Security, privacy, data integrity and encryption

Learning objectives

Distinguish data security, data privacy and data integrity, and explain how a system can protect one of the three well while protecting another badly

Describe the threats posed by malware, phishing, pharming, hacking and accidental damage, and explain how firewalls, authentication, access rights, anti-malware software and a backup routine each reduce the risk

Describe range, format, length, presence, existence and check digit validation, and verification by double entry and by visual check, stating what each method can and cannot detect

Explain how a parity check and a checksum detect errors introduced during transmission, calculate a parity bit and a checksum for given data, and explain why a parity check can miss two errors in the same byte

(A Level) Compare symmetric and asymmetric encryption, explain the roles of the public key and the private key, and explain how asymmetric encryption solves the problem of distributing a shared secret key

(A Level) Explain how a digital signature and a digital certificate authenticate a sender, describing the use of a hashing algorithm and of a certificate authority, and outline what SSL and TLS do when a secure session begins

Describe a limit check, and use a parity block check to locate and correct a single-bit error in a transmitted block

(A Level) Explain what quantum cryptography is for, and weigh its advantages against its limitations