network topologies

Question 1

local area network

Answer 1

2 or more computers connected together within a small geographical areae

Question 2

example of LAN

Answer 2

house network

Question 3

bus topology

Answer 3

an arrangement where nodes are connected in a daisy chain by a single central communications channel

Question 4

star topology

Answer 4

an arrangement where a central node or hub provides a common connection point for all other nodes

Question 5

what is a standalone

Answer 5

a computer which is not connected to any other computers

Question 6

how does a bus network operate

Answer 6

• All nodes are connected to a single backbone cable
• Each end of the backbone is connected to either a terminator or a - computer which stops signals ‘bouncing back’
• Data is sent in one direction at a time only
• Only one computer can transmit successfully at any one time

Question 7

what is CSMA/CD technology

Answer 7

CSMA with Collision Detection (CSMA/CD) detects two nodes attempting to transmit simultaneously
Both nodes cease transmission and wait a random amount of time before reattempting
CSMA with Collision Avoidance (CSMA/CA) is used with wireless networks

Question 8

bus network topology advantages

Answer 8

cheap
devices can be easily added
good for small networks

Question 9

bus network topology disadvantages

Answer 9

main cable is a point of failure
limited cable length
performance degrades with heavy use owing to data collisions
poor security

Question 10

how does a star network operate

Answer 10

the computers are all connected directly to a central node
this is often a hub or switch

Question 11

what is a switch

Answer 11

sends each communication to the specific computer it is intended for

Question 12

what is a hub

Answer 12

broadcasts the message to every computer on the LAN

Question 13

mac addressing

Answer 13

Every networked device contains a Network Interface Card (NIC)
Each NIC is attributed a unique Media Access Control (MAC) address hardcoded in manufacture
A switch holds all of the MAC addresses for each device connected to it and uses these to direct packets of data to the correct device

Question 14

star network topology advantages

Answer 14

it is easy to isolate problems
good performance
more secure if a switch is used as data is sent only to the recipient

Question 15

star network topology disadvantages

Answer 15

can be expensive to set up because of the length of cable required
the central device is a point of failure

Question 16

physical topology

Answer 16

defines how the devices are physically connected

Question 17

logical topology

Answer 17

defines how the devices communicate across the physical topologies

Question 18

how can physical and logical differ

Answer 18

A network wired in star topology can behave logically as a bus network by using a bus protocol and appropriate physical switching