Anual Workshop February 5th, 2014
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Transcript of Anual Workshop February 5th, 2014
Anual WorkshopFebruary 5th, 2014
Anonymous yet reliable ePoll application
Italo DacostaSecAnon-DistriNet
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Electronic Polls/Elections
• Gathering opinions on a particular topic
• Determining the most popular choice over a set of options
• Typically targeted to a particular group of people
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Problems
• Generally identifiable– Integrity vs. anonymity
• Users less motivated to freely participate and express opinions
• Users cannot verify their votes– Need to trust the poll organizer
• Difficult to restrict to a target group
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Our Approach
• Rely on anonymous credentials for ballot privacy– PriMan framework
• Design verification capabilities for the bulletin board– Individual verifiability– Universal verifiability– Eligibility verifiability
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Anonymous Credentials
Authentication with a classical credential (X.509)
Name: John DoeGender: MBirthdate: 01/01/1970Address: street 10, LeuvenZip code: 3000 Si
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Proof
Authentication with anonymous credential (Idemix)
Name: John DoeGender: MBirthdate: 01/01/1970Address: street 10, LeuvenZip code: 3000 Si
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Proof
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Our Scenario
• Low to medium scale polls/elections• Low to medium coercion
– E.g., No high-stakes elections
• Untrusted poll organizer– But trusted credential issuer
• Voting over the Internet
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Our ePoll Architecture
Credential Issuance
Issuer ServerCredential Storage &
Retrieval
Account Manager Server
Voting
ePoll Server
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ePoll Protocols
• Registration protocol– Obtain ePoll anonymous credential from Issuer server– User validation (e.g. only one ePoll credential per user)
– E.g., eID, workshop registration number
• Storage & Retrieval protocol– ePoll credentials are securely stored in the Account Manager
server– User authenticates to retrieve her credentials on her desktop
computer or smartphone
• Voting protocol– User selects a poll to participate– User uses her ePoll app and credential to participate in the poll– User can validate their vote was successfully submitted
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Vote Verification
• Poll Integrity Value (PIV)– PIVi = H(i | PIVi-1 | datai)
• Poll Authenticity Value (PAV)– Sign(SK, i | PID | PIVi)
• Work in progress
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Bulletin Board
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Implementation
• Java• PriMan framework• Mobile and Desktop client
ePoll Demonstrator
Questions?
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