Data breaches make headlines almost weekly, yet many organisations still treat encryption as an afterthought rather than a foundational security requirement. Sensitive customer records, financial data, and intellectual property deserve protection that persists even when other defences fail. Encryption provides that last line of defence, rendering stolen data useless to attackers who lack the decryption keys.
Understanding the difference between encryption at rest and encryption in transit is essential. Data at rest refers to information stored on drives, databases, and backup media. Data in transit covers information moving between systems, whether across the internet or between servers within the same data centre. Both states require protection, and the approaches differ.
For data at rest, modern standards point toward AES-256 as the gold standard for symmetric encryption. This algorithm withstands all known attack methods and remains computationally practical for real-world workloads. Organisations should avoid deprecated algorithms like DES or RC4, which offer inadequate protection against current threats.
Key management separates effective encryption from security theatre. Storing encryption keys on the same server as the encrypted data is equivalent to locking a door and leaving the key under the doormat. Dedicated key management systems, hardware security modules, and proper key rotation policies ensure that compromised storage does not automatically mean compromised data.
Cloud environments introduce additional encryption considerations. Major providers offer built-in encryption options, but organisations must understand who controls the keys. Provider-managed keys simplify operations but grant the cloud provider theoretical access to your data. Customer-managed keys offer greater control at the cost of increased operational complexity. Conducting Azure penetration testing or equivalent assessments for your cloud environment verifies that encryption configurations actually protect your data as intended.
Expert Commentary
William Fieldhouse | Director of Aardwolf Security Ltd
“Encryption remains one of the most powerful tools available for data protection, but only when implemented correctly. We routinely find organisations using outdated algorithms, storing encryption keys alongside the data they protect, or failing to encrypt data in transit between internal services. These mistakes turn encryption from a safeguard into a false sense of security.”
Transport Layer Security protects data in transit across networks. Organisations should enforce TLS 1.2 or higher for all communications, disable older protocol versions, and use strong cipher suites. Certificate management processes must prevent expired or misconfigured certificates from creating gaps in transit encryption.
Database encryption requires careful planning. Column-level encryption protects specific sensitive fields while allowing the database to operate efficiently on non-sensitive data. Full database encryption simplifies management but can impact query performance. The right choice depends on your data sensitivity requirements and performance constraints.
End-to-end encryption protects data throughout its entire journey, from source to destination. This approach prevents intermediary systems, including your own infrastructure, from accessing plaintext data. For particularly sensitive communications or data transfers, end-to-end encryption eliminates trust dependencies on every system along the path.
Engaging the best penetration testing company available to test your encryption implementation reveals weaknesses that internal reviews often miss. Professional testers look for deprecated protocols, weak configurations, exposed keys, and implementation flaws that undermine your encryption strategy.
Encryption is not a set-and-forget measure. Algorithms weaken over time as computing power advances and new attacks emerge. Organisations need ongoing reviews of their encryption standards, regular key rotation, and migration plans for transitioning to stronger algorithms as current ones approach the end of their effective lifespan.
