1.3.3 Networks

Question 1

what is a network?

Answer 1

two or more computers connected together that transmit data

Question 2

what are protocols?

Answer 2

sets of rules defining how two devices communicate with each other

Question 3

why are protocols standard?

Answer 3

so devices from different manufacturers don’t have problems communicating

Question 4

why is protocol layering used?

Answer 4

-breaks tasks down into manageable units
-to apply protocols in order / one after the other
-to provide independence of layers

Question 5

what is the Internet?

Answer 5

a global network of interconnected networks

Question 6

what does TCP stand for?

Answer 6

Transmission Control Protocol

Question 7

what does IP stand for?

Answer 7

Internet Protocol

Question 8

what is the function of the application layer during data transmission?

Answer 8

specifies what protocols need to be used to relate the application to what it’s being used for

Question 9

what is the role of the transport layer during data transmission?

Answer 9

establishes an end-to-end connection between the source and recipient computers
(it also splits up the data into packets)

Question 10

what is the role of the network layer during data transmission?

Answer 10

adds the source and destination IP address

Question 11

what does the application layer do when it receives data?

Answer 11

presents data in the form it was sent

Question 12

what does the transport layer do when it receives the data?

Answer 12

removes the port number and reassembles the packets

Question 13

what does the network layer do when it receives the data?

Answer 13

removes the IP address

Question 14

what does the link layer do when it receives the data?

Answer 14

removes the MAC addresses

Question 15

what is a Local Area Network?

Answer 15

a network spread over a small geographical area/ positioned on a single site

Question 16

what is a Wide Area Network?

Answer 16

a network spread over a large
geographical area, usually requiring
extra hardware

Question 17

what does DNS stand for?

Answer 17

Domain Name System

Question 18

what is DNS?

Answer 18

the method of naming internet resources (com, .uk etc)

Question 19

what is circuit switching?

Answer 19

the process of creating a direct link
between two devices and transferring data the entire duration of the link

Question 20

what is a requirement of circuit
switching?

Answer 20

the transfer and download rates must be identical on both devices

Question 21

what is a requirement of circuit
switching?

Answer 21

the transfer and download rates must be identical on both devices

Question 22

what is packet switching?

Answer 22

a method of communicating packets of data across a network

Question 23

what are benefits of packet switching?

Answer 23

-multiple methods to ensure data arrives correctly
-multiple methods to arrive to destination, if one breaks can always go through another route
-transfer packets over a very large network

Question 24

what are drawbacks of packet switching?

Answer 24

time is spent deconstructing
and reconstructing the packets

Question 25

what are benefits of circuit switching?

Answer 25

-data arrives in logical order which results in a quicker reconstruction of data -enables two users to hold a call without any delay in speech

Question 26

what are drawbacks of circuit switching?

Answer 26

-bandwidth is wasted during periods when no data is sent -devices must transfer and download at the same rate -switches introduce electrical interference which can corrupt or destroy data

Question 27

what does the header of a data packet contain?

Answer 27

- the sender and recipient IP addresses - protocols being used - order of the packets - The time to live / hop limit

Question 28

what does the packet payload contain?

Answer 28

the raw data

Question 29

what does the packet trailer contain?

Answer 29

the checksum or cyclic redundancy check

Question 30

what is client-server networking?

Answer 30

a relationship between terminals (computers) and a single server which allows them to communicate, and share resources

Question 31

what are benefits of client-server networking?

Answer 31

-increased security -central single backups -data and resources can be shared

Question 32

what are drawbacks of client-server networking?

Answer 32

-expensive to set up -trained staff are required to maintain the network

Question 33

what is peer-to-peer networking?

Answer 33

a network where the terminals are all connected to each other to share resources

Question 34

what are benefits of peer-to-peer networks?

Answer 34

-cheaper to set up -easy to share resources -easy to maintain

Question 35

what are drawbacks of peer-to-peer networks?

Answer 35

-can be used to contribute towards piracy -each computer has to be backed up independently