Privacy-preserving computation and robust watermarking techniques for healthcare data
Author
Sav, Sinem
Advisor
Ayday, Erman
Date
2018-08Publisher
Bilkent University
Language
English
Type
ThesisItem Usage Stats
150
views
views
0
downloads
downloads
Abstract
Health and genomic data is sensitive in terms of carrying private information
about individuals. One can infer inherited/genetic disorders, their occurrence
probabilities, information about race, and kinship by analyzing an individual's
genomic data. Furthermore, health data which is mostly collected by hospitals
or other health institutions carries private information about individuals including
the diseases they have at present or indicators of future diseases/disorders.
While protecting such data, it is important to show that its utility is preserved
and maximized since the data is used in researches. Regarding these facts, homomorphic
encryption-based scheme (using Paillier cryptosystem) for the protection
of health data and a novel watermarking scheme based on belief propagation algorithm
for the genomic data is proposed in this work. Homomorphic encryption
is used for the health data to show the ability of performing mathematical operations
on the encrypted data without decrypting it with a real-life use-case. We
show its practicality with the correctness and performance results. In the second
part of this thesis, a watermarking scheme for genomic data is proposed to overcome
the liability issues due to unauthorized sharing by service providers (SPs).
Robust-watermarking techniques ensure the detection of malicious parties with a
high probability and we show the probabilistic limits of this detection with di erent
experimental setups and evaluation metrics. Lastly, this scheme guarantees
the following with a high probability: (i) the utility is preserved, (ii) it is robust
against single or colluding SP attacks, and (iii) watermark addition is compatible
with the nature of the data as the proposed method considers auxiliary information
that a malicious SP may use in order to remove/modify watermarked points
before leaking the data.