Spring Boot Field-Level Encryption: How AES-256-GCM Protects Sensitive Data

The article explains why insurance applications storing driver details such as date of birth and license numbers need protection beyond database access controls, since a stolen database dump could expose them. It argues that encryption rather than hashing is required when the original values must later be recovered for tasks like age calculation or underwriting, while passwords should use a dedicated hashing algorithm like Argon2id. It describes AES-256-GCM as a symmetric, authenticated encryption method that provides both confidentiality and tamper detection. The walkthrough covers how a random 12-byte initialization vector is generated per encryption so identical values produce different ciphertext, and how the algorithm outputs ciphertext plus an authentication tag. The piece indicates it will go on to show how to implement this field-level encryption in a Spring Boot application.