Abstract: Role-activity based delegation model for CSCW with time and constraint characters is proposed based on the important properties of role and activity, and CSCW access control architecture and delegation mechanism are described in the basis of the model. It solves authorization centralization in the actual application of graphics and images collaboration processing based on CSCW, and realizes distributed and dynamic time characters.

Key words: Access control; Computer support cooperative work; Delegation; Time-order character; Constraint rule

摘要： 基于角色和活动的重要特性，提出了一种面向CSCW 环境基于角色-活动并具有时序特征和约束规则的委托授权模型RABDM forCSCW，以及CSCW 访问控制体系架构和委托授权工作机制。该模型解决了基于CSCW 图形图像协同处理实际应用中访问授权过于集中的问题，实现了分布式和动态时序性等特征。

关键词: 访问控制；CSCW；委托授权；时序特征；约束规则