Quorum systems have been used to solve the problem of data consistency in distributed fault-tolerance systems. But when intrusions occur, traditional quorum systems have some disadvantages. For example, synchronous qu...Quorum systems have been used to solve the problem of data consistency in distributed fault-tolerance systems. But when intrusions occur, traditional quorum systems have some disadvantages. For example, synchronous quorum systems are subject to DOS attacks, while asynchronous quorum systems need a larger system size （at least 3f＋1 for generic data, and f fewer for self-verifying data）. In order to solve the problems above, an intrusion-tolerance quorum system （ITQS） of hybrid time model based on trust timely computing base is presented （TTCB）. The TTCB is a trust secure real-time component inside the server with a well defined interface and separated from the operation system. It is in the synchronous communication environment while the application layer in the server deals with read-write requests and executes update-copy protocols asynchronously. The architectural hybridization of synchrony and asynchrony can achieve the data consistency and availability correctly. We also build two kinds of ITQSes based on TTCB, i.e., the symmetrical and the asymmetrical TTCB quorum systems. In the performance evaluations, we show that TTCB quorum systems are of smaller size, lower load and higher availability.展开更多
针对现有的基于身份加密(identity based encryption,IBE)体系中缺乏权限管理问题,提出一种基于信任服务IBE体系下的权限管理方案.该方案采用门限的思想和算法对服务进行集中管理,并结合基于角色的访问控制管理权限,实现了细粒度的权限...针对现有的基于身份加密(identity based encryption,IBE)体系中缺乏权限管理问题,提出一种基于信任服务IBE体系下的权限管理方案.该方案采用门限的思想和算法对服务进行集中管理,并结合基于角色的访问控制管理权限,实现了细粒度的权限管理.采用信任继承的思想为用户分配角色,并采用集中审计的思想维护系统,提高了系统的可靠性.展开更多
基金supported by the National Natural Science Foundation of China (60774091)
文摘Quorum systems have been used to solve the problem of data consistency in distributed fault-tolerance systems. But when intrusions occur, traditional quorum systems have some disadvantages. For example, synchronous quorum systems are subject to DOS attacks, while asynchronous quorum systems need a larger system size （at least 3f＋1 for generic data, and f fewer for self-verifying data）. In order to solve the problems above, an intrusion-tolerance quorum system （ITQS） of hybrid time model based on trust timely computing base is presented （TTCB）. The TTCB is a trust secure real-time component inside the server with a well defined interface and separated from the operation system. It is in the synchronous communication environment while the application layer in the server deals with read-write requests and executes update-copy protocols asynchronously. The architectural hybridization of synchrony and asynchrony can achieve the data consistency and availability correctly. We also build two kinds of ITQSes based on TTCB, i.e., the symmetrical and the asymmetrical TTCB quorum systems. In the performance evaluations, we show that TTCB quorum systems are of smaller size, lower load and higher availability.
文摘针对现有的基于身份加密(identity based encryption,IBE)体系中缺乏权限管理问题,提出一种基于信任服务IBE体系下的权限管理方案.该方案采用门限的思想和算法对服务进行集中管理,并结合基于角色的访问控制管理权限,实现了细粒度的权限管理.采用信任继承的思想为用户分配角色,并采用集中审计的思想维护系统,提高了系统的可靠性.
