关键词: 时态约束，策略组合，XACML，工作流

Abstract: In multi-domains environment, workflow access control policy is consisted of heterogeneous temporal policies in difference autonomic domains,and its requirement is special subjects can access special objects in perodic time or duration time. While XACML specifics policy combine, it does not contains temporal constraint. Based on the kinds of temporal constraint proposed by UTRBAC, this paper defined temporal constraints policies and illustrated by figures. It is extended from XACML by introducing correspond temporal constriant elements. Finally, this paper illustrated that the extended XACML can describe heterogeneous temporal policy combine conveniently through a example.

Key words: Temporal constraint, Policy combine, XACML, Workflow