The contents,the basic characteristics and the composition of the Art-net protocal is discussed in this article. The products which adopt this protocal are introduced as well.
网络的宗旨是更容易地在计算机间共享信息。信息共享,在 Linux 机器之间或与任何的 Unix主机,是容易的——诸如 FTP 和 NFS 之类的工具是现成的,也容易设置。不过不幸的是,即使是死心踏地的 Linux 狂热分子也不得不承认在这个世界上大...网络的宗旨是更容易地在计算机间共享信息。信息共享,在 Linux 机器之间或与任何的 Unix主机,是容易的——诸如 FTP 和 NFS 之类的工具是现成的,也容易设置。不过不幸的是,即使是死心踏地的 Linux 狂热分子也不得不承认在这个世界上大多数的 PC 使用的是 Windows展开更多
Location-aware applications have been used widely with the assistance of the latest positioning features in Smart Phone such as GPS,AGPS,etc.However,all the existing applications gather users' geographical data an...Location-aware applications have been used widely with the assistance of the latest positioning features in Smart Phone such as GPS,AGPS,etc.However,all the existing applications gather users' geographical data and transfer them into the pertinent information to give meaning and value.For this kind of solutions,the user's privacy and security issues might be raised because the geographical location has to be exposed to the service provider.A novel and practical solution is proposed in this article to provide the relative location of two mobile users based on their WiFi scanned results without any additional sensors.There is no privacy concern in this solution because end users will not collect and send any sensitive information to the server.This solution adopts a Client/Server(C/S) architecture,where the mobile user as a client reports the ambient WiFi APs and the server calculates the distances based on the WiFi AP's topological relationships.A series of technologies are explored to improve the accuracy of the estimated distance and the corresponding algorithms are proposed.We also prove the feasibility with the prototype of "Circle Your Friends" System(CYFS) on Android phone which lets the mobile user know the distance between him and his social network friends.展开更多
With the rapid developments of information technology,various industries become much more dependent on networks.Driven by economic interests and the game between countries reflected by growing cyberspace confrontation...With the rapid developments of information technology,various industries become much more dependent on networks.Driven by economic interests and the game between countries reflected by growing cyberspace confrontations,evasive network attacks on information infrastructures with high-tech,high concealment and longterm sustainability become severe threats to national security.In this paper,we propose a novel two-phased method for the detection of evasive network attacks which exploit or pretend to be common legal encryption services in order to escape security inspection.Malicious communications which camouflage themselves as legal encryption application are identified in the SSL'session structure verification phase firstly,and then by serverside X.509 certificate based anomaly detection,suspicious attack behaviors are further distinguished effectively.Experiment results show that our method is very useful for detecting the network activities of certain unknown threats or new malwares.Besides,the proposed method can be applied to other similar services easily.展开更多
In traditional framework,mandatory access control(MAC) system and malicious software are run in kernel mode. Malicious software can stop MAC systems to be started and make it do invalid. This problem cannot be solved ...In traditional framework,mandatory access control(MAC) system and malicious software are run in kernel mode. Malicious software can stop MAC systems to be started and make it do invalid. This problem cannot be solved under the traditional framework if the operating system(OS) is comprised since malwares are running in ring 0 level. In this paper,we propose a novel way to use hypervisors to protect kernel integrity and the access control system in commodity operating systems. We separate the access control system into three parts: policy management(PM),security server(SS) and policy enforcement(PE). Policy management and the security server reside in the security domain to protect them against malware and the isolation feather of the hypervisor can protect them from attacks. We add an access vector cache(AVC) between SS and PE in the guest OS,in order to speed up communication between the guest OS and the security domain. The policy enforcement module is retained in the guest OS for performance. The security of AVC and PE can be ensured by using a memory protection mechanism. The goal of protecting the OS kernel is to ensure the security of the execution path. We implementthe system by a modified Xen hypervisor. The result shows that we can secure the security of the access control system in the guest OS with no overhead compared with modules in the latter. Our system offers a centralized security policy for virtual domains in virtual machine environments.Keywords: hypervisor; virtualization; memo-展开更多
文摘The contents,the basic characteristics and the composition of the Art-net protocal is discussed in this article. The products which adopt this protocal are introduced as well.
基金supported by HONG KONG RGC and HONG KONG PolyU under the Grant G-U752/PolyU5103/09Ethe National Natural Science Foundation of Chinaunder Grant No.61003040,No.61202354
文摘Location-aware applications have been used widely with the assistance of the latest positioning features in Smart Phone such as GPS,AGPS,etc.However,all the existing applications gather users' geographical data and transfer them into the pertinent information to give meaning and value.For this kind of solutions,the user's privacy and security issues might be raised because the geographical location has to be exposed to the service provider.A novel and practical solution is proposed in this article to provide the relative location of two mobile users based on their WiFi scanned results without any additional sensors.There is no privacy concern in this solution because end users will not collect and send any sensitive information to the server.This solution adopts a Client/Server(C/S) architecture,where the mobile user as a client reports the ambient WiFi APs and the server calculates the distances based on the WiFi AP's topological relationships.A series of technologies are explored to improve the accuracy of the estimated distance and the corresponding algorithms are proposed.We also prove the feasibility with the prototype of "Circle Your Friends" System(CYFS) on Android phone which lets the mobile user know the distance between him and his social network friends.
基金supported by the National Science and Technology Support Program under Grant No.2012BAH46B02 and 2012BAH45B01the National High Technology Research and Development Program(863 Program) of China under Grant No.2011AA010703the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No.XDA06030200
文摘With the rapid developments of information technology,various industries become much more dependent on networks.Driven by economic interests and the game between countries reflected by growing cyberspace confrontations,evasive network attacks on information infrastructures with high-tech,high concealment and longterm sustainability become severe threats to national security.In this paper,we propose a novel two-phased method for the detection of evasive network attacks which exploit or pretend to be common legal encryption services in order to escape security inspection.Malicious communications which camouflage themselves as legal encryption application are identified in the SSL'session structure verification phase firstly,and then by serverside X.509 certificate based anomaly detection,suspicious attack behaviors are further distinguished effectively.Experiment results show that our method is very useful for detecting the network activities of certain unknown threats or new malwares.Besides,the proposed method can be applied to other similar services easily.
基金supported by the National 973 Basic Research Program of China under grant No.2014CB340600the National Natural Science Foundation of China under grant No.61370230 and No.61662022+1 种基金Program for New Century Excellent Talents in University Under grant NCET-13-0241Natural Science Foundation of Huhei Province under Grant No.2016CFB371
文摘In traditional framework,mandatory access control(MAC) system and malicious software are run in kernel mode. Malicious software can stop MAC systems to be started and make it do invalid. This problem cannot be solved under the traditional framework if the operating system(OS) is comprised since malwares are running in ring 0 level. In this paper,we propose a novel way to use hypervisors to protect kernel integrity and the access control system in commodity operating systems. We separate the access control system into three parts: policy management(PM),security server(SS) and policy enforcement(PE). Policy management and the security server reside in the security domain to protect them against malware and the isolation feather of the hypervisor can protect them from attacks. We add an access vector cache(AVC) between SS and PE in the guest OS,in order to speed up communication between the guest OS and the security domain. The policy enforcement module is retained in the guest OS for performance. The security of AVC and PE can be ensured by using a memory protection mechanism. The goal of protecting the OS kernel is to ensure the security of the execution path. We implementthe system by a modified Xen hypervisor. The result shows that we can secure the security of the access control system in the guest OS with no overhead compared with modules in the latter. Our system offers a centralized security policy for virtual domains in virtual machine environments.Keywords: hypervisor; virtualization; memo-
