Role based access control (RBAC)was proposed in 70's, and prevailed in 90's, and then Sandhu etc pro-posed formal RBAC model. Now RBAC is attracting increasing attention, and many governmental and commercial o...Role based access control (RBAC)was proposed in 70's, and prevailed in 90's, and then Sandhu etc pro-posed formal RBAC model. Now RBAC is attracting increasing attention, and many governmental and commercial or-ganizations have adopted it, its importance is more and more apparent. In this paper we illuminates the distinctionsand similarities of role and user groups, and based the model that was proposed by Sandhu, we examine the relation-ship of role hierarchies and role constraints and formally describes that, and explain the most important part of roleconstraints ,which is separation of duties.展开更多
Access Control(AC)is one of the important technologies of System Security and has been widely studied recently because the traditionary AC technologies can' t meet with the security commands of contemporary imform...Access Control(AC)is one of the important technologies of System Security and has been widely studied recently because the traditionary AC technologies can' t meet with the security commands of contemporary imformation system. As a result,the traditionary AC technologies have been developed and some new technologies have been put forward. This paper makes the necessary classification for the more-than-ten-year research results of the AC technology,together with the analysis and predication for the development trend of the AC technology in the future.展开更多
Ad hoc网络中的QoS保障问题是一个比较复杂的开放问题。本文首先介绍了Ad hoc网络中提供QoS保证的各种困难,然后详细讨论了动态服务质量保证机制以及具有QoS能力的中间适配机制,接着介绍了支持QoS的MAC协议和其它一些相关的QoS保障机制...Ad hoc网络中的QoS保障问题是一个比较复杂的开放问题。本文首先介绍了Ad hoc网络中提供QoS保证的各种困难,然后详细讨论了动态服务质量保证机制以及具有QoS能力的中间适配机制,接着介绍了支持QoS的MAC协议和其它一些相关的QoS保障机制,最后讨论了QoS的衡量尺度和QoS路由,并给出了结论。展开更多
文摘Role based access control (RBAC)was proposed in 70's, and prevailed in 90's, and then Sandhu etc pro-posed formal RBAC model. Now RBAC is attracting increasing attention, and many governmental and commercial or-ganizations have adopted it, its importance is more and more apparent. In this paper we illuminates the distinctionsand similarities of role and user groups, and based the model that was proposed by Sandhu, we examine the relation-ship of role hierarchies and role constraints and formally describes that, and explain the most important part of roleconstraints ,which is separation of duties.
文摘Access Control(AC)is one of the important technologies of System Security and has been widely studied recently because the traditionary AC technologies can' t meet with the security commands of contemporary imformation system. As a result,the traditionary AC technologies have been developed and some new technologies have been put forward. This paper makes the necessary classification for the more-than-ten-year research results of the AC technology,together with the analysis and predication for the development trend of the AC technology in the future.
