Section 20: Network Troubleshooting Methodology

Question 1

What are the 7 Steps to Troubleshooting?

Answer 1

1) Identify the problem
2) Establish a theory to determine the cause
3) Test the theory to determine the cause
4) Establish a plan of action to resolve the problem and identify potential effects
5) Implement the solution or escalate as necessary
6) Verify the whole system functionality and if applicable, implement preventive measures
7) Document findings, actions, outcomes, and lesson learned

Question 2

What is Throughput?

Answer 2

Actual speed of data on the network

Question 3

What is a Shielded Twisted Pair (STP)?

Answer 3

Wires are twisted in pairs and surrounded in a metallic shielding to minimize EMI

Question 4

What is an Unshielded Twisted Pair (UTP)?

Answer 4

Number of twists determines how much EMI can be blocked

Question 5

What is a Plenum Cable?

Answer 5

Used when running cables horizontally in a building across a particular level

Question 6

What is a Riser Cable?

Answer 6

Used to run network cables vertically between floors in a building in a cable rise or elevator shaft

Question 7

What is a Rollover/Console Cable?

Answer 7

A type of null-modem cable that is used to connect a computer terminal to a router’s console port

Question 8

What is a Crossover Cable?

Answer 8

Connects two Ethernet devices directly, such as two computers without a switch or a router in between

Question 9

What is Power over Ethernet (PoE)?

Answer 9

Passes electric power over twisted pair Ethernet cable to powered devices

Question 10

What is Attenuation?

Answer 10

Reduction of signal strength between the transmission and receipt of the signal

Question 11

What is Interference?

Answer 11

Occurs when multiple wireless networks communicate on the same channel using the same frequency

Question 12

What is Decibel (dB) Loss?

Answer 12

Measures the amount of signal deterioration we are experiencing on a given connection

Question 13

What is the default pinout for the TIA-568B?

Answer 13

White/Orange - Orange - White/Green - Blue - White/Blue - Green - White/Brown - Brown

Question 14

What do you do if there’s a Bad Port?

Answer 14

Connect a loopback plug to the port on that device and run a test using specialized software

Question 15

What is an Open?

Answer 15

There is nothing on the other end of the connection or there’s a break in the wires between the source and the destination

Question 16

What is a Short?

Answer 16

Indicates there are two wires are connected together somewhere in the connection

Question 17

What is the Activity Light?

Answer 17

Used to show the status of the link when it’s in used

Question 18

What does it mean if the Activity Light is off?

Answer 18

Means there’s no link or no connection being established

Question 19

What does it mean if the Activity Light is solid orange?

Answer 19

Means there’s a link or a connection established with the NIC

Question 20

What does it mean if the Activity Light is blinking orange?

Answer 20

Means there’s data activity occurring over that link or connection

Question 21

When the Link Speed Light is green, what is the speed?

Answer 21

1 Gb/s

Question 22

When the Link Speed Light is orange, what is the speed?

Answer 22

100 Mb/s

Question 23

When the Link Speed Light is off, what is the speed?

Answer 23

10 Mb/s

Question 24

What is a Transceiver?

Answer 24

A transmitter and a receiver combined into a single device that converts a network connection from one type to another

Question 25

What is a **Duplex Mismatch**?

Answer 25

When one device thinks the connection is full duplex and the other thinks it is half duplex

Question 26

What is **Dry Cleaning** regarding **Fiber Optics**?

Answer 26

Using light pressure while rubbing the end face of a fiber optic or connector with a dry-cleaning cloth in one direction

Question 27

What is **Wet Cleaning** regarding **Fiber Optics**?

Answer 27

Moistening a piece of lint-free cloth with a fiber optic cleaning solution and wiping the end face of the cable or connector

Question 28

What is a **Cable Crimper**? What **2 connectors** does it support?

Answer 28

Used to attach the connector to the end of the cable. Supports both RJ-45 and RJ-11 connectors

Question 29

What is a **Punchdown Tool**? What is it used for?

Answer 29

Used to terminate wires on a punch-down block without stripping off the insulation. 66 Block, 110 Block, network jacks, and patch panels

Question 30

What is a **Tone Generator**?

Answer 30

Allows technicians to generate a tone at one end of a connection and use the probe to audibly detect the wire pair connected to the tone generator

Question 31

What is a **Loopback Adapter**?

Answer 31

Connects transmit pins (or fibers) to receive pins (or fiber) to test a network interface

Question 32

What is the **Optical Time Domain Reflectometer (OTDR)**?

Answer 32

Locate breaks in fiber optic cables and provide an estimate of the severity and the distance to the break

Question 33

What is a **Multimeter**?

Answer 33

Checks the voltage or the amperage or the resistance of a copper cable

Question 34

What is a **Cable Tester**?

Answer 34

verifies continuity for each wire in the cable to ensure there are no breaks

Question 35

What is a **Wire Map Tool**?

Answer 35

Like a cable tester, but it works specifically for twisted pair Ethernet cables

Question 36

What is a **Tap**?

Answer 36

A simple device that connects directly to the cabling infrastructure to split or copy packets for use in analysis, security, or general network management

Question 37

What is a **Fusion Splicer**?

Answer 37

A machine that is used to permanently join two fibers together

Question 38

What is a **Spectrum Analyzer**?

Answer 38

A device that measures and displays signal amplitude (strength) as it varies by frequency within its frequency range (spectrum)

Question 39

What are **Snips/Cutters**?

Answer 39

Used to simply cut a piece of cable off a larger spool or run of cable

Question 40

What is a **Cable Stripper**?

Answer 40

Strips the end of the cable to prepare it the attachment of a RJ-45 or other type of connector

Question 41

What is a **Fiber Light Meter**?

Answer 41

A device that provides a continuous wave of stable source of energy for attenuation measurements