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Ali Fawzi Najm Al-Shammari PhD Student-Free University of Bolzano-Italy

Lecturer at Faculty of Computer Science - Kerbala University alifawzi@uokerbala.edu.iq

An Overview of E-Voting Systems and Vote Verification Techniques

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Outlines

• Introduction

• E-Voting Systems

• Verifiability

• Vote Verification Techniques

• Conclusion

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Introduction• An election is a formal decision-making process by

which a population chooses an individual to hold elected status.

• Voting systems are the tools of any election.!

• Voting systems must fulfil with a set of requirements.

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For instance :

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Voting Requirements

Integrity (Accuracy) "Vote cast, and count as intended.

Privacy"Anonymity"

Receipt freeness"

Usability"‒ Any voter without a previous

experience can use the system.

Accessibility"‒ Any voter can vote

independently including illiterate and disabled.

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[Jeroen V. 2009, Tigran A. 2009]

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• E-Voting, the use of technology to facilitate one or more elections processes, e.g.,:"

Record, store, and count votes electronically. "

Announcing result."

Voters’ authorization."

• Motivation ?"Speed up the precess!

More usable!

Less voter mistakes!

Supports illiterates and disabled voters

Introduction (Motivation)

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• In-person e-voting"Still a voter needs to visit a polling station .!

Using a dedicated machine, in a controlled environment.!

• Online (Internet) e-voting"A voter can vote at home!

Using a personal device (PC, smart phone, ….)

Introduction (Types)

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• Direct Recording Electronics (DRE)"Dedicated computer

Touch screen

Flash memory

Head set

E-Voting Systems (In-person)

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• Optical Scan Systems "Scanner device

Paper ballot

Flash memory

No assistive technology!

E-Voting Systems (In-person)

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• Online Voting "Personal Device

Voting Application

Cryptography

Can we trust a personal device?

Family voting?

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E-Voting Systems (Online Voting)

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• Electronic systems are not transparent enough for voter."

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• Therefore, their adoption has been slow and criticized !!

E-Voting Systems (Transparency)

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The Major Causes ...

• Machines are subject to programming error, equipment malfunction and malicious tampering!"

• Programs are proprietary information and are not open to inspection!"

• Procedural and Environmental implications!"

• ... also do we “trust officials” ?

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Verifiability

• Support a voter, election official, and public entities with an evidence about the integrity of election results .

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Types of Verification

• Individual (Voter) verifiability"

Supporting a voter with an evidence that his/her vote has been captured, cast, and count as intended."

• Universal (Public) verifiability"

Supporting the election officials, and public entities with an evidence that the count votes are the same as intended by voters.

• Eligibility (Public) verifiability"

Each count vote comes from single eligible voter.

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Vote Verification

• Could supports: "

- Integrity , verifiability reaquirements.!

• Challenges:"

- Privacy, usability.!

Next, examples for vote verification techniques

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• Used with DRE systems!• Vote verified over a voice message heard through a headset!• Verification voice stored in type as an evidence

VVAATT [T. Selker]

(Voter Verified Audio Audit Transcript Trail)!

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VVPAT [R. Mercuri]

- A voter verifies his/her vote by reading printed paper trail. !!

- A voter can’t take the printed trail. !!

-Trails stored in safe box attached to the DRE and used for auditing later.

(Voter Verifiable Paper Audit Trail)!

Printed Peper Trail

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VVAATT & VVPAT (Pros & Cons)

• Advantages"

Easy to use."

Trails are physical evidence."

• Disadvantages"

Manual auditing."

Does not allows the voter to verify the full life cycle of the his/her vote (Not an End to End Verification method)"

Votes order could be reviled."

Voter language !!

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Electronic Trails [e.g., Pnyx.VM by Scytl]

- Votes verified through an electronic verification device."!

- Electronic copy of verified votes stored in the verification device to be used for recounting.

Verification device

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Pnyx.VM (Pros & Cons)

• Advantages"

Easy to use."

Automatic Auditing."

• Disadvantages"

Does not support End to End verifiability."

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How to provides an End to End verifiability without compromising privacy requirement ?

The magic of cryptography!

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VoteHere & Votegrity [D. Chaum]

- Partial information about ballot encrypted in receipt and given to voter for end-to-end verifications

printer

Encrypted receipt

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Scantegrity [D. Chaum] & Pret a Voter [P. Ryan]

- Partial information about ballot encrypted in receipt and ! given to voter for end-to-end verifications

Optical scanner

Encrypted receipt

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Cryptography (Pros & Cons)

• Advantages"

Supports an End-to-End verification."

Hard to be compromised."

• Disadvantages"

Not so usable."

What about long term privacy ?

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Problem

• Current verification methods still not able to cover all threats and challenges !!!

• Eligibility verifiability still weakly supported.

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Conclusion

• Any critical system could be compromised by:"

A failure."

An attack (insider or outsider)."

• Regular system provides receipts to any user to verify the integrity of his/her data."

• In E-Voting system it is not possible to provide such receipts"

Vote must be anonymous."

A voter must not be able to approve to any one about how he/she voted. ���25

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Conclusion

• However, Academic and Industrial sectors provides some techniques that balancing between"

allowing vote verification, and"

keeping the privacy and receipt freeness requirements."

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Thanks For Your Attention"!

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Welcome to any possible collaboration"

alifawzi@uokerbala.edu.iq