COMP 7370 Advanced Computer and Network Security The MinGen Algorithm

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COMP 7370 Advanced Computer and Network
SecurityThe MinGen Algorithm
Dr. Xiao Qin Auburn Universityhttp//www.eng.aubu
rn.edu/xqin xqin_at_auburn.edu
Spring, 2011
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Step 1 PT vs. PTQI
vs.
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Step 2 history lt- d_1, d_n
Use subscripts to represent generalization
strategies.
n 2 E_0 -gt d_1 0 Z_0 -gt d_2 0
E_1 -gt d_1 ? Z_2 -gt d_2 ?
E_1 -gt d_1 1 Z_2 -gt d_2 2
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Step 2 history lt- d_1, d_n
Note E_i and Z_j must be specific when you
implement the MinGen algorithm. You must specify
your generalization strategies. For example
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Step 2 E_i, Z_j
n 2 E_0 -gt d_1 0 Z_0 -gt d_2 0
E_1 -gt d_1 ? Z_2 -gt d_2 ?
E_1 -gt d_1 1 Z_2 -gt d_2 2
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Step 3 Check single attributes

• Each single attribute must satisfy k-anonymity

E -gt MGTE v a -gt freq(a, MGTE) ? If 4 lt
k then what does this mean?
What should we do?
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Step 3.1 Check single attributes

• Each single attribute must satisfy k-anonymity

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If 4 lt k then we need data generalization! V_E
d_E, d_Z 1, 0 not 0, 1 Note move one
step at a time.
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Step 3.2 the generalize() function

• Each single attribute must satisfy k-anonymity

E -gt MGTE Value v a -gt freq(a, MGTE)
? If 4 lt k then what does this mean? V_E
d_E, d_Z 1, 0 MGT lt- generalize(MGT, V_E,
0,0)
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Step 3.2 the generalize() function

• Each single attribute must satisfy k-anonymity

MGT lt- generalize(MGT, v, h) Generalize()
transform MGT based on a generalization strategy
specified by v, h.
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Step 3.3 update the history vector

• Each single attribute must satisfy k-anonymity

Can you give me an example to illustrate how step
3.3 works?
History d_E, d_Z 0, 0 V_E 1, 0 New
History 0, 0 1, 0 1, 0