4.9: section 6: communication: technology and networking

Question 1

define serial transmission

Answer 1

serial transmission is when bits are sent one after another over a single wire

Question 2

define parallel transmission

Answer 2

multiple bits are sent over parallel wires simultaneously

Question 3

what are the advantages of serial over parallel transmission

Answer 3

serial can be used over long distances
serial is cheaper and less complicated
serial suffers from little interference at higher frequencies
serial signal frequencies can be much higher
serial doesnt suffer form skew or crosstalk

Question 4

define asynchronous data transmission

Answer 4

each byte is sent separately when its ready with a parity bit, a stop bit and a start bit.

Question 5

define synchronous data transmission

Answer 5

data is sent at regular intervals timed by a clocking signal which allows for constant reliable transmission. parallel communication often uses synchronous transmission

Question 6

what are start and stop bits for

Answer 6

start and stop bits are used to make clear when a new set of data has arrived

Question 7

define bit rate

Answer 7

bit rate is the number of bits transferred between devices in one second

Question 8

define baud rate

Answer 8

the rate of signal state change in a communication channel

Question 9

define bandwidth

Answer 9

a measure of the maximum capacity of a given communication channel

Question 10

define latency

Answer 10

the time delay before a component in a computer system responds to an instruction

Question 11

define protocol

Answer 11

a set of rules relating to communication between devices that allow then to communicate

Question 12

what is the relationship between bit rate and baud rate

Answer 12

bit rate can be higher than baud rate if more than one bit is encoded into each signal

bit rate= (baud rate) X (number of bits per signal)

Question 13

what is the relationship between bit rate and bandwidth

Answer 13

bit rate is directly proportionate to bandwidth

Question 14

what is client server networking

Answer 14

one or more computers are connected to a powerful computer called a server

clients have to request access and services from the server

Question 15

pros of client server

Answer 15

pros: better security as all files are stored in a central location and access rights are managed by the server
back ups and updates are done centrally so individual users dont have to do this manually and all devices can be simultaneously updated and backed up
data and other resources can be shared

Question 16

cons of client server

Answer 16

cons: expensive to install and manage

professional staff required to maintain servers a d run the network if the servers go down the network goes down

Question 17

what is a peer to peer network

Answer 17

all computers have equal status so they are all clients and servers

Question 18

pros of peer to peer networking

Answer 18

cheap to set up
users share resource s
easy to maintain
if one computer goes down only the data stored on that computer is effected

Question 19

cons of peer to peer networking

Answer 19

Widley used for privacy of content as files that are illegally downloaded are impossible to trace