📖 What is Data Custodian?

A Data Custodian is the individual or entity responsible for the technical implementation of security controls to protect data. They handle backups, integrity checks, and access permissions as directed by the Data Owner to ensure the data remains available and secure.

🥋 Sensei Says:

"Think of the Custodian as the 'doer.' They do not decide who gets access; they execute the technical configuration based on the Owner's policy."

📚 Certification: Certified Information Systems Security Professional (CISSP)

🔑 What are the Key Concepts of Data Custodian?

  • Responsible for the technical implementation of security controls, such as configuring encryption, managing access control lists, and ensuring data is stored securely.
  • Executes operational tasks of data maintenance, including performing regular backups, managing archives, and conducting integrity checks to prevent data corruption.
  • Operates under the direction of the Data Owner, translating high-level security policies and classification levels into specific technical configurations and system settings.
  • Ensures data availability and reliability by implementing disaster recovery procedures and maintaining the technical infrastructure where the data resides.

🎯 How does Data Custodian appear on the CISSP Exam?

You may be asked to identify the role responsible for performing a daily backup of a database after the Data Owner has defined the required recovery point objective.

A scenario might describe a system administrator configuring firewall rules to protect a sensitive dataset; you must identify this individual as acting in the role of the Data Custodian.

Expect questions that test your ability to distinguish between the person who determines the data's classification (Owner) and the person who implements the technical protections (Custodian).

❓ Frequently Asked Questions

Can a Data Custodian change the classification level of a dataset if they find it is more sensitive than previously thought?

No. The Data Custodian implements the controls, but only the Data Owner has the authority to determine or change the classification level of the data based on business value.


What is the primary difference between a Data Custodian and a System Administrator in the context of the CISSP exam?

While often the same person in practice, the 'Custodian' role specifically refers to the responsibility for the data's integrity and availability, whereas a System Administrator manages the overall hardware and OS.

Related Terms from Certified Information Systems Security Professional

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