Adaptive upstream bandwidth estimation and shaping

• US 7,876,696 B2
• Filed: 10/25/2006
• Issued: 01/25/2011
• Est. Priority Date: 01/27/2006
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Kotelba, Marek R.
• Primary Examiner(s): Vu; Huy D
• Assistant Examiner(s): RENNER, BRANDON M
• Application Number:
  US11/586,145
• Publication Number:
  US 20070177626A1
• Time in Patent Office: 1,553 Days
• Field of Search: 370/468, 370/252, 370/352, 709/232
• US Class Current: 370/252
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0015 characterised by the adaptation strategy
• CPC Class Codes: H04L 41/0896 Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76
• CPC Class Codes: H04L 41/5003 Managing SLA; Interaction between SLA and QoS
• CPC Class Codes: H04L 41/5087 wherein the managed service relates to voice services management of VoIP services H04M7/0081
• CPC Class Codes: H04L 43/0829 Packet loss
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

One embodiment of the present invention includes a method for adaptively estimating available upstream bandwidth in a network. The method comprises monitoring data indicative of a number of lost packets at a near-end communication device. The data indicative of a number of lost packets can be periodically transmitted from a far-end communication device. The method also comprises increasing an amount of upstream bandwidth transmission until the monitored data exceeds a threshold. The method also comprises calculating an estimated available upstream bandwidth based on a portion of a maximum amount of the upstream bandwidth transmission.

Claims

1. A method for adaptively estimating available upstream bandwidth in a network, the method comprising:

monitoring data indicative of a number of lost packets at a near-end communication device, the data indicative of a number of lost packets being transmitted from a far-end communication device;

increasing an amount of upstream bandwidth transmission from the near-end device to the far-end device until the monitored data exceeds a first threshold comprising generating purely a plurality of synthetic packets and transmitting a first portion of the plurality of synthetic packets at an increasing rate, wherein the plurality of synthetic packets have no purpose other than network congestion;

calculating an estimated available upstream bandwidth based on a portion of a maximum amount of the upstream bandwidth transmission;

transmitting a second portion of the plurality of synthetic packets at a decreasing amount of bandwidth until the filtered data decreases below a second threshold that is less than the first threshold, upon the monitored data exceeding the first threshold; and

estimating the available upstream bandwidth in response to the monitored data decreasing below the second threshold, the available upstream bandwidth being estimated by the bandwidth estimation logic based on a sum of the amount of bandwidth associated with the synthetic packets and an amount of bandwidth associated with transmitted voice packets.

2. The method of claim 1, wherein calculating the estimated available upstream bandwidth comprises adding the portion of the maximum amount of upstream bandwidth transmission associated with the transmitted synthetic packets and a bandwidth associated with transmitted voice packets.

3. The method of claim 1, wherein the threshold is a first threshold, the method further comprising decreasing the amount of the upstream bandwidth transmission upon the monitored data exceeding the first threshold until the monitored data decreases below a second threshold that is lower that the first threshold.

4. The method of claim 3, wherein the increasing the upstream bandwidth transmission further comprises increasing the upstream bandwidth transmission at a first rate, and wherein the decreasing the upstream bandwidth transmission comprises decreasing the amount of the upstream bandwidth transmission at a second rate that is less than the first rate.

5. The method of claim 1, further comprising:

receiving a plurality of communication link packets transmitted by the far-end communication device, each of the plurality of communication link packets comprising packet loss data indicative of a number of packets lost since a previously transmitted one of the plurality of communication link packets; and

filtering the packet loss data from a plurality of sequential communication link packets to generate the monitored data.

6. The method of claim 5, further comprising updating the filtering of the packet loss data at a rate that does not exceed a rate at which the plurality of communication link packets are received.

7. The method of claim 1, further comprising establishing a nominal value associated with the monitored data in a steady state of operation of the network, the monitoring of the data indicative of a number of lost packets further comprising monitoring the data indicative of a number of lost packets if the monitored data exceeds the nominal value.

8. The method of claim 7, wherein establishing the nominal value comprises throttling down upstream data packet bandwidth associated with at least one downstream computer.

9. The method of claim 1, wherein increasing the amount of the upstream bandwidth transmission comprises increasing the upstream bandwidth transmission by a predetermined bandwidth step size, the method further comprising decreasing the bandwidth step size in response to the monitored data exceeding the second threshold that is less than the first threshold.

10. The method of claim 1, further comprising giving priority to a voice packet or a data packet over a synthetic packet.

11. A network terminal adapter configured to estimate and shape upstream bandwidth, the terminal adapter comprising:

bandwidth estimation logic configured to monitor data indicative of a number of lost packets transmitted from a far-end communication device, the bandwidth estimation logic being further configured to estimate available upstream bandwidth upon the monitored data exceeding a first threshold; and

an upstream traffic shaper configured to allocate upstream bandwidth between voice packets and data packets based on the available upstream bandwidth estimate, said traffic shaper comprising;

a synthetic traffic generator configured to, generate only synthetic packets, the upstream traffic shaper being further configured to transmit the synthetic packets at a bandwidth that increases according to a predetermined step size,

upon the monitored data exceeding the first threshold, the upstream traffic shaper transmits the synthetic packets at a decreasing amount of bandwidth until the filtered data decreases below a second threshold that is less than the first threshold, and

wherein the bandwidth estimation logic estimated the available upstream bandwidth in response to the monitored data decreasing below the second threshold, the available upstream bandwidth being estimated by the bandwidth estimation logic based on a sum of the amount of bandwidth associated with the synthetic packets and an amount of bandwidth associated with the transmitted voice packets.

12. The terminal adapter of claim 11, wherein the bandwidth estimation logic comprises a filter configured to implement a filter algorithm to generate the monitored data, the filter algorithm comprising a first order smoothing coefficient on packet loss data indicative of a number of lost packets transmitted from a plurality of consecutive communication link packets.

13. The terminal adapter of claim 11, wherein the threshold is a first threshold, and wherein the upstream traffic shaper is further configured to decrease the amount of bandwidth of the synthetic packets in the steps from the predetermined size upon the filtered data exceeding a second threshold, the second threshold being less than the first threshold.

14. The terminal adapter of claim 11, wherein the bandwidth estimation logic estimates the available upstream bandwidth during a measurement cycle, such that the upstream traffic shaper throttles upstream data packet bandwidth associated with at least one downstream computer during the measurement cycle to determine a nominal value of the filtered data, such that the bandwidth estimation logic monitors the filtered data upon the filtered data being greater than the nominal value.

15. The terminal adapter of claim 11, wherein the upstream traffic shaper allocates a predetermined default upstream bandwidth for the voice traffic and the data traffic upon the terminal adapter detecting a change in internet protocol address at power-up.

16. A communication system comprising:

a first communication device coupled to a first computer and a first voice communication device, said first communication device comprising;

a synthetic traffic generator configured to generate only synthetic packets; and

a second communication device coupled to a second voice communication device, the second communication device being configured to transmit communication link packets comprising data indicative of a number of lost packets that occur in response to voice transmissions from at least the first voice communication device to the second voice communication device, the first communication device being configured to generate and transmit a first plurality of synthetic packets in an increasing amount of bandwidth, the first communication device monitoring the data indicative of a number of lost packets to generate an available bandwidth estimate for voice and data transmissions from the first communication device to the second communication device in response to the monitored data exceeding a first threshold,

upon the monitored data exceeding the first threshold, the first communication device generates and transmits a second plurality of synthetic packets at a decreasing amount of bandwidth until the filtered data decreases below a second threshold that is less than the first threshold, and

wherein the first communication device estimates the available upstream bandwidth in response to the monitored data decreasing below the second threshold, the available upstream bandwidth being estimated by the bandwidth estimation logic based on a sum of the amount of bandwidth associated with the synthetic packets and an amount of bandwidth associated with transmitted voice packets.

17. The system of claim 16, wherein the first communication device comprises a filter configured to implement a filter algorithm comprising a first order smoothing coefficient on the data indicative of a number of lost packets transmitted from a plurality of consecutive communication link packets.

18. The system of claim 16, wherein the first threshold defines an upper limit for lost packets, and in response to the data indicative of a number of lost packets exceeding the first threshold, the first communication device transmits the synthetic packets at a bandwidth that incrementally decreases until the data indicative of a number of lost packets decreases below a second threshold that is lower than the first threshold.