The recent growth of the World Wide Web has sparked new research into using the Internet for novel types of group communication, like multiparty videoconferencing and real-time streaming. Multicast has the potential t...The recent growth of the World Wide Web has sparked new research into using the Internet for novel types of group communication, like multiparty videoconferencing and real-time streaming. Multicast has the potential to be very useful, but it suffers from many problems like security. To achieve secure multicast communications with the dynamic aspect of group applications due to free membership joins and leaves in addition to member's mobility, key management is one of the most critical problems. So far, a lot of multicast key management schemes have been proposed and most of them are centralized, which have the problem of 'one point failure' and that the group controller is the bottleneck of the group. In order to solve these two problems, we propose a Key Management Scheme, using cluster-based End-System Multicast (ESM). The group management is between both 1) the main controller (MRP, Main Rendezvous Point) and the second controllers (CRP, Cluster RP), and 2) the second controllers (CRPs) and its members. So, ESM simplifies the implementation of group communication and is efficient ways to deliver a secure message to a group of recipients in a network as a practical alternative to overcome the difficulty of large scale deployment of traditional IP multicast. In this paper, we analyze different key management schemes and propose a new scheme, namely Advanced Transition/Cluster Key management Scheme (ATCKS) and find it has appropriate performance in security.展开更多
文摘The recent growth of the World Wide Web has sparked new research into using the Internet for novel types of group communication, like multiparty videoconferencing and real-time streaming. Multicast has the potential to be very useful, but it suffers from many problems like security. To achieve secure multicast communications with the dynamic aspect of group applications due to free membership joins and leaves in addition to member's mobility, key management is one of the most critical problems. So far, a lot of multicast key management schemes have been proposed and most of them are centralized, which have the problem of 'one point failure' and that the group controller is the bottleneck of the group. In order to solve these two problems, we propose a Key Management Scheme, using cluster-based End-System Multicast (ESM). The group management is between both 1) the main controller (MRP, Main Rendezvous Point) and the second controllers (CRP, Cluster RP), and 2) the second controllers (CRPs) and its members. So, ESM simplifies the implementation of group communication and is efficient ways to deliver a secure message to a group of recipients in a network as a practical alternative to overcome the difficulty of large scale deployment of traditional IP multicast. In this paper, we analyze different key management schemes and propose a new scheme, namely Advanced Transition/Cluster Key management Scheme (ATCKS) and find it has appropriate performance in security.
文摘为了有效评估多直流送端系统在直流闭锁故障场景下新能源场站的暂态过电压(transient overvoltage, TOV)风险,提出了一种考虑新能源场站相互影响的暂态过电压幅值预测方法。首先,推导了直流闭锁故障引起的送端系统中新能源场站并网点暂态过电压幅值解析表达式。然后,提出了表征新能源多场站短路比(multiple renewable energy stations short circuit ratio, MRSCR)与新能源场站并网点暂态过电压幅值之间关联关系的近似解析表达式。鉴于MRSCR可以量化新能源场站间的耦合程度(亦即相互影响程度),在此基础上基于知识嵌入神经网络,提出了一种考虑新能源场站相互影响的直流闭锁场景下新能源场站暂态过电压幅值预测方法。该方法通过在损失函数中引入对MRSCR的正则化项,确保TOV幅值预测模型符合电力系统中的物理约束,从而提高预测结果的准确性。最后,在中国某地区实际电力系统上对所提方法进行了测试。实验结果表明,相较于传统TOV幅值预测方法,所提计及新能源场站相互影响的TOV幅值预测方法能够显著提升预测精度。
