SecTEP: Enabling secure tender evaluation with sealed prices and quality evaluation in procurement bidding systems over blockchain

Abstract Numerous methods have been proposed in the past few years to perform tender evaluation in procurement bidding systems, such as cloud storage procurement bidding systems. However, most of the proposed approaches focus only on the bidding price comparison and bidding efficiency while neglecting supplier quality evaluation and bidding privacy. To the best of our knowledge, the existing studies on tender evaluation in procurement bidding systems either provide insufficient privacy protection or are only concerned with bidding prices. In this paper, for the first time, we propose SecTEP, a Sec ure T ender E valuation method with sealed prices and quality evaluation in P rocurement bidding systems over blockchain. SecTEP considers not only the bidding price but also the supplier’s quality, while protecting the privacy of the bidding and evaluation results. SecTEP is constructed using delicately designed cryptographic tools that perform bidding price validation, bidding price comparison, quality score aggregation, and winner declaration over encrypted values. Moreover, we customize a finer-grained algorithm for bidding price comparison to support price tie identification. Finally, we employ the blockchain technology to ensure a transparent, tamper-proof, and traceable implementation of SecTEP. Theoretical security analysis and performance evaluation ensure that SecTEP maintains a strong privacy of bidding prices while providing quality evaluation services for suppliers. Experimental results further demonstrate the validity of the theoretical analysis as well as the practical application of SecTEP in the real world.