The Time-constrained Permission Change Model Based On The Role In PLM System

PLM(Product Lifecycle Management)is a system which can manage all data information from the product design,product production,product's entire life cycle from in production to discontinued production.Its greatest feature is the ability to share information between different departments of an enterprise and promote the efficiency of collaborative work.For software systems,when it comes to interactive access to information,the requirements for access control technology will be very high.Therefore,based on the improvement of PLM access control technology,this paper proposes a role-based permission change model with time constraint.Access control technology is to control legitimate users who want to have the access to software systems and operate specific information resources.However,in the actual work process of enterprises,some users cannot complete the work in time for a variety of reasons and have to transfer the authority to other people to help them complete.This requires the access control technology to have the function of permission change.In the PLM system,permissions are divided into form permission and task node permission,which both establish relationships with users through roles.In the process of permission change,the transfer of these two permissions should be considered.When allocation is being initialized,permission will increase time constraint.So permission is limited by the active time during its lifetime.Before changing the permission,it is necessary to consider how the permission can be transferred.Therefore,the constraint change rules are indispensable.This paper focuses on the influence of time constraint on the authority change process.First of all,this model has improved many basic features such as partial permission change,change depthand change width by studying some comparatively mature permission change model.At the same time,it also adds time constraint,which constitutes the basic functions of permission change.Then,it describes the forms of permission change and revocation rules.With the above basic theory,not only is it able to describe the generation process of a permission change tree with a time constraint,but it also enables the permission change tree to describe the permission change relationship between users.Finally,we will discuss deeply different permission changes' and revocation methods' effect on the change of active time and the structure of permission change tree,and propose an effective solution.The model designed in this paper is eventually applied to the PLM system developed by labs and enterprises,which has improved the access control security of the system and also met the actual needs in the production management process of the enterprise.