With the rise of the Internet of Things, Big Data and Open Data, data privacy is increasingly important to organizations. Data de-identification is a process to remove identifying information from a data set. This presentation will provide a gentle introduction to data de-identification, anonymization and the reverse process of re-identification.

1. DATA PRIVACY:
ANONYMIZATION & RE-IDENTIFICATION
Mike Nowakowski
@mike_nowakowski
MARCH 2016

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BACKGROUND
➔ Assessment
➔ Treatment
➔ Financing
RISK MANAGEMENT

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DE-IDENTIFICATION
De-identification is a process which removes the
association (personal information) between a
subject (person) and another entity (data set).
WHAT IS DE-IDENTIFICATION?

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DE-IDENTIFICATION
WHAT IS DE-IDENTIFICATION?
RISK TREATMENT
CONTROLS
DE-IDENTIFICATION... ...
... ...

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DE-IDENTIFICATION
EXAMPLE
Name Birth Date Postal Code Ice Cream
Bob Smith Jan 1, 1957 K1A 0B1 Chocolate Chip
Alice Wilson Mar 3, 1963 B1K 1A0 Vanilla
... ... ... ...

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DE-IDENTIFICATION
EXAMPLE
Name Birth Date Postal Code Ice Cream
Bob Smith Jan 1, 1957 K1A 0B1 Chocolate Chip
Alice Wilson Mar 3, 1963 B1K 1A0 Vanilla
... ... ... ...
Direct Identifier

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DE-IDENTIFICATION
EXAMPLE
Name Birth Date Postal Code Ice Cream
Bob Smith Jan 1, 1957 K1A 0B1 Chocolate Chip
Alice Wilson Mar 3, 1963 B1K 1A0 Vanilla
... ... ... ...
Indirect (Quasi) Identifiers

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DE-IDENTIFICATION
EXAMPLE
ID Name Birth Date Postal Code Ice Cream
47562 Bob Smith Jan 1, 1976 K1A 0B1 Chocolate Chip
17236 Alice Wilson Mar 3, 1963 B1K 1A0 Vanilla
... ... ... ...
ID Ice Cream
47562 Chocolate Chip
17236 Vanilla
... ...

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DE-IDENTIFICATION
How about images? video?
CHALLENGES

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DE-IDENTIFICATION
➔ Goals
◆ Reduce Risk
◆ Maximize Data Use
WHY IS IT IMPORTANT?

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DE-IDENTIFICATION
TECHNIQUES
➔ Suppression
➔ Variation / Noise
➔ Swapping
➔ Masking

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RE-IDENTIFICATION
Re-identification is a process to reassociate a
subject to the original entity in order to determine
the identity of the subject.
WHAT IS RE-IDENTIFICATION?

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RE-IDENTIFICATION
EXAMPLE
Name Birth Date Postal Code Ice Cream
Bob Smith Jan 1, 1957 K1A 0B1 Chocolate Chip
Alice Wilson Mar 3, 1963 B1K 1A0 Vanilla
... ... ... ...

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RE-IDENTIFICATION
LINKAGE
Birth Date
Postal Code
...
Ice Cream
Name
Telephone
...
Secondary
Source

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RE-IDENTIFICATION
➔ Pattern
◆ Account Numbers
◆ Licence Plates
◆ ...
BRUTE FORCE

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RE-IDENTIFICATION
➔ 1997 - Governor's medical records
➔ 2006 - AOL Search Data
➔ 2014 - New York City Taxi
HISTORICAL EVENTS

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ANONYMIZATION
Anonymization is a process which is irreversible and
inhibits the reassociation of the subject to the
original entity.
WHAT IS ANONYMIZATION?

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ANONYMIZATION
EXAMPLE
ID Name Birth Date Postal Code
47562 Bob Smith Jan 1, 1957 K1A 0B1
17236 Alice Wilson Mar 3, 1963 B1K 1A0
ID Ice Cream
47562 Chocolate Chip
17236 Vanilla

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RISK MANAGEMENT
➔ Audits
➔ Agreements
◆ Data Use Agreement (DUA)
➔ Policies & Procedures
➔ Education & Training
➔ Limits on Use / Collection
➔ Security
MORE CONTROLS

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THANK YOU!
QUESTIONS?

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REFERENCES
Garfinkel L. S. (2015). NIST 8053 De-Identification of Personal
Information. U.S. Department of Commerce. Gaithersburg, MD
Retreived from http://dx.doi.org/10.6028/NIST.IR.8053
Nelson S. G. (2015). Practical Implications of Sharing Data: A Primer on
Data Privacy, Anonymization, and De-Identification. ThotWave
Technologies. Chapel Hill, NC. Retreived from http://suppor
t.sas.com /resources/papers/proceedings15/1884-2015.pdf
Cavoukian A., Emam E. K. (2011). Dispelling the Myths Surrounding
De-identification Anonymization Remains a Strong Tool for
Protecting Privacy. Toronto, Canada. Retreived from https:
//www
.ipc.on.ca/images/Resources/anonymization.pdf