一种基于区块链技术的公安执法电子证据系统的设计与实现  

Design and implementation of a public security law enforcement electronic evidence system based on blockchain technology

作　　者：王琪 张嘉政 刘文奇 WANG Qi;ZHANG Jiazheng;LIU Wenqi(Center of Data Science,Kunming University of Science and Technology,Kunming 650500,China;Yunnan Provincial Key Laboratory of Computer Technology Application,Kunming University of Science and Technology,Kunming 650504,China)

机构地区：[1]昆明理工大学数据科学研究中心,云南昆明650500 [2]昆明理工大学云南省计算机技术应用重点实验室,云南昆明650504

出　　处：《智能系统学报》2022年第6期1182-1193,共12页CAAI Transactions on Intelligent Systems

基　　金：国家自然科学基金项目(11971211,61573173)。

摘　　要：针对公安执法环境的复杂性和电子证据取证及证据固定的困难,根据公安执法场景中电子证据的功能需求,创建了一类基于区块链技术的公安执法电子证据模型的原型系统。该系统具备分布式、不可篡改、可溯源和安全性高等特点,较好地解决了公安执法电子证据在取证和诉讼中证据的易变性、逻辑混乱和时间不一致等核心问题。该系统将执法过程中涉及举证的数据上链,通过改进实用拜占庭将军容错(practical byzantine fault tolerance, PBFT)共识算法来监测试图篡改执法数据的行为,利用层级监管特性启动备用共识节点以提高整体效率,基于星际文件系统(interplanetary file system, IPFS)对超大文件上链进行数据存储,有利于公安系统在处理大型数据信息时做到及时、安全与高效。最后通过公安局办案大厅执法场景的测试与分析,验证了该系统的可行性。该系统的应用可赋能公安执法电子证据举证效力的提升和司法领域反腐倡廉,并为案件侦破的串并案智能化提供可靠的数据基础。We developed a prototype system for law enforcement electronic evidence data based on blockchain technology, focusing on the complexity of the law enforcement environment, the difficulties of electronic evidence collection and evidence fixation, and the functional requirements of electronic evidence in the scene of public security law enforcement. The system is distributed, non-tamperable, and traceable with a high level of security. It addresses the fundamental issues of variability, logic confusion, and time inconsistency in law enforcement electronic evidence collection and litigation for police. The system uploads the data involved in the law enforcement process to the chain, monitors the behavior of those attempting to tamper with the law enforcement data by improving the practical byzantine fault tolerance consensus algorithm, and uses the hierarchical supervision feature to activate the standby consensus node to improve overall efficiency. Based on the interplanetary file system, large files are uploaded to the chain and stored,which allows the public security system to process large-scale data in a timely, safe, and efficient manner. The feasibility of our system is validated by the test and analysis of the law enforcement scene in the case-handling hall of the public security bureau. The use of this system has the potential to improve the performance of law enforcement and anti-corruption efforts in the judicial field and provide a credible data foundation for the intelligentization of serial and parallel case detection.

关 键 词：区块链 电子证据 分布式存储 PBFT共识算法 数据库 异构共识 数据差分 公安执法 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]