SLIDE 1
In
- Introduction. Mix
ixes.
2
The adversary is able to learn Alice’s sending profile!!! MIX
Understanding the Effects of Real-World Behavior in Statistical - - PowerPoint PPT Presentation
Understanding the Effects of Real-World Behavior in Statistical - - PowerPoint PPT Presentation
Understanding the Effects of Real-World Behavior in Statistical Disclosure Attacks Simon Oya , Carmela Troncoso and Fernando Prez-Gonzlez In Introduction. Mix ixes. MIX The adversary is able to learn Alices sending profile!!! 2 In
SLIDE 2
SLIDE 3
In
- Introduction. Mix
ixes.
3
Anonymity? How?
- Changing appearance
(re-encryption) MIX
SLIDE 4
In
- Introduction. Mix
ixes.
4
Anonymity? How?
- Changing appearance
(re-encryption) MIX The adversary is able to learn Alice’s sending profile with the timing information!!!
SLIDE 5
In
- Introduction. Mix
ixes.
5
ANONYMOUS Anonymity? How?
- Changing appearance
(re-encryption)
- Removing timing
information (delays) MIX
SLIDE 6
In
- Introduction. LSDA (I)
(I)
SLIDE 7
In
- Introduction. LSDA (I)
(I)
7
SLIDE 8
In
- Introduction. LSDA (I)
(I)
8
Least-Squares Disclosure Attack
SLIDE 9
In
- Introduction. LSDA (II
(II)
9
SLIDE 10
Real data:
10
220.000 emails sent between employees of Enron Corporation. http://www.cs.cmu.edu/~./enron/ 400.000 location check-ins from Gowalla social networking website. http://snap.stanford.edu/data/loc-gowalla.html 180.000 posts to the public mailing lists of Indimedia http://lists.indimedia.org/
SLIDE 11
Motivation: LSDA’s analysis falls short
11
SLIDE 12
Real-World Behavior. In Input process.
12
Emails dataset
SLIDE 13
Real-World Behavior. Output process.
#messages Email Location Mailing List =2 1.85 1.03 1.29 =3 2.71 1.05 1.46 =4 3.53 1.06 1.53 =5 4.40 1.08 1.53 ≥6 13.56 1.11 1.57
13
Average number of receivers chosen
SLIDE 14
New Theoretical Analysis (I) (I)
14
Multinomial output Maximum variance output “uniformity” Number of rounds observed Variance of the number
- f messages sent
Global contribution Individual term
SLIDE 15
New Theoretical Analysis (II (II)
15
SLIDE 16
Results
16
SLIDE 17
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