Physical Media Test Equipment
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Physical Media Test Equipment
S
tarting at the bottom and working up, we begin with Layer 1
connectivity testing. It is amazing how many network problems can
actually be solved by testing and then resolving wiring problems.
In this section you will learn about several different types of physical
media testing equipment. These include:
Multimeters
Cable testers
Time domain reflectors and optical TDRs
Digital interface testing tools
Multimeters and Cable Testers
There is a large variety of physical media testing equipment. The most basic
tools are multimeters and cable testers.
Multimeters
measure voltage, resistance, and current. They work with
electrical-based cabling and can be used to test for physical connectivity.
Cable testers
can be very general or they can be made for a specific type
of cable. Some cable testers have adapters that allow them to test a wide
range of cables. Cable testers are made for electrical and optical cable.
Different from multimeters, cable testers can give the user much more
information regarding the cable being tested. Here are some examples of the
attributes that are reported by a cable tester:
Electrical connectivity
Open pairs
Crossed pairs
Out of distance specification
Out of decibel specification (for optical cable), meaning signal/noise is
out of acceptable specifications
Cross talk
Attenuation
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