What does 3.1 require?

Three sanitization methods are defined: clear, purge and destroy, each with one or more technology-specific techniques, which are either logical (software or commands over an interface that replace, eliminate or block access to data, intended to leave the ISM usable) or physical (external measures that eliminate the data or the ISM, usually leaving it unusable). Techniques must be refreshed regularly as storage technology evolves, so the current edition of standards such as IEEE 2883 is consulted. Techniques must be matched carefully to the ISM, because host interfaces can look alike across quite different underlying media.

NIST SP 800-88 Rev 2 3.1: Use the three methods (clear...

Other controls in Section 3: sanitization methods (clear, purge, destroy) and cryptographic erase – NIST SP 800-88 Rev 2

3 Categorise the information, assess the media and the confidentiality risk, decide the media's future, then choose and justify the sanitization method
3.1.1 Clear: logical techniques over the user interface against simple recovery; not for hard copy; avoid multi-pass overwriting on overprovisioned flash; use dedicated sanitize commands or factory reset where rewriting is unsupported
3.1.2 Purge: physical or logical techniques that defeat laboratory recovery while keeping the ISM reusable; prefer purge to clear; choose techniques from IEEE 2883; cryptographic erase may be the only purge option for virtual storage; degauss only magnetic media with a matched degausser
3.1.3 Destroy: render recovery infeasible and the media unusable by disintegrating, incinerating, melting, pulverizing or shredding; partial damage does not count; avoid shred and pulverize for dense media above the lowest category
3.2 Cryptographic erase as a purge technique: sanitize or block access to the keys that encrypt the data; federal agencies use modules validated to the current FIPS 140 standard
3.2.1 Strength of cryptography for CE: at least 128-bit security strength, entropy at least equal to the key length, and the Table 1 requirements on key generation, media encryption, key wrapping and key derivation
3.2.2 Applicability of CE: only where no sensitive plaintext was ever stored since the last sanitization, with caution for long-lived sensitivity, and never trusted where keys were backed up or escrowed without control
3.2.3 Sanitization of keys: zeroize every copy of the target cryptographic keys and all keys beneath them, eliminate unwrapped copies in volatile memory or registers, and consider external key recovery paths

Query this from an agent

The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.

MCP endpoint All NIST SP 800-88 Rev 2 controls