Wired Intelligent Edge (Campus Switching and Routing)

Answer- Time-Domain Reflectometer (TDR) is a measurement technique used to characterize and locate faults in metallic cables such as twisted pair. TDR transmits a short rise electric pulse across the conducting cable and if the cable is properly terminated, the entire electric pulse is absorbed on the other end. If any faults exist in the cable, some of the incident signal is sent back towards the source. TDR also:

• Locates the position of faults within meters
• Detects and reports open circuits, short circuits, and impedance mismatches in a cable
• Detects pair swap (straight/crossover) on each pair of cable in twisted pair cable
• Detects pair polarity (positive/negative) on each channel pairs in a cable

Use this command to execute a TDR diagnostic test on a specific gigabitethernet interface.

(host) (config)# run diagnostics interface gigabitethernet <slot/module/port> cable

Use the following command to view the test results for the Time-Domain Reflectometer (TDR) cable diagnostics:

(host)# show diagnostics interface gigabitethernet

Tested in 7.3.2.2 and 7.4.0.1 image version.