Documenting how to handle confidential criteria

• Availability, integrity and confidentiality are provided at the necessary levels for all identified assets
• Return on investment by implementing controls where they are needed the most
• Map data protection levels with organizational needs
• Mitigate threats of unauthorized access and disclosure
• Comply with legal and regulation requirements

The steps to develop and roll out a data classification program are:

1. Compile an inventory of all information assets
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3. Define levels of protection for information assets
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5. Define a classification criteria
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7. Develop information classification policy
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9. Define information handling and labeling procedures
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11. Assign responsibility for classification to the owner of information
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13. Assign a security classification to all information assets
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15. Classify information according to sensitivity and how much protection is required
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17. Apply the classification system to documents, records, data files, and disks.
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19. Develop information handling procedures for each class of information
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21. Develop information labeling procedures for each class of information
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23. Integrate into security awareness and training programs
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You should have a data classification policy that covers the following:

• Information as assets of individual business units
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• Declare business unit managers as information owners
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• Declare IT as data custodians
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• Classification scheme
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• Definitions for each classification
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• Criteria for each classification
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• Roles and responsibilities of classification
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Your written procedures and guidelines should address the following;

• How to classify information
• How to change classification level if needed
• How to communicate classification change to IT
• Periodic review of
  • Current classification levels and mapping to business needs
  • Current access rights and privileges
  • Protection levels that current controls are using

The NIST 800-60 document may be too "DoD centric" and an overkill for your needs, but this document has the necessary guidelines to develop and maintain a structured data classification program.

Sun provides a more digestible and understandable approach, which can be found at http://www.sun.com/blueprints/tools/samp_sec_pol.pdf

Lastly, this link provides detailed guidelines for how to treat different types of data.