The rapid increase in resource sharing across domains in the cloud comput- ing environment makes the task of managing inter-domain access control policy integration difficult for the security administrators. Al- thoug...The rapid increase in resource sharing across domains in the cloud comput- ing environment makes the task of managing inter-domain access control policy integration difficult for the security administrators. Al- though a number of policy integration and sec- urity analysis mechanisms have been devel- oped, few focus on enabling the average ad- ministrator by providing an intuitive cognitive sense about the integrated policies, which considerably undermines the usability factor. In this paper we propose a visualization flame- work for inter-domain access control policy integration, which integrates Role Based Ac- cess Control （RBAC） policies on the basis of role-mapping and then visualizes the inte- grated result. The role mapping algorithm in the framework considers the hybrid role hier- archy. It can not only satisfy the security con- straints of non-cyclic inheritance and separa- tion of duty but also make visualization easier. The framework uses role-permission trees and semantic substrates to visualize the integrated policies. Through the interactive policy query visualization, the average administrator can gain an intuitive understanding of the policy integration result.展开更多
Information sharing is a critical task for group-living animals. The pattern of sharing can be modeled as a network whose structure can affect the decision-making performance of individual members as well as that of t...Information sharing is a critical task for group-living animals. The pattern of sharing can be modeled as a network whose structure can affect the decision-making performance of individual members as well as that of the group as a whole. A fully connected network, in which each member can directly transfer information to all other members, ensures rapid sharing of important information, such as a promising foraging location. However, it can also impose costs by amplifying the spread of inaccur- ate information （if, for example the foraging location is actually not profitable）. Thus, an optimal net- work structure should balance effective sharing of current knowledge with opportunities to discover new information. We used a computer simulation to measure how well groups characterized by dif- ferent network structures （fully connected, small world, lattice, and random） find and exploit resource peaks in a variable environment. We found that a fully connected network outperformed other struc- tures when resource quality was predictable. When resource quality showed random variation, however, the small world network was better than the fully connected one at avoiding extremely poor outcomes. These results suggest that animal groups may benefit by adjusting their informa- tion-sharing network structures depending on the noisiness of their environment.展开更多
基金supported in part by National Key Basic Research Program of China (973 Program) under Grant No.2013CB329603National Natural Science Foundation of China under Grant No.60903191
文摘The rapid increase in resource sharing across domains in the cloud comput- ing environment makes the task of managing inter-domain access control policy integration difficult for the security administrators. Al- though a number of policy integration and sec- urity analysis mechanisms have been devel- oped, few focus on enabling the average ad- ministrator by providing an intuitive cognitive sense about the integrated policies, which considerably undermines the usability factor. In this paper we propose a visualization flame- work for inter-domain access control policy integration, which integrates Role Based Ac- cess Control （RBAC） policies on the basis of role-mapping and then visualizes the inte- grated result. The role mapping algorithm in the framework considers the hybrid role hier- archy. It can not only satisfy the security con- straints of non-cyclic inheritance and separa- tion of duty but also make visualization easier. The framework uses role-permission trees and semantic substrates to visualize the integrated policies. Through the interactive policy query visualization, the average administrator can gain an intuitive understanding of the policy integration result.
文摘Information sharing is a critical task for group-living animals. The pattern of sharing can be modeled as a network whose structure can affect the decision-making performance of individual members as well as that of the group as a whole. A fully connected network, in which each member can directly transfer information to all other members, ensures rapid sharing of important information, such as a promising foraging location. However, it can also impose costs by amplifying the spread of inaccur- ate information （if, for example the foraging location is actually not profitable）. Thus, an optimal net- work structure should balance effective sharing of current knowledge with opportunities to discover new information. We used a computer simulation to measure how well groups characterized by dif- ferent network structures （fully connected, small world, lattice, and random） find and exploit resource peaks in a variable environment. We found that a fully connected network outperformed other struc- tures when resource quality was predictable. When resource quality showed random variation, however, the small world network was better than the fully connected one at avoiding extremely poor outcomes. These results suggest that animal groups may benefit by adjusting their informa- tion-sharing network structures depending on the noisiness of their environment.
