6.1 Data Security

# Data Privacy
- privacy prevents unauthorised access
## Why need to protect both data and system
- Data needs protecting from someone amending / deleting or taking it
- Computer system need protecting to stop people for example, installing malware or damaging the system
# Data Security
- Security prevents against loss
## Security measures designed to protect computer systems
#### User accounts
#### Passwords

### Authentication techniques
#### Digital signatures
##### Explain how a digital signature is used to authenticate a digital document during transmission over a network.
- The sender hashes the document to produce a digest
- The sender encrypts the digest to create the digital signature
- The message and the signature are sent to the receiver
- The receiver decrypts the signature to reproduce the digest
- The receiver uses the same hashing algorithm on the document received to produce a second digest
- The receiver compares this digest with the one from the digital signature
- If both of the receiver's digests are the same the document is authentic
##### How a digital signature ensures the email is authentic
- message put through hashing algorithm to produce a digest
- Digest encrypted with sender's private key to create the digital signature
- the digital signature can only be decrypted with matching sender's public key
#### Biometrics
#### Firewall
- monitors incoming and outgoing packets / traffic
- checks against an allow list / deny list of IP addresses
- blocks transmissions that do not meet criteria.
#### Anti-virus software
- scans the computer for viruses and checks against a stored database of viruses, that needs to be updated regularly and then deletes / quarantines them
- compares downloaded files to a database of known viruses and prevents the download continuing
#### Anti-spyware
- scans the computer for spyware and checks against a stored database of viruses, that needs to be updated regularly and then deletes / quarantines them
- compares downloaded files to a database of known spyware and prevents the download continuing.
#### Anti-malware
- scans the computer for viruses and checks against a stored database of viruses, that needs to be updated regularly and then deletes / quarantines them
- compares downloaded files to a database of known viruses and prevents the download continuing
#### Encryption
## Security methods designed to protect the security of data
### Encryption
- Data is turned into cipher text // Data is encoded
- Used so that it cannot be understood if intercepted without the decryption key
## Threats to computer and data security posed by networks and the internet
### Malware
- Malicious software that replicates and can delete/damage the examination papers
- **Protect against threat:** install and run anti-malware
### Hacker/unauthorised access
- Unauthorised access to the computer with malicious intent: delete/damage the examination papers
- **Protect against threat:** Use a firewall // strong passwords
### Spyware
- Records keystrokes and sends the data gathered about the examination papers to a third party
- Software installed on the computer without the teacher's knowledge
- Malicious software
- Run in the background
- **Protect against threat:** Use a firewall / install and run anti-spyware / use a virtual (onscreen) keyboard
### Virus
- Damage computer data
- Replicates itself
- Software installed on the computer without the person's knowledge
- Malicious software
- Run in the background
- **Protect against threat:** Anti-virus / Firewall / Anti-malware
### Pharming
- redirects a user to a false website
- Malicious code installed on a user's hard drive
- this code redirects the user to a fake website without their knowledge
- This is done to obtain personal or financial data
### Phishing:
- Creator of code sends out a legitimate looking email in the hope of gathering personal and financial information from the recipient. 
- It requires the user to click on the link in the email or attachment.