# Dual Basis Measurement Based Protocol

This example protocol implements the task of Quantum E-voting. The protocol uses an entangled state with a special property as a blank ballot and is self-tallying i.e. The voters, without the presence of any trusted authority or tallier, need to verify that they share specific quantum states.

## Assumptions

• all classical communication in the protocol takes place using pairwise authenticated channels.

## Outline

We consider N voters who wish to cast their vote secretly. One of the voters prepares some states in two forms and each voter receives a specific particle of each state. After voters verify that they received correct states by cut and choose technique, they perform certain measurements on their qudits and cast their vote based on the measurement outcome.

In the end, all voters simultaneously broadcast their votes in encoded form and everyone can compute the election result by a simple summation.

## Notations

• ${\displaystyle V_{i}:i^{th}}$ voter
• c: number of possible candidates
• m: dimension of qudits
• ${\displaystyle \delta _{0}}$: security parameter
• N: number of voters
• ${\displaystyle v_{i}}$: vote of ${\displaystyle i^{th}}$ voter
• ${\displaystyle P_{N}}$: set of all possible permutations with N elements
• ${\displaystyle B_{k}:k^{th}}$ voter’s blank ballot

## Properties

• This protocol is not secure. (doesn’t satisfy quantum privacy property.)

We can construct an adversary that violates privacy by an attack on the cut and choose technique of the protocol with a non-negligible advantage in ${\displaystyle \delta _{0}}$.

## Requirements

• Quantum memory for each party to store qubits
• Measurement Devices for each party
• Quantum channel capable of sending qubits
• Classical channel to send multiple bits

## Further Information

*contributed by Sara Sarfaraz