Network eavesdropping detection

Patent metadata

Field	Value
Publication number	US-9130984-B2
Application number	US-201313896550-A
Country	US
Kind code	B2
Filing date	May 17, 2013
Priority date	May 17, 2013
Publication date	Sep 8, 2015
Grant date	Sep 8, 2015

Abstract

In one implementation, network taps are detected using impedance measurements from a network. A network device is configured to calculate a baseline impedance as a function of a sequence of impedance values. As impedance measurements subsequent to the sequence of impedance values are received, the network device is configured to calculate a difference between the impedance measurement and the baseline impedance. The network device generates a network tap warning message when the difference between the impedance measurement and the baseline impedance exceeds a threshold. The network device may be an endpoint computer, a data switch, or an external device remote from the network.

First claim

I claim:

1. A method comprising:
sending a series of impulse signals over a communication line for a time period;
receiving a series of impedance values for the communication line over the time period in response to the series of impulse signals;
calculating a baseline impedance as a function of the series of impedance values;
receiving an impedance measurement generated after the time period;
calculating a difference between the impedance measurement and the baseline impe…

Assignees

• Cisco Tech Inc

Inventors

• Foley John

Classifications

• H04L63/1425 Primary

  Electricity · mapped topic

• H04L63/1475

  Electricity · mapped topic