2.10 network cabling

Question 1

What is Ethernet Cable?

Answer 1

a standard of network communication using twisted pair cable.

Question 2

What are Network Cables?

Answer 2

Cables to connect network devices to each other, most used today are Ethernet (copper) and fiber optic (glass) cables.

Question 3

What is Ethernet Cable, and what are its common characteristics?

Answer 3

The most common Ethernet cabling in use today is Cat5e UTP. UTP is the abbreviation of Unshielded Twisted Pair. This cable type utilizes four pairs of twisted pair wires within one cable, and two pairs are used to send data, while two pairs are used to receive data.

Question 4

Why is the order of wires inside the connector critical for Ethernet cables to work properly?

Answer 4

Straight-through Ethernet cables are cables where the wire placement is the same on both ends of the cable.

Question 5

What are the two standard wiring schemes for straight-through Ethernet cables?

Answer 5

T568A and T568B.

Question 6

What is a Crossover Ethernet Cable, and how does it differ from a straight-through cable?

Answer 6

A crossover cable has T568A wiring scheme on one side and T568B wiring scheme on the other side. Crossover cables are used to connect similar devices together, such as switch to switch, router to router, switch to hub, hub to hub, computer to router, and computer to computer.

Question 7

What is a Null Modem Cable, and what are its characteristics?

Answer 7

A Null modem cable, also called a rollover cable, is used to connect a PC to a console port on a switch or router. It has an RJ45 connection on one end and a DB9 connection on the other hand. The RJ45 connection plugs into the switch or router, and the DB9 connection connects to a serial port on the computer.

Question 8

What is required for most new computers when using Null Modem cables?

Answer 8

For most new computers, you will need a USB to serial adapter, and some higher-end switches now have micro USB ports for management.

Question 9

What are the speed ratings for different Ethernet Cable Categories?

Answer 9

Category 3 – 10Mbps, Category 4 – 16Mbps, Category 5 – 100Mbps, Category 5e – 1Gbps, Category 6 – 1Gbps, Category 6a – 10Gbps, Category 7 – 100Gbps.

Question 10

How are higher speeds achieved in Ethernet Cables?

Answer 10

Using four pairs of wires rather than just two pairs, increasing the twists per centimeter in the wire.

Question 11

What is the reason for the nylon spline in Cat6 cables?

Answer 11

The nylon spline helps to eliminate crosstalk, which is interference in one circuit that comes from another circuit.

Question 12

What is Shielded Twisted Pair (STP)?

Answer 12

STP is an Ethernet cable that has a protective shielding wrapped around the wires to further prevent interference issues, but STP cables are more expensive and harder to work with because they are not flexible.

Question 13

What is the impact of signal deterioration in Ethernet cables?

Answer 13

Ethernet cables have a length limit of 100 meters before the signal starts to deteriorate (attenuation), attenuation: losing signal strength, to cover greater lengths, the signal has to be regenerated, devices like hubs and switches will regenerate the signal.

Question 14

What is the key feature of Fiber Optic Cables in networking?

Answer 14

To go fast and far at the same time, think about fiber optic cables. Fiber optic is a type of network cable that uses a super thin glass or plastic core to transmit data via a light signal.

Question 15

What are the advantages of Fiber Optic Cables over other cables in terms of interference?

Answer 15

Because fiber optic cables use light rather than electrical signal, they are not affected by RFI (Radio Frequency Interference) or EMI (Electro-magnetic Interference).

Question 16

What are the two main types of fiber optic cable in use today?

Answer 16

Single mode, Multimode.

Question 17

What are the characteristics of Single Mode Fiber Optic Cable?

Answer 17

Smaller 9-micron core and a 125-micron cladding, only allows one mode of light to traverse through the cable, which lowers attenuation and allows the signal to travel further. Used for longer distance cable runs, such as over a WAN. Higher bandwidth than multimode cabling, more expensive transceiver cost, cheaper installation costs.

Question 18

What are the characteristics of Multimode Fiber Optic Cable?

Answer 18

Larger 50 or 62.5-micron core and a 125-micron cladding (see slide 20), allows multiple modes of light to traverse through the cable, allowing more data to pass through at a given time. Typically used within the data center with LANs. High bandwidth and speed over short to medium distances, signal quality is reduced over long distances, cheaper transceiver cost, more expensive installation costs.

Question 19

What are the three main types of fiber optic cable connectors in use today?

Answer 19

ST – Straight Tip, LC – Lucent Connector, SC – Standard Connector.

Question 20

What are the characteristics of Simplex, Half Duplex, and Full Duplex in networking?

Answer 20

Simplex: Network communication only happens in one direction, for example, radio or television. Half Duplex: Network communication happens in both directions but only one direction at a time, for example, walkie-talkie. Full Duplex: Network communication takes place in both directions at the same time, for example, a phone call.

Question 21

What is Network Topology in networking?

Answer 21

Network topology is the way computers and other network peripherals are arranged and connected in a network.

Question 22

What are four common network topologies?

Answer 22

Bus, Ring, Mesh, Star.

Question 23

What is Bus Topology in networking?

Answer 23

Every computer or other network device is connected to a single network cable.

Question 24

What is Ring Topology in networking?

Answer 24

Computers and other network devices are connected to each other, and the last device is connected to the first device to make a ring.

Question 25

What is Mesh Topology in networking?

Answer 25

Each computer or network device is connected to every other computer or device.

Question 26

What is Star Topology in networking?

Answer 26

All computers or network devices are connected to a centralized device.

Question 27

What are the advantages and disadvantages of Bus Topology in networking?

Answer 27

Advantages: Cheap and easy to implement, requires less cable, does not use any specialized network equipment.
Disadvantages: Network disruption when computers are added or removed, a break in the cable will prevent all systems from accessing the network, difficult to troubleshoot.

Question 28

What are the advantages and disadvantages of Ring Topology in networking?

Answer 28

Advantages: Cable faults are easily located, making troubleshooting easier, ring networks are moderately easy to install.
Disadvantages: Expansion to the networks can cause network disruption, a single break in the cable can disrupt the entire network.

Question 29

What are the advantages and disadvantages of Mesh Topology in networking?

Answer 29

Advantages: Provides redundant paths between devices, the network can be expanded without disruption to current users.
Disadvantages: Requires more cable than the other LAN topologies, complicated implementation.

Question 30

What are the advantages and disadvantages of Star Topology in networking?

Answer 30

Advantages: Easily expanded without disruption to the network, cable failure affects only a single user, easy to troubleshoot and isolate problems.
Disadvantages: Requires more cable, a central connecting device allows for a single point of failure, more difficult to implement.

Question 31

What is the impact of signal deterioration in Ethernet cables?

Answer 31

Ethernet cables have a length limit of 100 meters before the signal starts to deteriorate (attenuation), attenuation: losing signal strength, to cover greater lengths, the signal has to be regenerated, devices like hubs and switches will regenerate the signal.