Security Hardening and Data Protection Questions

Covers principles and practices for protecting sensitive information and strengthening system security across the stack. Topics include authentication and authorization design such as token based authentication and federated identity, role based access control and attribute based access control, and secure session management. Encryption and hashing fundamentals are required: differences between encryption and hashing, symmetric encryption using standards such as Advanced Encryption Standard, asymmetric encryption using algorithms such as Rivest Shamir Adleman, transport layer security protocols for data in transit, and encryption of data at rest. Key management and lifecycle practices are essential, including secure key generation, storage using key management services or hardware security modules, certificate management, secure key rotation, and backup and recovery of cryptographic keys. Secrets management covers secure storage and retrieval of credentials, API keys, and secrets, plus strategies to avoid accidental exposure such as logging redaction and environment separation. Data protection policies and techniques include data classification, minimization, masking, tokenization, retention and deletion policies, and privacy compliance considerations such as General Data Protection Regulation and Payment Card Industry Data Security Standard. Implementation and operational concerns include secure coding and input validation to prevent injection, protection against common cryptographic and implementation flaws, secure random number generation, rate limiting and distributed denial of service mitigation, monitoring and alerting for suspicious activity, incident response planning, and balancing security controls with developer experience and usability.