Computer Science Paper 2

Recording a signal at regular intervals

Num of samples obtained per second

Better quality but bigger file size

How many bits are available for each sample - bit depth

Sample frequency x bit depth

sample frequency x bit depth x time

Some data is removed from the file

Rearranged data to make it more efficient

4y3b4p2r

Reverses input

Returns true if either / both input are true

Returns true if both inputs are true

Returns true if either (not both) are true

Used to carry out tasks on a computer e.g web browsers

Peforms tasks need to operate the hardware e.g operating system, utility software

Manages computer system e.g linux

Binary

Communicates with computer

Like Python

programmer understands vs computer understands

Converts code from one language to another - all code needs to be translated to machine code

Converts assembly to machine code

Converts high level to machine code translates the whole block

Converts high level to machine code translates line by line and slower than compiler

Perform arithmetic and logic operations

Coordinates the CPU

Quick small stores of data in cpu

Provide signals to synchronise internal components

Volatile memory that can be read/write to

Non volatile memory that can only be read to

Fast but small memory that stores frequently used data

Processing units

Binary data

Light is shined and light that hits a land reflects differently to when it hits a pit. E.g pits can be read as 0 and lands as 1. Data is written with a laser burning the pits into the disk

Small capacity

Reliable

Very portable

Parts of the surface are either magnetised (1) or demagnetised (0) by the electromagnets in the head.

Can be noisy and generate heat

Large capacity

Cheap

Form of flash memory

Expensive

Silent

Reliable as non-mechanical

A special purpose computer

Connection between devices to share resources

Set of rules for communication

HTTP/S, FTP, SMTP, IMAP

TCP, UDP

IP

Ethernet, Wifi

Where the network applications operate

Sets up communication between two hosts

Handles and routes data

Where hardware operates

Insert themselves in normal programs

Generates unwanted adverts

Disguised as a desirable software but there is malware hidden within it

Collects data about the user

Inventing a scenario to gain a victim trust

Obtaining private info through a fake link often pretending to be something your not

Cyberattack where websites traffic is redirected to a fake site

Viewing private info over the person shoulder

Monitor network traffic and filter packets based on rules

Attempting to gain access with some knowledge and basic credentials - simulating an inside attack

Attempting to gain access with no knowledge - simulating an outside attack

used for accessing webpages from a server and uses encryption to secure data

handling out bound email vs handling in bound email

Similarity; exists to deal with connection between devices

Differences; TCP - two way connection splits and slower and more reliable

UDP - sends data one way and faster and less reliable

Enables communication over the internet

too much energy use and finite resource use

changing the job market and social media also makes it easier to spread abuse and hold politicians accountable

the right to privacy conflicting with the government ensuring public safety e. g FBI asking apple to hack into a phone

Blackmail , stealing of financial info