Efficient Identity Theft Prevention using Aggregated Proof of Knowledge

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Efficient Identity Theft Prevention
usingAggregated Proof of Knowledge

• Elisa Bertino, Abhilasha Bhargav-Spantzel,
• Anna Squicciarini,
• Rui Xue

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What is Identity Theft?

• Identity Theft is the use of personally
  identifying information belonging to one
  individual by another individual for financial or
  personal gain.

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Multi-Factor Identity Verification
Require additional identity information as
proof to qualify to be the owner of the identity
attribute being used.
Example Real Life Scenario Requirement for
additional proofs of identity
I will use my credit card to pay
To use your credit card please show your drivers
license and an additional photo id for
verification of your identity
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Overview of our Approach

• We have a logical entity called the registrar
  which establishes and maintains identity
  commitments used to establish proof of knowledge
  of strong identifiers used later for multifactor
  identity verification.
• Two main Phases
• Enrollment or Registration User commits his
  strong identifiers to be used later as proofs of
  identity.
• Usage Before revealing the actual value of a
  required attribute one has to verify the
  commitments of other attributes as proofs of
  identity.

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Example
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Proving aggregated signature on committed values
To prove the knowledge of multiple identifiers.
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Integrating the zero-knowledge proof into the
verification
To prove the knowledge of secret commitments.
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Zero-knowledge proof a hidden signature
To prove the possession of signature.
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Efficiency Analysis

• Our signatures on commitments are short and the
  storage complexity is smaller than the ones
  computed with existing techniques Camenisch et.
  Al.04
• Our approach is more flexible in that whenever n
  messages are committed for a user, the user is
  able to to prove 2n-1 many combinations of them
  which does not appear possible in the existing
  schemes

Comparison of the number of exponentiations for
proving t factors
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Conclusion

• Identity theft is a major problem (FTC)
• Our approach supports the strong verification of
  identity attributes, which is a component of
  comprehensive solutions against identity theft