Exam CAS-005 topic 1 question 60 discussion

Tokenization through a Hardware Security Module (HSM) is the most appropriate solution for securely storing and using previously saved payment methods. It allows sensitive payment data (like credit card numbers) to be replaced with non-sensitive tokens that can be used in place of the actual data to perform recurring transactions. An HSM provides secure, tamper-resistant cryptographic operations, ensuring that the real cardholder data never needs to be stored in the application, reducing PCI DSS compliance scope. Why not the others? B. Self-encrypting disks with field-level encryption: Good for protecting data at rest but doesn't solve the problem of using payment data securely for recurring transactions. C. NX/XN Implementation: Related to preventing execution of code in non-executable memory regions — irrelevant to payment data storage/usage. D. Token-based access for application users: Refers to user authentication/authorization, not payment method storage. E. Address Space Layout Randomization (ASLR): A memory protection mechanism — not applicable to secure payment data handling.