Research on Multi-Layer Distributed HF Radio Network Structure

High frequency（HF）transmission is an important communication techniques.However,conven-tional point-to-point transmission can be easily destroyed,which limits its utilization in practice.HF networking communication has the capability against demolishment.The network structure is one of the key factors for HF networking communication.In this paper,a novel analysis method of the network connectedness based on the eigenvalue is derived,and a multi-layer distributed HF radio network structure is proposed.Both the theore-tical analysis and the computer simulation results verify that the application of the proposed network structure in the HF radio communication can improve the anti-demolishment ability of the HF network efficiently.     

Design of a hybrid switching architecture for avionic WDM platforms

A novel hybrid switching architecture using optical circuit switching for intra-subnet communication and fiber channel（FC）for inter-subnet communication is proposed.The proposed scheme utilizes small-size arrayed waveguide grating routers（AWGRs）and legacy FC switches to construct the large-scale avionic network,thus has the potential of the lower latency,the satisfactory network bandwidth and the lower power consumption.The simulation results verify that the proposed architecture outperforms FC switched architecture in terms of real time performance and power consumption.     

MIIT Issued Guidance on Strengthening Cybersecurity Work in the Telecommunications and Internet Industries

1.Deepening the network infrastructure and business systems security. Seriously implement the ＂communications network security management approach＂ （MIIT Order No. 11） and communication network security series of standards, do a good job in grading for the record, strictly implement protective measures, regularly carry out compliance evaluation and risk assessment in a timely manner in order to eliminate safety hazards. Strengthen network and information asset management, comprehensively sort the list of key devices,     

Study of Intrusion Detection Systems

Modern network systems have much trouble in security vulnerabilities such as buffer overflow, bugs in Microsoft Internet, sensor network routing protocol too simple, security flaws of applications, and operating systems. Moreover, wireless devices such as smart phones, personal digital assistants （PDAs）, and sensors have become economically feasible because of technological advances in wireless communication and manufacturing of small and low-cost sensors. There are typologies of vulnerabilities to be exploited in these devices. In order to improve securities, many mechanisms are adopted, including authentication, cryptography, access control, and intrusion detection systems （IDS）. In general, intrusion detection techniques can be categorized into two groups： misuse detection and anomaly detection. The misuse detection systems use patterns of weB-known attacks or weak spots of the systems to identify intrusions. The weakness of misuse detection systems is unable to detect any future （unknown） intrusion until corresponding attack signatures are intruded into the signature database. Anomaly detection methods try to determine whether the deviation is from the established normal usage patterns or not. The critical success of anomaly detection relies on the model of normal behaviors.     

A RISK ASSESSMENT METHOD OF THE WIRELESS NETWORK SECURITY

The core of network security is the risk assessment. In this letter, a risk assessment method is introduced to estimate the wireless network security. The method, which combines Analytic Hierarchy Process （AHP） method and fuzzy logical method, is applied to the risk assessment. Fuzzy logical method is applied to judge the important degree of each factor in the aspects of the probability, the influence and the uncontrollability, not to directly judge the important degree itself. The risk assessment is carved up 3 layers applying AHP method, the sort weight of the third layer is calculated by fuzzy logical method. Finally, the important degree is calculated by AHP method. By comparing the important degree of each factor, the risk which can be controlled by taking measures is known. The study of the case shows that the method can be easily used to the risk assessment of the wireless network security and its results conform to the actual situation.     

The Application of NPs in WCDMA Systems

Recent efforts to add new services to the wide-band code division multiple accesses （WCDMA） system have increased interest in network processor （NP）-based routers that are easy to extend and evolve. In this paper, an application of NPs in routing engine module （REM） of radio network controller （RNC） in WCDMA system is proposed. The measuring results show that NPs have good performance and efficiency in routing traffic of the communication network and the simulation verifies the fast forwarding function of NPs.     

A New Anonymity Model for Privacy-Preserving Data Publishing

Privacy-preserving data publishing （PPDP） is one of the hot issues in the field of the network security. The existing PPDP technique cannot deal with generality attacks, which explicitly contain the sensitivity attack and the similarity attack. This paper proposes a novel model, （w,γ, k）-anonymity, to avoid generality attacks on both cases of numeric and categorical attributes. We show that the optimal （w, γ, k）-anonymity problem is NP-hard and conduct the Top-down Local recoding （TDL） algorithm to implement the model. Our experiments validate the improvement of our model with real data.     

A novel BTC decoding algorithm based on the genetic algorithm in optical communication systems

Combining the advantages of both the genetic algorithm （GA） and the chase decoding algorithm, a novel improved decoding algorithm of the block turbo code （BTC） with lower computation complexity and more rapid decoding speed is proposed in order to meet the developing demands of optical communication systems. Compared with the traditional chase decoding algorithm, the computation complexity can be reduced and the decoding speed can be accelerated by applying the novel algorithm. The simulation results show that the net coding gain （NCG） of the novel BTC decoding algorithm is 1.1 dB more than that of the traditional chase decoding algorithm at the bit error rate （BER） of 10^-6. Therefore, the novel decoding algorithm has better decoding correction-error performance and is suitable for the BTC in optical communication systems.     

Reliability Evaluation of All-User Terminals in LEO Satellite Communication Network Based on Modular Reduction

LEO satellite communication network has a large number of satellites distributed in low orbits,which leads to multiple coverage of many areas on the ground.It is hard work to describe and evaluate the reliability of LEO satellite communication network.To solve this problem,the reliability of all-user terminals in LEO satellite communication network is defined,and the corresponding reliability evaluation method is proposed in the paper.Due to the large scale of the interstellar network,a modular reduction algorithm using the modular network instead of the original network for state decomposition is proposed in this paper.Case study shows that the calculation time of the proposed method is equivalent to 6.28%of the original state space decomposition algorithm.On this basis,the reliability of LEO satellite communication network is further analyzed.It is found that the reliability of LEO satellite network was more sensitive to the reliability of Inter-Satellite link and the satisfaction of global coverage in the early stage,and it is more sensitive to the reliability of the satellite in the later stage.The satellite-ground link has a relatively constant impact on of LEO satellite network.     

Wireless Heterogeneous Network Architecture under Non-Uniform Information Density Conditions

Capacity of the mobile communication system is predicted to increase 1000 times in the next ten years with the rapid growth of network traffic. Capacity growth stems from three dimensions, the revolution of wireless network architecture, and the exploitation of new spectrum and the invention of new wireless technology with higher efficiency. The contribution scale of the three dimensions is 64：1：1. The architec-ture of wireless network lays the foundation of mobile communication systems and involves technologies of multi-field. It＇s always been the focus of international competitions. Supported by national project, Beijing University of Posts and Telecommunications （BUPT） and Zhongxing Telecommunications Equipment （ZTE） Corporation worked together to investigate on this issue.     

一种基于单电子隧穿结和MOS晶体管的混合随机数发生器

提出了一种新颖的单电子随机数发生器(RNG).该随机数发生器由多个单电子隧穿结(MTJ)以及单电子晶体管(SET)/MOS管混合输出电路组成.MTJ被用于实现一个高频率的振荡器.它利用了电子隧穿的物理随机性得到了很大的振荡频率漂移.SET/MOS管输出电路放大并输出MTJ振荡器的输出信号.该信号经过一个低频信号采样后,产生随机数序列.所提出的随机数发生器使用简单的电路结构产生了高质量的随机数序列.它具有简单的结构,输出随机数的速度可以高达1GHz.同时,该电路还具有带负载能力以及很低的功耗.这种新颖的随机数发生器对未来的密码和通讯系统具有一定的应用前景.     

一种基于单电子隧穿结和MOS晶体管的混合随机数发生器

提出了一种新颖的单电子随机数发生器(RNG).该随机数发生器由多个单电子隧穿结(MTJ)以及单电子晶体管(SET)/MOS管混合输出电路组成.MTJ被用于实现一个高频率的振荡器.它利用了电子隧穿的物理随机性得到了很大的振荡频率漂移.SET/MOS管输出电路放大并输出MTJ振荡器的输出信号.该信号经过一个低频信号采样后,产生随机数序列.所提出的随机数发生器使用简单的电路结构产生了高质量的随机数序列.它具有简单的结构,输出随机数的速度可以高达1GHz.同时,该电路还具有带负载能力以及很低的功耗.这种新颖的随机数发生器对未来的密码和通讯系统具有一定的应用前景.     

一种基于混沌的随机数发生器设计及其IC实现

在密码学、仿真学以及集成电路测试等许多领域 ,随机数起着重要的作用。在密码学中 ,通常要求所使用的随机数具有不可预测性。基于混沌现象 ,使用开关电容技术 ,用集成电路实现了一种硬件随机数发生器。测试结果表明 ,其产生的序列具有不可预测性 ,可以满足密码学的应用要求。     

WDM-PON中基于AWG的新型OVPN研究

在波分复用无源光网络(WDM-PON)中,提出了一种基于阵列波导光栅(AWG)的新型光虚拟专用网(OVPN)。OVPN采用环形结构,在不同光网络单元(ONU)之间使用波长通道直接通信,不仅保证了ONU之间通信的安全性,而且提高了网络生存性。分别从光功率损耗和系统误码率(BER)进行了数值分析,结果表明,本文结构不仅增加了通信的安全性,而且仅使用4个波长就能实现16个ONU的相互联接,从而节省了波长资源,且具有很强的抗串扰能力。     

Single-electron random-number generator (RNG) for highly secure ubiquitous computing applications

Since the security of all modern cryptographic techniques relies on unpredictable and irreproducible digital keys generated by random-number generators (RNGs), the realization of high-quality RNG is essential for secure communications. In this report, a new RNG, which utilizes single-electron phenomena, is proposed. A room-temperature operating silicon single-electron transistor (SET) having nearby an electron pocket is used as a high-quality, ultra-small RNG. In the proposed RNG, stochastic single-electron capture/emission processes to/from the electron pocket are detected with high sensitivity by the SET, and result in giant random telegraphic signals (GRTS) on the SET current. It is experimentally demonstrated that the single-electron RNG generates extremely high-quality random digital sequences at room temperature, in spite of its simple configuration. Because of its small-size and low-power properties, the single-electron RNG is promising as a key nanoelectronic device for future ubiquitous computing systems with highly secure mobile communication capabilities.     

一种新型稀疏Ad Hoc网络消息签名方案

针对稀疏Ad Hoc网络的易断易延时特性,采用基于身份的密码体制和椭圆曲线双线性对,提出一种新的稀疏Ad Hoc网络消息签名方案,并对方案的安全性和性能进行了分析。该方案可以解决第三方密钥托管带来的签名伪造问题,限制稀疏Ad Hoc网络中节点私钥泄密带来的伪造消息签名的影响,在保证安全性的前提下,有效减少密钥长度、签名长度与签名的计算量,降低了对网络通信带宽和节点存储、计算能力的要求,符合稀疏Ad Hoc网络的签名需求。     

车联网环境下无证书匿名认证方案

通过信息共享,车联网(IoV)为车辆提供各种应用,以提高道路安全和交通效率。然而,车辆之间的公开通信导致了车辆隐私泄露和各种攻击。因而,安全且保护隐私的信息共享方法是非常必要的,并且对车辆间通信的安全性和保密性提出了更高的要求,所以该文提出了一种支持批量验证的非线性对的无证书匿名认证方案。在该方案中,首先,采用无证书签名机制避免了证书管理和密钥托管问题;其次结合区域管理局生成的长期伪身份和自己生成的短期伪身份保证车辆的强匿名性和签名的新鲜性,避免路侧单元计算伪身份造成的身份泄露和时延;再次,采用无对的聚合签名提供批验证,减少车联网环境中路侧单元的计算量;最后,当发生恶意事件时,区域管理局可以追踪车辆的真实身份并由可信中心撤销该用户。安全性证明和分析表明,该方案具有高的安全性,并满足完整性、可追踪性、匿名性、可撤销性等安全要求。将该方案与现有的方案进行了比较,效率分析表明该方案更有效。     

多媒体通信中智能化媒体内同步机制

本文提出了一种智能化视频流量的预测和同步机制（ＩＦＳＭ）,它由ＢＰ神经网络流量预测器（ＢＰＮＮ）、输出缓冲区和基于模糊神经网络（ＦＮＮ）的输出速率决策器所组成。ＢＰＮＮ采用一种在线训练的ＢＰ神经网络预测在将来的一定时间间隔（ＦＩ）内的平均分组速率,ＦＮＮ决策器根据预测的流量特性和缓冲区中的分组数动态地调节下一个分组输出的时间。仿真结果表明：与窗口机制相比,ＩＦＳＭ能够使视频流量取得较高的连续性和较低的时延,并且由于ＦＮＮ的学习能力,ＩＦＳＭ可以自适应地调节相应参数以满足不同的服务质量的要求。     

Very High-Speed True Random Noise Generator

In this work an original CMOS implementation of a discrete-time deterministic-chaos algorithm for random bit generation is presented. The proposed circuit topology prevents the degradation of the generated-sequence statistical properties that can be caused by several factors, including the parameter spreading of the technological processes. Experimental results show that, with a final rate of 3 Mbit/s, the circuit is compliant with the most recent security requirements for cryptographic modules issued by the American National Institute of Standards and Technologies.     

一种分段线性映射的混沌随机数发生器特性研究

该文通过对确定性混沌演化本质的分析和对其系统状态空间的划分,使它转变为一个各态历经的信息源以用于设计随机数发生器。然后又分析了一种混沌的分段线性映射的特性,如:混沌吸引子与点吸引子,信源熵与冗余度以及混沌映射产生的序列的分布特性。此外,利用开关电容电路技术用TSMC 0.25μm CMOS数模混合工艺实现了此分段线性映射。测试结果表现出非常好的抗干扰性能。