具有时空约束的TRBAC模型在OA中的应用

本文提出了一个基于TRBAC（Task—Kole Based Access Contr01）具有时空约束的工作流授权模型TSC—TRBAC（Temporarily-SpatiallyConstrained Task—RoleBased Access Contr01）。所谓时空约束即用户执行任务的时候，不仅受到时间约束，而且还受到空间限制，包括对物理空间和逻辑空间的限制，这使得工作流的安全性得以保证。通过将该模型应用到具体的系统中，表明了该模型的可行性。

Application of TRBAC model with temporal and spatial constraints in OA

A temporarily-spatially constrained model based on TRBAC （Task-Role Based Access Control ） is proposed in workflow system.Temporary and spatial Constraint is that user is not only constrained by temporality, but also constrained by spatiality when the task is executed by user.The model suggests that a property of security level should be increased in task.Task may have the property of high security level and low security level.It shows the feasibility by means of application in OA.