A data breach is not just a technical incident — it is a business event. Average cost: €4.45M (IBM 2024), plus indirect costs: client loss, reputational damage, insurance premium increases. GDPR requires notifying regulators within 72 hours. Absence of appropriate technical measures is consistently held against organisations.
Data Protection8 April 2026·7 min
Sensitive Data Protection: Encryption, Access Control and GDPR Compliance
Protecting sensitive data means guaranteeing confidentiality, integrity and availability — the CIA triad. This involves encrypting data at rest and in transit, rigorous access management, data minimisation and documented incident response. Under GDPR, fines can reach 4% of global revenue, making data protection both a legal requirement and a trust imperative.
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Why data protection is a strategic priority
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Encryption: the foundation of data protection
At rest (AES-256): all databases, storage volumes and backups containing sensitive data.
In transit (TLS 1.3): all service-to-service and user communications. Disable TLS 1.0/1.1. Enable HSTS.
Key management (PKI): regular rotation, separate key storage, HSM for critical keys. Our data encryption approach covers everything from flux auditing to implementation.
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Access management: least privilege principle
80% of breaches involve accounts with excessive rights. Least privilege: every user, service and process accesses only what is strictly necessary. In practice: quarterly access reviews, automatic deactivation of inactive accounts, MFA on all sensitive access, dev/prod environment separation, logging all critical data access.
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Data classification and minimisation
Classification identifies sensitivity levels (public, internal, confidential, secret) and adapts protection measures accordingly. Minimisation — a fundamental GDPR principle — means collecting only what is strictly necessary. Each piece of data collected is an additional risk.
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Common mistakes
Encrypting data but leaving backups in plaintext. Using obsolete algorithms (MD5, SHA1, DES). Storing encryption keys alongside encrypted data. Not testing backup restoration. Sensitive data in dev/test environments. No access logging for critical data.
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Use cases
Medical practice: AES-256 on patient records, TLS 1.3, mandatory MFA.
HR data: isolated environment, DRH-only access, 1-year access logs.
E-commerce payments: card tokenisation, PCI-DSS, end-to-end encryption. Complement with annual cybersecurity audit and team training.
Frequently Asked Questions
What is AES-256 encryption?
The standard symmetric encryption algorithm for data at rest, using 256-bit keys. Considered unbreakable with current and near-term quantum technology.
What is the difference between encryption and hashing?
Encryption is reversible (decryptable with the key). Hashing is irreversible, used for integrity verification or password storage.
Does GDPR mandate encryption?
GDPR does not specify algorithms but requires 'appropriate technical measures'. Encryption is consistently cited as a reference measure by EU data protection authorities.
What to do in case of a data breach?
Notify the data protection authority within 72 hours if personal data is involved. Preserve evidence. Activate your incident response plan.
In summary
Sensitive data protection is not a one-time project — it is a continuous discipline. Encryption, access management and data minimisation form a technical foundation that any organisation can implement progressively and proportionately.
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