When using cryptography, organizations should consider roles and responsibilities for key management. Cryptographic controls are only effective when keys are properly generated, stored, distributed, rotated, backed up, revoked, destroyed, and protected from unauthorized access. Weak key management can defeat strong algorithms because compromise of the key can expose encrypted information or allow unauthorized signing, decryption, or impersonation. ISO/IEC 27002 Control 8.24, Use of cryptography, guides organizations to define rules for effective cryptographic use, including protection of confidentiality, authenticity, integrity, and non-repudiation where relevant. Key management responsibilities must be assigned clearly so that ownership, custody, approval, recovery, and emergency access are controlled. Option B relates to project security management, not cryptographic implementation specifically. Option C relates to network security and filtering, not cryptographic key governance. Cryptography requires policy decisions about algorithms, key lengths, certificate management, lifecycle handling, legal restrictions, and separation of duties. The exam’s correct answer is therefore option A because key management is a central technical and governance constraint of cryptographic protection. References/Chapters: ISO/IEC 27002:2022, Control 8.24 Use of cryptography; Control 5.15 Access control; Control 5.17 Authentication information.
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