Mich 1 Flashcards
What are some advantages to connecting computers in a network?
(4 advantages)
- sharing of files/data
- sharing of peripherals (e.g. printer)
- improved communication (e.g. email, video conferencing)
- centralised management of computers (e.g. installing software, monitoring)
What is the topology of a
Local Area Network?
bus, star, mesh
What is the topology of a
Wide Area Network?
partial mesh
What type of addressing does a
LAN use?
MAC addressing
What type of addressing does a
WAN use?
IP addressing
What hardware forwards packets in a
LAN?
switches
What hardware forwards packets in a
WAN?
routers
Why is IPv6 needed?
(instead of just IPv4)
It allows for many more addresses
(IPv4 only allows 2^32 addresses which is not enough)
What things are found in the
header of a network packet?
(6 things)
- source/ sender IP address
- destination IP address
- packet/sequence number
- checksum (for error checking)
- packet/data size
- protocol and version
Define
speed.
the data transmission rate achieved in bits per second
this is affected by the latency and the bandwidth
Define
range.
the maximum distance a signal can travel before becoming disrupted
(measured in metres)
Define
latency.
the time delay between the moment the data is transmitted and the moment that it is received
(measured in milliseconds - higher is worse)
this can be visualised as the speed limit on the road
Define
bandwidth.
the maximum amount of data that can be transmitted in one second
(measured in bits per second bps)
this can be visualised as the number of lanes on a motorway
How would you calculate
file size?
size (bits) = time (seconds) x bandwidth (bps)
What are the powers of bytes in ascending order?
Burger - byte (B)
King - kibibyte (KiB) or kilobyte (KB)
Made - mebibibyte (MiB) or megabyte (MB)
Great - gibibyte (GiB) or gigabyte (GB)
Toast - tebibyte (TiB) or terabyte (TiB)
Previously - pebibyte (PiB) or petabyte (PB
but - bit (b)
now? - nibble (N)
Define
protocol.
a set of rules that allows devices to communicate
Define
amplitude.
(relating to sound waves)
the extent to which air particles are displaced
this sound amplitude is experienced as the loudness of sound
Define
bit depth.
(as relating to sound representation)
the number of bits stored per sample
the higher the number of bits, the greater the quality of the sound, and the larger the file size
Define
sample interval.
the amount of time which passes between capturing each sample
Define
sample rate.
the number of samples stored per second
the higher the number of samples per second, the higher the quality of the sound, and the larger the file size
What does a larger amplitude mean for a sound wave?
louder sound
What does a higher frequency mean for a sound wave?
higher pitch
What does a microphone do?
converts the continuous changes in air pressure caused by sound waves into an electrical signal
since computers are digital devices, they can only handle sound if it is converted from a continuously changing signal into a sequence of binary values
What does the process of analogue to digital conversion (ADC) involve?
a series of sound ‘snapshots’ are taken and represented as binary data
these are called samples and the process of taking them is called sampling
What bit depth is used for CD recordings?
16
How would you calculate a sound file size?
file size (bits) = sample rate x bit depth x duration (seconds)
What is FLAC used for and what type of compression is it?
sound
lossless
What is JPEG used for and what type of compression is it?
image
lossy
What is MP3 used for and what type of compression is it?
sound
lossy
What is WAV used for and what type of compression is it?
sound
uncompressed
What is ZIP used for and what type of compression is it?
file archives
lossless
What is png used for and what type of compression is it?
image
lossless
What is MP4 used for and what type of compression is it?
video
lossy
What is BMP used for and what type of compression is it?
image
uncompressed
What does
HTTP stand for?
Hyper Text Transfer Protocol
What does
HTTPS stand for?
Hyper Text Transfer Protocol Secure
What does
FTP stand for?
File Transfer Protocol
What does
SMTP stand for?
Simple Mail Transfer Protocol
What does
IMAP stand for?
Internet Mail Access Protocol
What does
POP3 stand for?
Post Office Protocol
What is HTTP used for?
requests and responses between web browser and web servers
What is HTTPS used for?
encryption communication between browser and web server
What is FTP used for?
sending and receiving files over the internet
What SMTP is used for?
sending emails
What is IMAP used for?
reading/receiving emails
leaves the email on the mail server (often used for web-based email)
What POP3 is used for?
reading/receiving emails
deletes the email off the mail server
