cyber security

• Network security


  The range of measures that can be taken to protect network data from accidental or malicious damage
• Encryption


  Conversion of data, using an algorithm, into cyphertext that cannot be understood by people without the decryption key
• Compression


  The process of reducing file size to allow more data to be stored on the disk and increase transfer speeds
• Backup


  A copy of data that can be used if the original data is lost
• Archiving


  The process of storing data that is not in current use for security, legal or historical reasons
• Cybersecurity


  The range of measures that can be taken to protect computer systems from cyberattack
• Cyberattack


  An attempt to expose, alter, disable, destroy, steal or gain unauthorized access to data on a computer system or smart device
• Malware


  MALicious softWARE; the term used for any kind of computer software written to enable a cyberattack
• Vulnerabilities


  Software security flaws or holes that are fixed via the release of patches
• Cookies


  Data downloaded from a website that allows the website to identify the computer in future
• Network security


  • Limiting levels of access
  • Using strong passwords
  • Encryption
• Encryption/decryption example using the XOR logical operator


  1. Original Data

  2. Cyphertext

  3. Key

  4. XOR
• Network policies


  1. Acceptable use policies

  2. Backup policy

  3. Archiving

  4. Disaster Recovery Plan
• Lossless compression


  Uses an algorithm that compresses data into a form that may be decompressed without any loss of data
• Lossy compression


  Compressing file size by discarding some of the data
• Compression ratio


  Original file size / Compressed file size
• Lossy compression is used to compress multimedia data, such as images, sound and video, for internet streaming
• Cybersecurity


  • Install anti-virus software
  • Use a firewall
  • Keep the operating system up to date
  • Use the latest version of browsers
  • Look out for phishing emails
• Footprinting and ethical hacking


  Strategies for penetration testing (targeted, internal, external and blind testing)
• Secure by design


  An approach to make software systems as free of vulnerabilities as possible through continuous testing and adherence to best programming practices