LO6

• Logical protection

  Using digital methods of security to protect computer systems and data
• Usernames and passwords


  • Usernames must be matched with a secure password to minimise the chances of unauthorised users accessing a system
  • Passwords should contain a mix of uppercase and lowercase letters, punctuation and numbers
  • Passwords should be of a substantial length (at least 8 characters) and should be regularly changed
• Anti-virus software

  • Scans a system and removes viruses
  • If left to infect a system a virus could delete data or permit access to unauthorised users
• Anti-spyware software

  Removes spyware on an infected system so hackers cannot view personal data or monitor users
• Firewall

  • Prevents unauthorised access to or from a network
  • Filters data packets and blocks anything that is identified as harmful to the computer system or network
  • Can also be used to block access to specific websites and programs
• Firewall types

  • Physical device connected to the network
  • Software installed on a computer system
• Encryption

  • Conversion of data (plaintext) into an unreadable format (ciphertext) so it cannot be understood if intercepted
  • Encrypted data can only be understood by an authorised system with a decryption key
• Types of encryption

  • Encryption at rest (data encrypted while stored on a system or storage drive)
  • Encryption in transit (data secured as it being transferred between systems on a network)
• Tiered levels of access

  • Grants different types of permission to certain users
  • Ensures that only authorised people can access and change certain files
• Levels of file access

  • No access
  • Read-only (allows a user to view but not edit)
  • Read/write (allows a user to view and edit)
• Obfuscation

  • Data is deliberately changed to be unreadable to humans but still understandable by computers
  • Program code might be obfuscated to stop rival programmers from viewing and stealing it if they were able to access it
• Specialist software can be used to obfuscate data and convert it back into a human-readable format