The Study On Specification,Execution And Recovery Strategy Of Transactional Workflow

The workflow management is a prevailing field researched by commerce and academic organizatons. But at present,there seem to be much deficiencies on the correctness and reliability of workflow and it can not meet the practical needs very well.In this paper,we introduce some transactional properties to workflow and put forward a nested workflow model with transactional characteristics.This model includes nested tasks and dependencies between the tasks,and it is provided with some ATM properties such as relaxed isolation and atomicity.Further more,we discuss the execution mechanism , system recovery and error handling of workflow on the base of the transactional characteristics.By defining consistency unit and execution atomic unit,we loosen the failure atomicity, serializability of concurrent worflow and isolation between tasks,thus,workflow meets the needs of the application semantics more flexiblly with high correctness and reliability.