Abstract: Aiming at the trust problem among users in the construction process of distributed k-anonymity technology, an anonymous zone construction scheme combining credit evaluation and smart contracts is proposed. First, multiple attributes involved in the anonymous zone construction process are introduced to quantify the user's credit indicators in the anonymous zone construction and convert them into credit values through a multi-attribute decision making (MADM). Second, combined with blockchain technology, a smart contract function based on credit value evaluation is designed. Finally, the smart contract function verifies the user's identity information and automatically calculates the user's reputation value, and requests the user and collaborative users to only interact through the smart contract to complete the construction of the anonymous area. The experimental results show that the proposed scheme has lower communication overhead and calculation delay, which ensures the generation efficiency of anonymous regions and provides better protection for users' location privacy.

Key words: creditevaluation; location privacy, multi-attribute decision making, blockchain, smart contract