Abstract: To ensure the flexibility and efficiency of business,enterprises may outsource some tasks to be executed by business partners.Current service assessment systems are difficult to guarantee the authenticity and accuracy of Quality of Service (QoS) values for services.Blockchain technology can substitute these systems because of its advantages,but does not provide an efficient QoS assessment mechanism.To solve these issues,the feedback both from service providers and consumers was required.To avoid noises caused by malicious feedback,the comprehensive assessment algorithms were provided by combining Gaussian mixture and complex dynamic weighting models.Evaluations showed that the proposed framework and algorithms worked well in most cases.

Key words: block chain, smart contract, quality of service, service attributes, customer feedback, business process management

摘要： 企业为了保证自己业务的灵活性与高效性,经常需要购买外部服务来执行业务流程中的活动,然而现有服务评价体系很难保证评价的真实性与准确性。区块链技术凭借其分布式存储、共识机制以及智能合约等优势可以替代第三方来对服务进行评价。有研究者提出了一个基于区块链的框架来解决该问题,然而,该框架只存储用户反馈的服务质量(QoS)值,没有给出有效的QoS评价机制。为解决以上问题,提出了基于区块链与智能合约技术的存储服务属性、客户及反馈的Qos客观评价框架。同时,为了弥补区块链存储数据无法防止源头作弊的弊端,以及为用户提供更高的参考价值,提出高斯混合模型估参拆分和复杂动态赋权结合算法来对提供商与用户的QoS值进行综合评价。实验证明,所提方法基本能够有效过滤掉恶意评价,确保得出的QoS值在真实范围内。

关键词: 区块链, 智能合约, 服务质量, 服务属性, 客户反馈, 业务流程管理