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Flashcards in Networks And E-communication Deck (97)
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1

Nodes

Networking consists of computing devices

2

LAN

Local area network

Describes the networking capabilities of a group of computers close to each other

Share files, printers, applications

3

What does a network need

Hardware that acts as a source or sender to a destination or reciever

4

LANS use cables like?

Inexpensive cables

Ethernet cables

Network adaptors

Switches

5

What's does network hardware include

Nodes(computing devices)

NICS(network interface cards to which media connects(cables)

Connecting devices (switch, bridges, routers, repeaters

6

What are nodes connected with

Transmission media(network media)

7

3 types of cables

Coaxial cable

Twisted pair cable

UnshieldedTwisted pair cable( Ethernet cable)

8

Are coaxial cables still used today and why are they good??

No

Expensive

Most resistant to interference/cross talk

Less noise > less repeaters

9

Describe coaxial twisted pair cables

Core of copper ,surrounded with insulation , braided metal shielding with outer cover

10

Describe twisted pair cable

Consists of two insulated strands of copper twisted around each other

11

Why is the twisting so effective

To prevent electrical interference from other cables and outside sources

Effect against crosstalk

12

Another term for Unshielded Twisted pair(UTP)


Ethernet cables

13

What is a problem with all types of cabling

Crosstalk

14

What is crosstalk

Signals from one line interfering with signals from another line

15

Is UTP susceptible for crosstalk??

Yes

16

What are the problems for copper cables

Attenuation(signal strength is lost over distances)

Electro-Magnetic interference (signals from other sources can interrupt the traveling signals in copper cables)

Eavesdropping( signals can be intercepted by outsiders)

Crosstalk( signals can interfere with each other )

17

What is fibre optic?

Communication cable that carries digital data in fonts of pulses of light

No electrician impulses

Cannot be stolen

18

Why is fibre optic effective

High speed, high capacity data transmissions because of lack of attenuation

19

How does fibre optic work

For how long can they carry a signal


Two strands

One to transmit data
Other to receive data

For many kilometers

20

What is signal mode

One mode of transmission

Eliminates overlapping of light waves causing distortion

21

What is multi mode

Light is dispersed into many paths

light/data clashes and makes data incomplete and unclear

22

What are NICS

Network interface cards

Connection between a network cable and a computer

Unique address(MAC) to each computer so that it can be distinguished from all the other network cards on the internet

MAC -media access control if linked to the IP (internet protocol) address

MAC and IP addresses are stored in the ARP(address resolution protocol) ram of the NIC

ARP also stores Mac addresses of other devices so that it knows where the data is coming from

23

What does the term topology mean


The physical set up of a network , how the network devices are connected

24

3 kinds of topologies

Star ring bus

25

Combination of topology

Hybrid topology such as star-ring topology

26

What is a star topology

The cable from the NIC to a hub or a switch has a signal that's boosted to every computer connected to it through UTP cables or Fibre Optic

27

Advantages of Star topology

Easy to set up and maintain

Prob with one, only stays with one

Add/ remove no prob

Common

28

Disadvantages of Star topology

Large amounts of cabling from nic to hub/switch

Hud/switch fails all fails

HUD/siwtch is costly

29

What is a bus topology

All nodes connect to a single cable which has a terminator at the end to stop the signals from bouncing out. Coaxial cables

30

Advantages of a bus topology

Less cabling

No hub/switch to boost signals

Easy to extend by adding nodes but this disrupts the network