Method and system for performing time domain reflectometry contemporaneously with recurrent transmissions on computer network

• US 6,657,437 B1
• Filed: 11/15/1999
• Issued: 12/02/2003
• Est. Priority Date: 10/04/1999
• Status: Expired due to Term

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: Vigilant Networks, LLC
• Inventors: LeCroy, Dorian, Judell, Neil, Richardson, William M.
• Primary Examiner(s): Snow, Walter E.
• Assistant Examiner(s): Benson, Walter
• Application Number:
  US09/440,293
• Time in Patent Office: 1,478 Days
• Field of Search: 324/527, 324/533, 324/534, 324/557, 370/320, 702/79, 209/224
• US Class Current: 324/534
• CPC Class Codes: G01R 31/086 in power transmission or distribution networks, i.e. with interconnected conductors
• CPC Class Codes: H04L 43/50 Testing arrangements

Abstract

A method for performing time domain reflectometry contemporaneously with recurrent transmissions, such as idle transmissions, on a computer network, such as a 100 BASE T protocol network is disclosed. This method comprises detecting the recurrent transmissions and then storing representations of those transmissions. A probe signal, such as a TDR signal, is then generated onto the computer network during the recurrent transmissions. A response of the network to the probe signal combined with the recurrent transmissions is then detected. The signal transmission characteristics of the network are then analyzable based on the response to the probe signal using the stored representations of the recurrent transmissions, using deconvolution, for example.

Claims

1. A method for performing time domain reflectometry contemporaneously with recurrent transmissions on a computer network, the method comprising:

detecting the recurrent transmissions;

storing representations of the recurrent transmissions;

generating a probe signal on the computer network during the recurrent transmissions;

detecting a response of the network to the probe signal combined with the recurrent transmissions; and

analyzing signal transmission characteristics of the network based on the response to the probe signal using the stored representations of the recurrent transmissions.

2. A method as described in claim 1, further comprising detecting a response of the computer network to a probe signal while the computer network is inactive.

3. A method as described in claim 2, wherein the computer network comprises a link on which the time domain reflectometry is being performed, and the step of detecting the response of the computer network to a probe signal while the computer network is inactive comprises detecting a response of a network device maintaining the link.

4. A method as described in claim 3, wherein the network device is a hub.

5. A method as described in claim 1, wherein the step of storing representations of the recurrent transmissions comprises storing representations of the recurrent transmissions based on transmissions detected prior to the generation of the probe signal.

6. A method as described in claim 1, wherein the step of storing representations of the recurrent transmissions comprises storing representations of the recurrent transmissions based on transmissions detected after to the generation of the probe signal.

7. A method as described in claim 1, wherein the computer network is a continuous transmission network, and the steps of detecting and storing the recurrent transmissions comprises detecting and storing an idle signal.

8. A method as described in claim 1, wherein the step of detecting the recurrent transmissions comprises performing hardware equalization of the transmissions.

9. A method as described in claim 1, wherein the step of analyzing the signal transmission characteristics of the network comprises removing the contribution of the recurrent transmissions to the detected combined response of the network.

10. A method as described in claim 1, wherein removing the contribution of the recurrent transmissions comprises performing deconvolution.

11. A method as described in claim 1, further comprising multiple links of continuous transmission computer networks and prior to said detecting step, comparing transmission on the links of the computer networks to stored idle signals for the computer networks.