HTTP - hypertext transfer protocol - correct answera set of rules which must be followed when
transferring files across the internet
URL - uniform resource locator - correct answerused to find/identify a webpage on the internet
1. webserver name 2. file name 3. protocol
web browser - correct answersoftware that allows a user to display a webpage on their screen -
they interpret html code and show the result
actuator - correct answerused in many control operations involving sensors and ADC/DACs.
Electromagnetic device eg. motor that outputs result of sensor operation
loudspeaker - correct answeroutput device that produces sound using voltages at different
levels which vibrate a cone in speaker housing
LED - correct answerUsed for backlighting a monitor/tv - they are thin, produce a white light,
and do not require much power
CCFL - correct answerOld technology used for backlighting - took time to warm up, and
produced yellow-ish lighting + required a lot of power
volatile - correct answermemory that loses its contents when the power is off eg. main memory
non-volatile - correct answermemory that doesn't lose its contents when the power is off e.g.
hard disk
off-line storage - correct answerstorage that can be physically moved away from a device and
stored somewhere else e.g. CD, USB stick, DVD
SRAM - correct answertype of RAM that has 'flip flops' to hold each bit of memory. Does not
need constant refreshing.
magnetic media - correct answersecondary storage with mechanical parts which move over the
surface to read and write data magnetically e.g. a hard disk, tape or floppy disk
program - correct answerour way of telling a computer what to do, how to do it, and when to
do it
assembly language - correct answercode that is specific to a particular hardware, but needs to
be translated into machine code before it can run
machine code - correct answerthe binary code that is specific to a machine and does not need
translating in order to run
translator - correct answerprogram that changes higher level language into machine code
compiler - correct answerthis translates HLL into machine code. Once it has done this, the
program can be used multiple times without translating it again
,UPS - correct answeruninterruptable power supply
cracking - correct answerediting source code with malicious intent
firewall - correct answerthis examines traffic between a user's computer and the internet by
checking what is/isn't allowed and blocking traffic that does not meet certain criteria
proxy server - correct answerthis filters web traffic, keeps the IP address secret, and, using a
cache, speeds up access to websites that have been visited before
TLS - Transport Layer Security - correct answerthis is a form of secure data transmission made
up of 2 layers: the record protocol, and the handshaking protocol. It is very secure and fairly
new, and can make use of session caching, which improves performance. It involves many
complicated encryption algorithms. prevents third party hacking into communication between
web server and the user's computer.
session caching - correct answerthis is used in TLS to avoid using too much computer time; TLS
is able to attempt to resume an existing session, which increases speed.
Denial of Service (DoS) attack - correct answerattempting to prevent a user from accessing part
of a network (usually the server); this is usually temporary, but may be very damaging, or a big
security breach. overloads web traffic by sending thousands of requests.
free software - correct answersoftware that is free to run, copy, change or adapt, and share
with friends, family or colleagues.
CSS - correct answerCascading Style Sheet. Controls presentation of page. Enable multiple
pages or elements on a page to be changed in one go.
Gigabyte (GB) - correct answer1024 megabytes. 2 to the power of 30 bytes.
HTML - correct answerHyperText Mark-up Language. Used to write and develop webpages to
present text. Uses tags.
Terabyte (TB) - correct answer1024 gigabytes. 2 to the power of 40 bytes.
Lossless image compression - correct answerFind groups of repeating data. Records the data
once and the number of times it was repeated.
Lossless text compression - correct answerFinds patterns in original text. Encodes each pattern
in a dictionary
PNG - correct answerLossless picture file format that uses alpha channel to keep transparent
backgrounds.
MIDI - correct answerA set of instructions for digital instruments to play synthesised sounds.
Musical Instrument Digital Interface.
,.WAV - correct answeruncompressed music files
.FLAC - correct answerlossless compressed music files
Parity bit - correct answerSet to 1 or 0. Sent with a byte of data to make the total number of 1s
odd or even for each byte.
1KB (kilobyte) - correct answer1,024 bytes (2¹⁰ bits)
1MB (megabyte) - correct answer(2²⁰ bits)
1GB (gigabyte) - correct answer(2³⁰ bits)
1TB (terabyte) - correct answer(2⁴⁰ bits)
1PB (petabyte) - correct answer(2⁵⁰ bits)
A - correct answer10
B - correct answer11
C - correct answer12
D - correct answer13
E - correct answer14
F - correct answer15
Simplex - correct answerData sent in 1 direction only
Asynchronous - correct answerAgreed bit pattern with control bits
Parity Check - correct answerUses parity bits. Odd Parity / Even Parity agreed between sender
and receiver. If it is not the agreed number, an error has occurred.
ARQ (Automatic Repeat Request) - correct answerUses acknowledgement and timeout. If
acknowledgement isn't sent back to sender before the timeout occurs, message automatically
resent.
Checksum - correct answerAdditional value sent at the end of a data block. When block is about
to be transmitted, additional value calculated and then transmitted. Value recalculated at the
end to make sure they match. If they don't match, an error has occurred.
Echo Check - correct answerData sent to and from another device twice. Sender compares 2
sets of data, if the sets of data are different, an error has occurred.
Wardriving - correct answerUsing wireless internet connections illegally through a portable
device
, Secure Sockets Layer (SSL) - correct answerWhen a user logs onto a website, it encrypts the
data. Only the user's computer + web server can make sense of what's being said. A green
padlock in the status bar.
Record Protocol - correct answerCan be used with or without encryption
Handshake Protocol - correct answerPermits the website and user to authenticate and make
use of encryption algorithms which only the user and website know.
Encryption - correct answerMakes data meaningless unless recipient has the decryption key
Asymmetric Encryption - correct answerPrivate and public key are both needed. Encryption
keys generated using a hashing algorithm.
Authentication - correct answerUsed to verify data is coming from a trusted source.
MAC address - correct answera number that uniquely identifies a device on the Internet. Often
refers to network card. Rarely changed.
ISP (internet service provider) - correct answercompany charging monthly fee that provides
internet access
IP (internet protocol) address - correct answerassigned by ISP, unique to each internet session
MAC address - correct answernumber which uniquely identifies a device - 1st half =
manufacturer, 2nd = device itself - made up of 6 groups of hex digits
HTML Presentation - correct answerhow the document looks/sounds
HTTPS - correct answera SECURE set of rules which must be followed when transferring files
across the internet
OLED - correct answernew technology used for tv/monitor screens, using a cathode and anode.
Flexible, no backlighting required.
DLP - correct answerlight projector using mirrors to produce 1024 different grey shades. A
bright white light source passed through colour filter allowing 16million colours to be created.
ROM - correct answermemory that is hard coded at time of manufacture. Stores start-up
programs, bios and BOOTSTRAP
secondary memory/storage - correct answerlong-term, non volatile storage media e.g. hard
disk
virtual memory - correct answerpart of the hard disk that is programmed to work as an
extension of main memory
transferring files across the internet
URL - uniform resource locator - correct answerused to find/identify a webpage on the internet
1. webserver name 2. file name 3. protocol
web browser - correct answersoftware that allows a user to display a webpage on their screen -
they interpret html code and show the result
actuator - correct answerused in many control operations involving sensors and ADC/DACs.
Electromagnetic device eg. motor that outputs result of sensor operation
loudspeaker - correct answeroutput device that produces sound using voltages at different
levels which vibrate a cone in speaker housing
LED - correct answerUsed for backlighting a monitor/tv - they are thin, produce a white light,
and do not require much power
CCFL - correct answerOld technology used for backlighting - took time to warm up, and
produced yellow-ish lighting + required a lot of power
volatile - correct answermemory that loses its contents when the power is off eg. main memory
non-volatile - correct answermemory that doesn't lose its contents when the power is off e.g.
hard disk
off-line storage - correct answerstorage that can be physically moved away from a device and
stored somewhere else e.g. CD, USB stick, DVD
SRAM - correct answertype of RAM that has 'flip flops' to hold each bit of memory. Does not
need constant refreshing.
magnetic media - correct answersecondary storage with mechanical parts which move over the
surface to read and write data magnetically e.g. a hard disk, tape or floppy disk
program - correct answerour way of telling a computer what to do, how to do it, and when to
do it
assembly language - correct answercode that is specific to a particular hardware, but needs to
be translated into machine code before it can run
machine code - correct answerthe binary code that is specific to a machine and does not need
translating in order to run
translator - correct answerprogram that changes higher level language into machine code
compiler - correct answerthis translates HLL into machine code. Once it has done this, the
program can be used multiple times without translating it again
,UPS - correct answeruninterruptable power supply
cracking - correct answerediting source code with malicious intent
firewall - correct answerthis examines traffic between a user's computer and the internet by
checking what is/isn't allowed and blocking traffic that does not meet certain criteria
proxy server - correct answerthis filters web traffic, keeps the IP address secret, and, using a
cache, speeds up access to websites that have been visited before
TLS - Transport Layer Security - correct answerthis is a form of secure data transmission made
up of 2 layers: the record protocol, and the handshaking protocol. It is very secure and fairly
new, and can make use of session caching, which improves performance. It involves many
complicated encryption algorithms. prevents third party hacking into communication between
web server and the user's computer.
session caching - correct answerthis is used in TLS to avoid using too much computer time; TLS
is able to attempt to resume an existing session, which increases speed.
Denial of Service (DoS) attack - correct answerattempting to prevent a user from accessing part
of a network (usually the server); this is usually temporary, but may be very damaging, or a big
security breach. overloads web traffic by sending thousands of requests.
free software - correct answersoftware that is free to run, copy, change or adapt, and share
with friends, family or colleagues.
CSS - correct answerCascading Style Sheet. Controls presentation of page. Enable multiple
pages or elements on a page to be changed in one go.
Gigabyte (GB) - correct answer1024 megabytes. 2 to the power of 30 bytes.
HTML - correct answerHyperText Mark-up Language. Used to write and develop webpages to
present text. Uses tags.
Terabyte (TB) - correct answer1024 gigabytes. 2 to the power of 40 bytes.
Lossless image compression - correct answerFind groups of repeating data. Records the data
once and the number of times it was repeated.
Lossless text compression - correct answerFinds patterns in original text. Encodes each pattern
in a dictionary
PNG - correct answerLossless picture file format that uses alpha channel to keep transparent
backgrounds.
MIDI - correct answerA set of instructions for digital instruments to play synthesised sounds.
Musical Instrument Digital Interface.
,.WAV - correct answeruncompressed music files
.FLAC - correct answerlossless compressed music files
Parity bit - correct answerSet to 1 or 0. Sent with a byte of data to make the total number of 1s
odd or even for each byte.
1KB (kilobyte) - correct answer1,024 bytes (2¹⁰ bits)
1MB (megabyte) - correct answer(2²⁰ bits)
1GB (gigabyte) - correct answer(2³⁰ bits)
1TB (terabyte) - correct answer(2⁴⁰ bits)
1PB (petabyte) - correct answer(2⁵⁰ bits)
A - correct answer10
B - correct answer11
C - correct answer12
D - correct answer13
E - correct answer14
F - correct answer15
Simplex - correct answerData sent in 1 direction only
Asynchronous - correct answerAgreed bit pattern with control bits
Parity Check - correct answerUses parity bits. Odd Parity / Even Parity agreed between sender
and receiver. If it is not the agreed number, an error has occurred.
ARQ (Automatic Repeat Request) - correct answerUses acknowledgement and timeout. If
acknowledgement isn't sent back to sender before the timeout occurs, message automatically
resent.
Checksum - correct answerAdditional value sent at the end of a data block. When block is about
to be transmitted, additional value calculated and then transmitted. Value recalculated at the
end to make sure they match. If they don't match, an error has occurred.
Echo Check - correct answerData sent to and from another device twice. Sender compares 2
sets of data, if the sets of data are different, an error has occurred.
Wardriving - correct answerUsing wireless internet connections illegally through a portable
device
, Secure Sockets Layer (SSL) - correct answerWhen a user logs onto a website, it encrypts the
data. Only the user's computer + web server can make sense of what's being said. A green
padlock in the status bar.
Record Protocol - correct answerCan be used with or without encryption
Handshake Protocol - correct answerPermits the website and user to authenticate and make
use of encryption algorithms which only the user and website know.
Encryption - correct answerMakes data meaningless unless recipient has the decryption key
Asymmetric Encryption - correct answerPrivate and public key are both needed. Encryption
keys generated using a hashing algorithm.
Authentication - correct answerUsed to verify data is coming from a trusted source.
MAC address - correct answera number that uniquely identifies a device on the Internet. Often
refers to network card. Rarely changed.
ISP (internet service provider) - correct answercompany charging monthly fee that provides
internet access
IP (internet protocol) address - correct answerassigned by ISP, unique to each internet session
MAC address - correct answernumber which uniquely identifies a device - 1st half =
manufacturer, 2nd = device itself - made up of 6 groups of hex digits
HTML Presentation - correct answerhow the document looks/sounds
HTTPS - correct answera SECURE set of rules which must be followed when transferring files
across the internet
OLED - correct answernew technology used for tv/monitor screens, using a cathode and anode.
Flexible, no backlighting required.
DLP - correct answerlight projector using mirrors to produce 1024 different grey shades. A
bright white light source passed through colour filter allowing 16million colours to be created.
ROM - correct answermemory that is hard coded at time of manufacture. Stores start-up
programs, bios and BOOTSTRAP
secondary memory/storage - correct answerlong-term, non volatile storage media e.g. hard
disk
virtual memory - correct answerpart of the hard disk that is programmed to work as an
extension of main memory
