The effect of correlated fading reduces the performance gain in multi-antenna communications. Diversity combining is a well-known technique to reduce the effect of correlation. But still, it is an open problem to quan...The effect of correlated fading reduces the performance gain in multi-antenna communications. Diversity combining is a well-known technique to reduce the effect of correlation. But still, it is an open problem to quantify as the diversity scheme is more efficient in enhancing the security of cellular multicast network mitigating the effects of correlation. Motivated by this issue, this paper considers a secure wireless multicasting scenario through correlated cellular networks in the presence of multiple eavesdroppers. The selection combining (SC) and switch and stay combining (SSC) techniques are considered in dual arbitrarily correlated Nakagami-m fading channels. The closed-form analytical expressions for the probability of non-zero secrecy multicast capacity and the secure outage probability for multicasting are derived to understand the insight into the effects of correlation on the SC and SSC diversity schemes and to quantify which diversity scheme is more efficient in enhancing the security of correlated multicast networks. The results show that, although the diversity gain reduces the effect of correlation, the diversity gain provided by the SC diversity scheme is more significant in mitigating the effect of correlation compared to the SSC diversity scheme. Due to the selection mechanism of SC diversity, it is more sensitive to the change of SNR of the eavesdropper’s channel compared to the case of the SSC diversity scheme.展开更多
A GF(p) elliptic curve cryptographic coprocessor is proposed and implemented on Field Programmable Gate Array (FPGA). The focus of the coprocessor is on the most critical, complicated and time-consuming point multipli...A GF(p) elliptic curve cryptographic coprocessor is proposed and implemented on Field Programmable Gate Array (FPGA). The focus of the coprocessor is on the most critical, complicated and time-consuming point multiplications. The technique of coordinates conversion and fast multiplication algorithm of two large integers are utilized to avoid frequent inversions and to accelerate the field multiplications used in point multiplications. The characteristic of hardware parallelism is considered in the implementation of point multiplications. The coprocessor implemented on XILINX XC2V3000 computes a point multiplication for an arbitrary point on a curve defined over GF(2192?264?1) with the frequency of 10 MHz in 4.40 ms in the average case and 5.74 ms in the worst case. At the same circumstance, the coprocessor implemented on XILINX XC2V4000 takes 2.2 ms in the average case and 2.88 ms in the worst case.展开更多
简要介绍了UPnP(Universal Plug and Play)网络协议的体系结构,工作过程;并介绍了UPnP网络安全规约,分析了UPnP网络安全规约可能存在的问题;提出符合UPnP规范同时兼容UPnP安全规约的一套SC(SecurityConsole)管理方案,方案能较好的保证U...简要介绍了UPnP(Universal Plug and Play)网络协议的体系结构,工作过程;并介绍了UPnP网络安全规约,分析了UPnP网络安全规约可能存在的问题;提出符合UPnP规范同时兼容UPnP安全规约的一套SC(SecurityConsole)管理方案,方案能较好的保证UPnP网络中SC自身的安全和解决SC失效后带来的几个问题;并详细介绍方案的组成部分,工作过程。展开更多
为明确42%吡氟酰草胺悬浮剂对春小麦田一年生阔叶杂草防除效果及对春小麦的安全性,本研究采用茎叶喷雾法进行田间药效试验。结果表明,42%吡氟酰草胺悬浮剂使用量为283.50 g a.i./hm^(2)时,药后20 d对杂草株防效为74.13%;药后40 d对杂草...为明确42%吡氟酰草胺悬浮剂对春小麦田一年生阔叶杂草防除效果及对春小麦的安全性,本研究采用茎叶喷雾法进行田间药效试验。结果表明,42%吡氟酰草胺悬浮剂使用量为283.50 g a.i./hm^(2)时,药后20 d对杂草株防效为74.13%;药后40 d对杂草株防效为80.24%,鲜重防效为88.33%,对主要杂草密花香薷、野油菜、荞麦蔓鲜重防效达80%以上,对春小麦安全。展开更多
文摘The effect of correlated fading reduces the performance gain in multi-antenna communications. Diversity combining is a well-known technique to reduce the effect of correlation. But still, it is an open problem to quantify as the diversity scheme is more efficient in enhancing the security of cellular multicast network mitigating the effects of correlation. Motivated by this issue, this paper considers a secure wireless multicasting scenario through correlated cellular networks in the presence of multiple eavesdroppers. The selection combining (SC) and switch and stay combining (SSC) techniques are considered in dual arbitrarily correlated Nakagami-m fading channels. The closed-form analytical expressions for the probability of non-zero secrecy multicast capacity and the secure outage probability for multicasting are derived to understand the insight into the effects of correlation on the SC and SSC diversity schemes and to quantify which diversity scheme is more efficient in enhancing the security of correlated multicast networks. The results show that, although the diversity gain reduces the effect of correlation, the diversity gain provided by the SC diversity scheme is more significant in mitigating the effect of correlation compared to the SSC diversity scheme. Due to the selection mechanism of SC diversity, it is more sensitive to the change of SNR of the eavesdropper’s channel compared to the case of the SSC diversity scheme.
基金Supported by the National Natural Science Foun dation of China ( 69973034 ) and the National High TechnologyResearch and Development Program of China (2002AA141050)
文摘A GF(p) elliptic curve cryptographic coprocessor is proposed and implemented on Field Programmable Gate Array (FPGA). The focus of the coprocessor is on the most critical, complicated and time-consuming point multiplications. The technique of coordinates conversion and fast multiplication algorithm of two large integers are utilized to avoid frequent inversions and to accelerate the field multiplications used in point multiplications. The characteristic of hardware parallelism is considered in the implementation of point multiplications. The coprocessor implemented on XILINX XC2V3000 computes a point multiplication for an arbitrary point on a curve defined over GF(2192?264?1) with the frequency of 10 MHz in 4.40 ms in the average case and 5.74 ms in the worst case. At the same circumstance, the coprocessor implemented on XILINX XC2V4000 takes 2.2 ms in the average case and 2.88 ms in the worst case.
文摘简要介绍了UPnP(Universal Plug and Play)网络协议的体系结构,工作过程;并介绍了UPnP网络安全规约,分析了UPnP网络安全规约可能存在的问题;提出符合UPnP规范同时兼容UPnP安全规约的一套SC(SecurityConsole)管理方案,方案能较好的保证UPnP网络中SC自身的安全和解决SC失效后带来的几个问题;并详细介绍方案的组成部分,工作过程。
文摘为明确42%吡氟酰草胺悬浮剂对春小麦田一年生阔叶杂草防除效果及对春小麦的安全性,本研究采用茎叶喷雾法进行田间药效试验。结果表明,42%吡氟酰草胺悬浮剂使用量为283.50 g a.i./hm^(2)时,药后20 d对杂草株防效为74.13%;药后40 d对杂草株防效为80.24%,鲜重防效为88.33%,对主要杂草密花香薷、野油菜、荞麦蔓鲜重防效达80%以上,对春小麦安全。
