System for dynamically determining effective speed of a communication link

• US 6,215,774 B1
• Filed: 10/24/1997
• Issued: 04/10/2001
• Est. Priority Date: 03/25/1997
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Tso, Michael Man-Hak, Knauerhase, Robert Conrad
• Primary Examiner(s): Patel, Ajit
• Application Number:
  US08/957,468
• Time in Patent Office: 1,264 Days
• Field of Search: 370/250, 370/252, 370/253, 370/389, 370/235, 370/236, 370/468, 709/232, 709/233, 709/247, 709/202, 709/203, 709/217, 709/227, 709/228, 709/231, 709/246, 709/503, 709/500
• US Class Current: 370/252
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 43/0888 Throughput
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route
• CPC Class Codes: H04L 43/50 Testing arrangements

Abstract

A method for determining effective link speed for communications from a first device to a second device coupled by a communications link includes the steps of transmitting a packet from the first device to the second device; receiving a responsive packet at the first device; and determining an effective link speed for communications between the first device and the second device using a period of time between the transmission and receipt.

Claims

1. A method for enhancing data communications from a first device to a second device coupled by a communications link, said method comprising the steps of:

receiving at a first device a request to transmit a data object to a second device;

transmitting a test packet from the first device to the second device in response to receiving said request;

receiving a responsive test packet at the first device;

determining an effective link speed for communications between the first device and the second device using a period of time between said transmission and said receipt of test packets;

transcoding the requested data object to optimize its transmission to the second device based upon the effective link speed; and

transmitting the transcoded data object to the second device.

2. The method of claim 1, further comprising the step of storing the determined effective link speed.

3. The method of claim 2, further comprising the steps of:

repeating said steps of transmitting a test packet, receiving a responsive test packet, and determining an effective link speed to determine a current effective link speed; and

updating said stored effective link speed based upon the current effective link speed.

4. The method of claim 3, wherein said stored effective link speed is updated periodically.

5. The method of claim 1, wherein the transmitted test packet has a predetermined size, said effective link speed comprising a measurement of a quantity of data transmitted per unit of time.

6. The method of claim 1, wherein the first device comprises a network client and the second device comprises an intermediate device for routing a communication from the network client to a predetermined network server, said method further comprising the step of determining a network address associated with the second device.

7. The method of claim 6, wherein the first device comprises a network client capable of selectively communicating with a network server through any of a plurality of intermediate routing devices, said method further comprising the steps of:

determining an effective link speed between the first device and each of the plurality of intermediate routing devices; and

selecting one of the plurality of intermediate routing devices for a communication from the network client to the network server according to said determined effective link speeds.

8. The method of claim 1, wherein said steps of transmitting a test packet, receiving a responsive test packet, and determining an effective link speed are repeated for a plurality of iterations, and said effective link speed comprises an average derived from said plurality of iterations.

9. The method of claim 8, further comprising the step of rejecting an iteration having a period of time outside of a predetermined range.

10. The method of claim 1, wherein said steps of transmitting a test packet, receiving a responsive test packet, and determining an effective link speed are performed upon demand by the first device upon detection of a predetermined condition of the communications link between the first device and the second device.

11. The method of claim 10, wherein said predetermined condition comprises an idle condition.

12. The method of claim 1, wherein said step of determining an effective link speed comprises measuring effective usable bandwidth between the first and second devices.

13. The method of claim 12, wherein said step of determining an effective link speed further comprises measuring latency between the first and second devices.

14. The method of claim 1, wherein said effective link speed comprises a measure of latency between the first and second devices.

18. The method of claim 1, wherein said transcoding comprises scaling the data object.

19. The method of claim 1, wherein said transcoding comprises compressing the data object.

20. The method of claim 1, wherein said transcoding comprises enhancing the data object.

21. The method of claim 1, wherein the first device and second device are capable of communicating over any of a plurality of communications links, said method further comprising determining an effective link speed for each of said plurality of communications links.

22. The method of claim 21, further comprising selecting a communications link having a fastest effective link speed for the data communication from the first device to the second device.

15. A set of instructions for enhancing data communications with a network device over a communications link, the set of instructions being stored on a medium for execution by a computer and comprising instructions for:

receiving a request to transmit a data object to the network device;

transmitting a test packet to the network device over the communications link;

receiving a responsive test packet from the network device over the communications link;

determining an effective link speed from a time period between said transmission and said receipt of test packets;

transcoding the requested data object to optimize its transmission to the network device based upon the effective link speed; and

transmitting the transcoded data object to the network device.

16. The set of instructions of claim 15, wherein said storage medium comprises a magnetic storage device.

17. The set of instructions of claim 15, wherein the storage medium comprises a memory installed in the computer.