Which Masking Method? — TechKnowSurge

About this interactive

The Data Masking and Obfuscation lesson treats the two terms as one: modifying sensitive data so it has little or no value to an intruder but still serves the company. It is how de-identification (removing what identifies a person) and anonymization (going further, so nothing left can lead back to them) are carried out. Substitution: replace each value with one from outside the data, such as a name picked from a list of thousands. Shuffling: move the real values around among the records, so a name no longer sits beside its own birth date and address. Number and date variance: shift each number or date by a random amount, such as a birth date moved up to ten years either way, or an address number moved within ten percent. Hashing: replace a value with its hash. The lesson uses it for passwords, but avoids it for test data because the result looks nothing like real data. Encryption also obscures data, but it can be decrypted, so it is a poor fit for de-identification. Nulling: delete the value or leave the field empty. The data stays safe, but may not work well as test data. Masking out: show only part of the value, such as the last four digits of a card or a Social Security number. A quick test for each card: where did the new value come from, and how much of the old one is left?

What you'll learn

Identify which data masking or obfuscation method changed a value: substitution, shuffling, number or date variance, hashing, nulling or masking out
Tell substitution, which brings in values from outside the data set, from shuffling, which moves the real values to other records, and from variance, which shifts each value by a random amount

Aligned to

CompTIA Security+

3.3 Compare and contrast concepts and strategies to protect data.

1.4 Explain the importance of using appropriate cryptographic solutions.

NIST 800-53

SI-19 De-Identification

ISC2 CISSP

2.4 Manage data lifecycle

Key terms

Data Obfuscation: The practice of making data or code deliberately unclear or unintelligible to prevent unauthorized understanding or use.
Shuffling: A data masking technique that rearranges existing data values across records so that values no longer correspond to the correct individual.
Nulling: A data obfuscation technique that deletes or replaces sensitive field values with null, removing the data entirely from the dataset.
Masking: A data obfuscation technique that hides portions of sensitive data, such as displaying only the last four digits of a credit card number.
Hash Function: A mathematical algorithm that converts input data of any size into a fixed-size output value used to verify data integrity.
Anonymization: An advanced form of deidentification that removes PII and also eliminates any combination of remaining data that could be reverse-engineered to identify a person.

Topics

Data Masking Obfuscation Interactive Categorize

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