This document describes the Security Evaluated Standardized PasswordAuthenticated Key Exchange (SESPAKE) protocol. The SESPAKE protocol provides password-authenticated key exchange for usage in systems for protection of sensitive information. The security proofs of the protocol were made for situations involving an active adversary in the channel, including man-in-the-middle (MitM) attacks and attacks based on the impersonation of one of the subjects.

There are many papers whose authors propose various approaches to the construction of electronic voting (e-voting) systems that are resistant to various types of attacks. The two main properties of such systems are anonymity and verifiability. To provide anonymity, a blind signature or a ring signature is often used. To provide verifiability, distributed ledger technologies, in particular blockchain, have recently been used. One of these systems has been presented at ICCSA 2019. This system is implemented using Hyperledger Fabric blockchain platform and uses a blind signature to provide anonymity. One of the disadvantages of this system is that a compromised signer (an organizer generating a blind signature) could independently create valid ballots without detection. In this paper, we modify this system by replacing a blind signature with a linkable ring signature in order to eliminate this disadvantage. As a result, we combine linkable ring signature, Idemix and blockchain technologies to construct a decentralized anonymous e-voting system that does not rely on a trusted signer and can achieve the following properties: eligibility, unreusability, anonymity, and verifiability. In addition, the use of both a linkable ring signature and Idemix allows us to construct a two-stage anonymization, that increases the versatility of the proposed system. This allows us to use a blockchain platform (for example, Hyperledger Fabric) to implement the e-voting system, without making changes to platform standard signature scheme.