame.

20. The computer-readable medium of claim 17, wherein the first-priority subcarriers are maintained by:

sending to a master device via the network interface a suggested minimum number of reserved subcarriers;

receiving from the master device via the network interface a minimum number of first-priority subcarriers to reserve; and

reserving the minimum number of first-priority subcarriers for communication of first-priority data frames.