Abstract: Business processes frequently change along with the changes of laws,technology and business environment.Therefore,it is necessary to timely adjust the process model and provide solutions to migrate partially executed process instances based on the old version of the process model.To address the problems of difficult process evolution and inefficient instance migration that commonly exist in the existing blockchain-based business process management engines,a version control-based process model evolution and process instance dynamic migration method named PMEVC-PIMOP was proposed.The timing-choreography was used to model frequent process dynamic changes,and a model version control strategy was proposed based on voting mechanism for process model evolution.At the same time,the state compliance of instances in the evolution process was considered,thereby solved the problem of difficult process model evolution on the chain.In addition,for the problem of dynamic changes of user process instances in operation,a dictionary tree-based candidate instance trajectory prefix matching algorithm was proposed to perform candidate process trajectory matching to obtain candidate model sets.After that,the optimal candidate model version selection algorithm based on the exact graph editing distance was adopted to select the optimal candidate model in the candidate model sets to support efficient migration of instances.

Key words: business process management, smart contract, version control, model evolution, instance migration

摘要： 业务流程会由于法律、技术或业务环境的变化而发生改变。因此,在业务流程管理中需要相应地调整流程模型,并提供解决方案以迁移部分按照旧版本流程模型执行但尚未结束的流程实例。针对现有基于区块链的业务流程管理引擎普遍存在的流程演化困难、实例迁移低效等问题,提出一种基于版本控制的流程模型演化和流程实例动态迁移方法（PMEVC-PIMOP）。该方法首先采用赋时编排图来对频繁变更的动态流程进行建模,然后提出基于投票机制的模型版本控制策略用于流程模型演化,并在演化过程中考虑了流程的状态合规性。此外,针对流程实例的动态变更问题,该方法首先提出了基于字典树的候选实例轨迹前缀匹配算法计算得到候选模型集合,之后基于精确图编辑距离在候选模型集合中选择最优模型进行实例的高效迁移。最后,在一家助听器企业的真实数据集上的实验表明,PMEVC-PIMOP能有效应对跨组织业务流程在链上的模型演化和实例迁移。

关键词: 业务流程管理, 智能合约, 版本控制, 模型演化, 实例迁移