Chapter 2 - Cabling and Topology

Question 1

Bus Topology

Answer 1

Connected all computers in a line using a single cable
Entire network stops working if cable breaks at any point

Question 2

Ring Topology

Answer 2

Connected all computers with a ring of cable
Entire network stops working if cable breaks at any point

Question 3

Star/Hub and Spoke Topology

Answer 3

Used a central connection box for all computers on the network
Offers fault tolerance, if one cable broke all the other computers could still communicate with the central point
Not very successful because Bus/Ring popular and inexpensive

Question 4

What are the drawbacks of Bus and Ring Topologies?

Answer 4

Entire network stops working if cable breaks at any point

Question 5

Physical Topology

Answer 5

How the cables physically look

Question 6

Logical Topology

Answer 6

How the signals travel electronically

Question 7

Mesh Topology

Answer 7

Every computer connects to every other computer via two or more routes

Question 8

Partially Meshed

Answer 8

At least two machines have redundant connections, but not all machines are directly connected

Question 9

Fully Meshed

Answer 9

Every computer connects to every other computer

Question 10

Coaxial Cable

Answer 10

Contains central copper conductor wire surrounded by insulating material which is then surrounded by a braided metal shield
Shields data transmissions from EMI

Question 11

F-type Connector

Answer 11

Connector that screws in

Question 12

All coaxial cables have a ___ rating

Answer 12

Radio Guide (RG)

Question 13

Ohm Rating

Answer 13

Relative measure of resistance on the cable
Only important measure of coax

Question 14

Twinaxial Cable

Answer 14

Type of coax that contains two central copper conductors wrapped around a single shield
Generally used between equipment in a rack, like switches

Question 15

When twinaxial cable is used between equipment in a rack, it is called ___

Answer 15

Directly attached cable (DAC)

Question 16

Twisted Pair

Answer 16

Each pair in cable works as a team either transmitting or receiving data.

Question 17

What is the benefit of cable using a pair rather than a single wire?

Answer 17

Reduces crosstalk

Question 18

STP

Answer 18

Shielded Twisted Pair
Twisted pairs surrounded by shielding to protect against EMI

Question 19

UTP

Answer 19

Unshielded Twisted Pair
Twisted pairs surrounded by a plastic jacket. No protection against EMI, so when installing must be careful.
Much less expensive

Question 20

Cat Ratings

Answer 20

Designed to help network designers get the right cable for the right technology
Rated in megahertz (MHz)

Question 21

MHz

Answer 21

Megahertz
Indicates highest frequency cable can handle

Question 22

Bandwidth

Answer 22

Maximum amount of data that goes through the cable per second

Question 22

RJ-45

Answer 22

Common name for UTP cable connectors.
This name is incorrect but has become so common its now the standard name.
True name is 8 Position 8 Contact (8P8C)

Question 23

Fiber Optic Cable

Answer 23

Transmits light instead of electricity. Can be regular or laser light.
Requires two cables, one for sending, one for receiving.

Question 24

Where is fiber optic especially beneficial?

Answer 24

Areas with high EMI
Long distance transmissions

Question 25

What does fiber optic cable consist of?

Answer 25

Core - glass fiber itself
Cladding - part that makes light reflect down the fiber
Buffer
Insulating Jacket

Question 26

Multimode Fiber

Answer 26

Uses LEDs to send light signals

Question 27

Single Mode Fiber

Answer 27

Uses laser signals

Question 28

Modal Distortion

Answer 28

Signals sent at the same time don’t arrive at the same time because the paths differ slightly in length
Single Mode Fiber prevents this

Question 29

Nanometers (nm)

Answer 29

Measurement of light wavelength
Fiber optic cabling rated in nanometers

Question 30

PVC

Answer 30

No significant fire protection, if burned it creates a lot of smoke and fumes

Question 31

Plenum

Answer 31

Creates way less smoke and fumes than PVC but is 3-5x more expensive.
Required for most city ordinances

Question 32

IEEE

Answer 32

Institute of Electrical and Electronics Engineers
Defines industry wide standards that promote the use and implementation of technology

Question 33

IEEE 802 Committee

Answer 33

Defines frames, speeds, distances, and types of cabling to use in a network environment

Question 34

802.1

Answer 34

Higher Layer LAN protocols

Question 35

802.3

Answer 35

Ethernet

Question 36

802.11

Answer 36

Wireless LAN

Question 37

802.15

Answer 37

Wireless Personal Area Network