Design And Implementation Of Blockchain-based DRE Electronic Election System

In the past 20 years,there has been a strong interest in the academic research of electronic elections.Because electronic elections avoid the time and space restrictions of traditional election methods,and have better security and privacy,they gradually replace traditional election methods.One type of electronic election system based on DRE equipment has attracted much attention because of its public and verifiable election process and independent of the tallying authorities.However,the unresolved issues such as whether the integrity is fully guaranteed,whether the ballots counted in the election result are legal or not,etc.make it have certain defects,which leads to greater restrictions on its application scenarios.Therefore,this dissertation is going to improve this type of election system.Firstly,this dissertation focuses on the necessary features of the DRE election system,including privacy,integrity(that is,end-to-end verifiability,including cast as intended,recorded as cast,and tallied as recorded),legitimacy,robustness,etc.,and analyze the defects in its latest research results(DRE-i and DRE-ip).Firstly,this type of election system with integrity as the design goal is based on model assumptions that have a great impact on integrity itself,such as channel security in the system,and the content of the bulletin board cannot be tampered with,resulting in insufficient protection of system integrity;Secondly,this type of election system only supports the election rules of “one out of two” instead of“one out of multiple”,which imposes certain restrictions on the application scenarios of this type of system;Third,like most systems in the field of software engineering,this type of election system lacks the consideration of the robustness.Then,based on the above system defects,the specific improvement scheme is designed and implemented.The specific work includes:(1)Based on the Fabric permissioned blockchain platform,a bulletin board server suitable for the DRE election system was built.Organizations belonging to different interest groups in the Fabric network jointly maintain the same copy of the ledger that contains election data,making it free from the model assumptions and with tamper-proof modification truely,achieving “recorded as cast”.(2)The introduction of digital signature technology based on asymmetric encryption in the communication process of the system,not only the anti-counterfeiting of communication data is realized,but also the illegal requests from non designated devices can be filtered,so that the legitimacy of the election system is initially achieved.(3)Constructing a Zero-Knowledge Proof scheme under the “one out of multiple” election rules,which can prove to the election verifiers that all ballots entered into the election system are legal without exposing any ballot content,thereby further achieving the legitimacy of the election system.(4)Realizing the statistical scheme and verification scheme of the election results under the“one out of multiple” election rules to ensure that all legal ballots have been counted into the election results,so as to realize the “tallied as recorded”.(5)For the sensitive election data in DRE devices,the Shamir secret sharing and secret recovery schemes are used to achieve the secure backup and fault-tolerant recovery of election data without affecting the system privacy,so as to improve the robustness of the system to a certain extent.In the end,by completing the system docking with DRE terminal equipment with a trusted execution environment that guarantees privacy and “cast as intended”,it is proved that this dissertation has a certain feasibility to improve the integrity,legitimacy and robustness of the DRE election system.Therefore,the research work done in this dissertation has a certain practical significance.