Unit Overview
Security, privacy and data integrity
CIE A-Level Computer ScienceΒ· 5 min read π n/a
1. Unit at a glance
This unit follows a logical learning arc: you will first learn what can go wrong with system security, then explore technical safeguards to mitigate those risks, before covering organizational policies and ethical considerations related to data protection.
Each sub-topic builds on the previous to give you a complete end-to-end framework for information protection, from threat identification to post-failure recovery.
This unit includes the following sub-topics:
Threats to security
Classifies common internal and external security threats to computer systems and data.
β β β± 7 min
Encryption
Covers symmetric, asymmetric encryption, hashing, and their common use cases for data protection.
β β β β± 10 min
Access control
Explores methods to restrict system access to only authorized authenticated users.
β β β± 6 min
Data integrity
Covers parity checks, checksums, and other methods to detect and prevent data corruption.
β β β β± 8 min
Privacy issues
Discusses ethical, legal, and regulatory requirements for protecting personal user data.
β β β± 7 min
Backup and recovery
Explains backup strategies and disaster recovery plans for data after system failure or breach.
β β β± 6 min
2. Common Pitfalls
Wrong move:
Confusing encryption with hashing
Why:
Many students mix up these two concepts, forgetting their core purposes differ significantly
Correct move:
Encryption is reversible with a key (used to hide data), while hashing is one-way (used to verify data integrity)
Wrong move:
Mixing up data security and data integrity
Why:
These are overlapping but distinct concepts that are often tested separately
Correct move:
Security prevents unauthorized access to data, while integrity prevents unauthorized modification or corruption of data
3. Quick Reference Cheatsheet
Concept | Key Summary |
|---|---|
Threat classification | Categorized as accidental/deliberate, internal/external, malware/social engineering |
Symmetric encryption | Uses one shared secret key for encryption/decryption; fast for large datasets |
Asymmetric encryption | Uses public/private key pair; used for key exchange and digital signatures |
Hashing | One-way function producing a fixed-length digest; used for integrity and password storage |
Data integrity checks | Common methods: parity bits, checksums, CRC, cryptographic hashing |
3-2-1 Backup Rule | 3 copies of data, 2 stored on different media types, 1 copy stored offsite |
What's Next
Ready to start this unit? Begin with the first sub-topic on threats to security, where you will learn to identify and classify different types of risks that can compromise computer systems and data. Once you complete all sub-topics in this unit, you can move on to the next unit on artificial intelligence to continue your CIE A-Level 9618 preparation.