This paper deeply discusses the design method of the File Transfer System(FTS)which is based on the File Transfer, Access and Management(FTAM) protocol standard, and probes into the construction principle of the Virtu...This paper deeply discusses the design method of the File Transfer System(FTS)which is based on the File Transfer, Access and Management(FTAM) protocol standard, and probes into the construction principle of the Virtual Filestore(VFS). Finally we introduce the implementation and the key technology of the FTS system.展开更多
When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing th...When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing the distribution of server-like nodes' upstream-bandwidth among their concurrent transfers. A sufficient condition for the service rate, what a receiver obtains for downloading a file, to asymptotically be uniform is presented. On the aggregate service rate for transferring a file in a system, a sufficient condition for it to asymptotically follow a Zipf distribution is presented. These asymptotic equalities are both in the mean square sense. These analyses and the sufficient conditions provide a mathematic base for modeling file transfer processes in peer-to-peer file sharing systems.展开更多
A file transfer algorithm based on ADP （autonomous decentrafized protocol） was proposed to solve the problem that the ADS （autonomous decentralized system） middleware （NeXUS/Drink） lacks of file transfer functio...A file transfer algorithm based on ADP （autonomous decentrafized protocol） was proposed to solve the problem that the ADS （autonomous decentralized system） middleware （NeXUS/Drink） lacks of file transfer functions for Windows. The algorithm realizes the peer-to-peer file transfer, one-to-N inquiry/multi-response file transfer and one-to-N file distribution in the same data field based on communication patterns provided by the ADP. The peer-to-peer file transfer is implemented through a peer-to-peer communication path, one-to-N inquiry/multi-response file transfer and one-to-N file distribution are implemented through multicast communication. In this algorithm, a file to be transferred is named with a GUID （global unique identification）, every data packet is marked with a sequence number, and file-receiving in parallel is implemented by caching DPOs（data processing objects） and multi-thread technologies. The algorithm is applied in a simulation system of the decentralized control platform, and the test results and long time stable tanning prove the feasibility of the algorithm.展开更多
The authors, first of all, discuss the importance of implementing application layer protocol ofLAN. A study in this area is required in order to speed up its practical uses as well as further de-velopment in the direc...The authors, first of all, discuss the importance of implementing application layer protocol ofLAN. A study in this area is required in order to speed up its practical uses as well as further de-velopment in the direction. The present paper is a brief report of the authors’ design methodologyand development of File Transfer Access and Management in reference to the ISO / OSI Moduleand implementation of its service protocol in a LAN,展开更多
This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktis...This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktispan the smallestone. Three situations with展开更多
白盒模型下密码分析者被授权可以完全访问加密软件实现的中间过程.为了解决现有白盒密码通信中密钥生成方式固定、安全性不足的问题,构造了动态白盒库,设计了改进的SM4动态白盒密码算法WBDL(white-box SM4 algorithm based on dynamic w...白盒模型下密码分析者被授权可以完全访问加密软件实现的中间过程.为了解决现有白盒密码通信中密钥生成方式固定、安全性不足的问题,构造了动态白盒库,设计了改进的SM4动态白盒密码算法WBDL(white-box SM4 algorithm based on dynamic white-box library).算法设计中应用新的查找表理论,构造了非固定的动态白盒库,把SM4算法的轮函数分割成三个阶段,再进行置乱编码,然后将密钥信息隐藏在第二阶段的查找表中以保护密钥.以设计的WBDL算法为基础构造了白盒加密通信软件系统,能够完成即时通讯、文件加解密、定期更换加密密钥等功能,可以在数据安全传输过程中实现对文件及密钥的有效保护.测试结果表明算法平均加密速率为0.273×10^(−3) Gbps,平均解密速率为0.234×10^(−3) Gbps,占用空间仅为尚-白盒算法的3%,但运算效率却更高;所设计的白盒加密通信软件对文件进行加解密的速度相近,平均值约为0.26 Mbps;文件加密传输速度均值为0.95 Mbps;软件系统的平均响应时间为425 ms.展开更多
明确了计算机网络业务可靠性的概念,着重强调了业务不同,可靠性不同.基于网络业务可靠性分层指数的评价法,讨论了局域网FTP(File Transfer Protocol)业务可靠性的试验流程,给出了一种新的测评方法,并对实验室计算机局域网进行了试验测评...明确了计算机网络业务可靠性的概念,着重强调了业务不同,可靠性不同.基于网络业务可靠性分层指数的评价法,讨论了局域网FTP(File Transfer Protocol)业务可靠性的试验流程,给出了一种新的测评方法,并对实验室计算机局域网进行了试验测评.在案例中,针对局域网中的FTP业务可靠性试验中存在的问题,设计了一个基于Windows批处理.bat脚本程序的FTP数据包发生器作为流量生成器,并研究了基于网络嗅探器Sniffer Pro的业务可靠性试验数据收集方法,给出了试验的具体步骤和试验结果.案例中得到的统计数据与实际网络状况相符.由此,该可靠性试验与评估技术得到了实证,同时也为其他业务的可靠性研究提供了参考.展开更多
文摘This paper deeply discusses the design method of the File Transfer System(FTS)which is based on the File Transfer, Access and Management(FTAM) protocol standard, and probes into the construction principle of the Virtual Filestore(VFS). Finally we introduce the implementation and the key technology of the FTS system.
基金National High Technology Research and Development Program of China (No.2007AA01Z457)Shanghai Science and Technology Development Fundation,China(No.07QA14033)
文摘When examining the file transfer performance in a peer-to-peer file sharing system, a fundamental problem is how to describe the service rate for a file transfer. In this paper, the problem is examined by analyzing the distribution of server-like nodes' upstream-bandwidth among their concurrent transfers. A sufficient condition for the service rate, what a receiver obtains for downloading a file, to asymptotically be uniform is presented. On the aggregate service rate for transferring a file in a system, a sufficient condition for it to asymptotically follow a Zipf distribution is presented. These asymptotic equalities are both in the mean square sense. These analyses and the sufficient conditions provide a mathematic base for modeling file transfer processes in peer-to-peer file sharing systems.
基金The National Innovation Fund(No.00C262251211336)the Project of State Key Laboratory of Rail Traffic Control and Safety, Beijing Jiaotong University(No.SKL2007K001)
文摘A file transfer algorithm based on ADP （autonomous decentrafized protocol） was proposed to solve the problem that the ADS （autonomous decentralized system） middleware （NeXUS/Drink） lacks of file transfer functions for Windows. The algorithm realizes the peer-to-peer file transfer, one-to-N inquiry/multi-response file transfer and one-to-N file distribution in the same data field based on communication patterns provided by the ADP. The peer-to-peer file transfer is implemented through a peer-to-peer communication path, one-to-N inquiry/multi-response file transfer and one-to-N file distribution are implemented through multicast communication. In this algorithm, a file to be transferred is named with a GUID （global unique identification）, every data packet is marked with a sequence number, and file-receiving in parallel is implemented by caching DPOs（data processing objects） and multi-thread technologies. The algorithm is applied in a simulation system of the decentralized control platform, and the test results and long time stable tanning prove the feasibility of the algorithm.
文摘The authors, first of all, discuss the importance of implementing application layer protocol ofLAN. A study in this area is required in order to speed up its practical uses as well as further de-velopment in the direction. The present paper is a brief report of the authors’ design methodologyand development of File Transfer Access and Management in reference to the ISO / OSI Moduleand implementation of its service protocol in a LAN,
文摘This project was designated as Meritorious of Mathematical Contest inModeling (MCM'94). We have been required tu solve a problem of findins thebest schedule of a file transfer network in order to niake the niaktispan the smallestone. Three situations with
文摘明确了计算机网络业务可靠性的概念,着重强调了业务不同,可靠性不同.基于网络业务可靠性分层指数的评价法,讨论了局域网FTP(File Transfer Protocol)业务可靠性的试验流程,给出了一种新的测评方法,并对实验室计算机局域网进行了试验测评.在案例中,针对局域网中的FTP业务可靠性试验中存在的问题,设计了一个基于Windows批处理.bat脚本程序的FTP数据包发生器作为流量生成器,并研究了基于网络嗅探器Sniffer Pro的业务可靠性试验数据收集方法,给出了试验的具体步骤和试验结果.案例中得到的统计数据与实际网络状况相符.由此,该可靠性试验与评估技术得到了实证,同时也为其他业务的可靠性研究提供了参考.
