基于贝叶斯攻击图的SDN安全预测方法

现有研究者采用威胁建模和安全分析系统的方法评估和预测软件定义网络（software defined network, SDN）安全威胁,但该方法未考虑SDN控制器的漏洞利用概率以及设备在网络中的位置,安全评估不准确。针对以上问题,根据设备漏洞利用概率和设备关键度结合PageRank算法,设计了一种计算SDN中各设备重要性的算法;根据SDN攻击图和贝叶斯理论设计了一种度量设备被攻击成功概率的方法。在此基础上设计了一种基于贝叶斯攻击图的SDN安全预测算法,预测攻击者的攻击路径。实验结果显示,该方法能够准确预测攻击者的攻击路径,为安全防御提供更准确的依据。     

Attack path prediction method based on causal knowledge net

The existing attack path prediction methods can not accurately reflect the variation of the following attack path caused by the capability of the attacker.Accordingly an attack path prediction method based on causal knowledge net was presented.The proposed method detected the current attack actions by mapping the alarm sets to the causal knowledge net.By analyzing the attack actions,the capability grade of the attacker was inferred,according to which adjust the probability knowledge distribution dynamically.With the improved Dijkstra algorithm,the most possible attack path was computed.The experiments results indicate that the proposed method is suitable for a real network confrontation environment.Besides,the method can enhance the accuracy of attack path prediction.     

Research on switch migration method based on minimum cost path

In order to protect the controller,especially the controller in backbone network,from security threats and attacks,improve the security of the software-defined network (SDN) control plane,a switch migration algorithm based on minimum cost path was proposed.A load prediction module was added to the migration model,which executed a controller load prediction algorithm to obtain a load prediction matrix,and then a migration-target controller set was determined according to the load prediction matrix.The improved Dijkstra algorithm was used to determine the minimum cost path.According to the load state of the controller and the traffic priority of the switch to be migrated,the optimal migration switch set was determined.The problem of isolated nodes was solved that may occur during the migration process.The experimental results show that the migration timing of the algorithm is more reasonable,the selection of the migration controller and the target controller is more reasonable,the load balancing of the control plane is realized,the number of migrations and cost are reduced,and the performance of the controller is improved.     

传感器网络基于DTW的多小波压缩算法

提出传感器网络环境下基于DTW的多小波数据压缩算法。首先研究汇聚节点中异步数据点—点对的对应关系,设计迭代算法求出具有最大相关性的DTW弯曲路径。接着提出最佳匹配点选择算法,通过DTW弯曲路径中一对一数据点—点对来预测异步数据向量间的函数关系,获取最佳匹配点,得到具有最大相关性的传感数据矩阵。然后设计多小波变换,利用传感数据矩阵的相关性来压缩数据,同时解决数据矩阵的行列不对称问题。实验结果表明,所提出的算法在能量聚集比、重构精度和运行时间等压缩性能指标上优于经典的分布式小波压缩算法。     

层次分析法在ZigBee网络语音通信中的应用研究

在自组织网络语音通信中,针对音频传输中存在的延时、丢包等主要问题,在ZigBee网络路由的基础上建立层次分析法评价模型,设计了一种音频传输路由算法AHP-RP。通过分析路径链路质量、音频负载值、路径存活时间和路径长度等因素对音频质量的影响,构建以网络的4个因素为因子的比较矩阵,选择最优传输路径。仿真及实际通信平台验证表明,该算法能有效地适应网络状态,明显改善了语音通话质量。     

基于攻击图的渗透测试方法

传统的病毒检测系统、网络防火墙、入侵检测系统等技术只能够检测出已知的大部分威胁,但却无法检测出网络中存在的潜在的问题。为此,文中提出了一种基于攻击图的渗透测试方法。首先,考虑到攻击持续时间、攻击类型等方面因素,对现有的攻击图方法进行改进,提出一种新的攻击图技术;其次,基于实际应用,从攻击的路径、时间、代价、方式等方面综合考虑,提出攻击图最优攻击路径选择策略;最后,设计基于攻击图的渗透测试模型,并进行了试验测试。测试结果表明,该渗透测试算法能够更好的模拟现实世界中的真实攻击。同时能够对当前设备的安全状态进行评估,可以在实际渗透测试中进行应用。     

E‐TDGO: An encrypted trust‐based dolphin glowworm optimization for secure routing in mobile ad hoc network

Mobile ad hoc networks (MANETs) are independent networks, where mobile nodes communicate with other nodes through wireless links by multihop transmission. Security is still an issue to be fixed in MANETs. Hence, a routing protocol named encrypted trust‐based dolphin glowworm optimization (DGO) (E‐TDGO) is designed using Advanced Encryption Standard‐128 (AES‐128) and trust‐based optimization model for secure routing in MANET. The proposed E‐TDGO protocol includes three phases, namely, k‐path discovery, optimal path selection, and communication. At first, k paths are discovered based on the distance and the trust level of the nodes. From the k paths discovered, the optimal path is selected using a novel algorithm, DGO, which is developed by combining glowworm swarm optimization (GSO) algorithm and dolphin echolocation algorithm (DEA). Once the optimal path is selected, communication begins in the network such that E‐TDGO protocol ensures security. The routing messages are encrypted using AES‐128 with shared code and key to offer security. The experimental results show that the proposed E‐TDGO could attain throughput of 0.11, delay of 0.01 second, packet drop of 0.44, and detection rate of 0.99, at the maximum number of rounds considered in the network of 75 nodes with attack consideration.     

基于有限条件攻击的安全测试方法

在网络战环境下,为了提高通信网络的抗攻击能力,需要对通信网络的安全性进行较全面的攻击测试。文中提出了基于有限条件攻击的安全测试方法,并设计了有限制条件攻击测试模型和算法。有限制条件攻击测试模型由攻击、目标、响应、条件四部分构成。基于该方法设计并实现了相应的原型攻击测试系统,并对GSM等无线网络进行了攻击测试,表明该方法可行、有效。     

Optimization design of structure invulnerability for air defense multiple sensor network

To improve the invulnerability of air defense multiple sensor network,its topological structure optimization model was established with the constraint of network node’s degree and network connectivity,combined with the total sum of network’s natural connectivity for attack strategy as object function.Then,solving steps of the model were designed based on improve artificial immune algorithm to solve the model.In order to improve the searching efficiency of the algorithm,new steps of immune review and antibody correction were designed to increase the number of effective antibodies in population.Simulation and results prove rationality of the model and feasibility of the modified artificial immune algorithm,optimization based on the index of total natural connectivity for attack strategy can improve the invulnerability of air defense multiple sensor network.     

基于云计算的经济预测系统研究

目前普遍使用的经济预测系统在运行时是由政府决策者自行选择预测模型,而不能够由系统自动筛选最优预测模型,这使得最后得到的预测结果不是最优的.同时,现有的预测系统运行于单台小型机上,随着金融数据的不断增多以及预测模型的不断复杂,这势必将会超过小型机的工作负荷,大大降低系统的计算分析能力,增加等待时间.因此,就需要充分利用本...     

Wireless sensor networks based on modular arithmetic

The authors propose the method for data coding in wireless sensor networks (WSN) based on the transformation of the residue number system and multipath routing. It enables to utilize efficiently the bandwidth of communication channels as well as reduce message delivery time. It is explored the ant algorithm to search an optimal route of data transmission in the wireless sensor network. There is introduced a limitation for the communication radius of the wireless unit that shorts a number of the search decision modes and improves the accuracy of the wireless network simulation. The correspondent software is designed, it allowes exploring the dynamics of finding the optimal transmission path in WSN in case of different algorithm settings, and exploring the impact of the elite ants on the accuracy of the found path.     

一种无线多媒体传感器网络路径最优路由算法

介绍了无线多媒体传感网络(WMSN)路由的设计原则与策略,描述了路径最优的基本原理,最后从最优路径的选择、信息转发策略、节点能量消耗3个方面考虑,设计出路径最优路由算法。该算法与蚁群算法进行比较,实验结果表明,该算法在节点能量消耗、信息传送速度上都优于蚁群算法,尤其传速率提高了30%左右。     

神经网络方法在降雨去极化效应预报中的应用

利用神经网络中的ＢＰ算法，通过在已知的传播路径上降雨同极化衰减ＣＰＡ来预算降雨去极化分辨率ＸＰＤ，且将计算结果与其他算法进行了对比。本文的工作是神经网络方法在建立电波大气传输效应预报模型应用中的有益尝试。     

物联网感知层多路径传输策略研究

多路径数据传输是无线传感器网络亟需解决的一个关键问题.本文针对节点故障、链路失效和外界干扰影响网络稳定性和可靠性,提出一种基于混合蛙跳算法的无线传感器网络多路径传输策略.首先我们详细介绍了蛙跳算法及其原理,之后我们将其应用到无线传感器网络多路径传输策略之中,接着运用混合蛙跳算法对传感网络节点其进行更新、划分、重组以便选择出最优节点建立传输最优路径,提高网络的稳定性和可靠性.通过算法仿真与结果对比提出的算法与AODV、粒子群PSO算法相比,在网络能耗、传输时延、丢包率、连通率和可靠度等方面都具有较好的性能.其中网络能耗比AODV、PSO算法降低了62.5％和35.8％.     

Network moving target defense technique based on optimal forwarding path migration

Moving target defense is a revolutionary technology which changes the situation of attack and defense.How to effectively achieve forwarding path mutation is one of the hotspot in this field.Since existing mechanisms are blindness and lack of constraints in the process of mutation,it is hard to maximize mutation defense benefit under the condition of good network quality of services.A novel of network moving target defense technique based on optimal forwarding path migration was proposed.Satisfiability modulo theory was adopted to formally describe the mutation constraints,so as to prevent transient problem.Optimization combination between routing path and mutation period was chosen by using optimal routing path generation method based on security capacity matrix so as to maximum defense benefit.Theoretical and experimental analysis show the defense cost and benefit in resisting passive sniffing attacks.The capability of achieving maximum defense benefit under the condition of ensuring network quality of service is proved.     

Optimal strategy selection method for moving target defense based on signaling game

To solve the problem of the optimal strategy selection for moving target defense,the defense strategy was defined formally,the defense principle from the perspective of attack surface shifting and exploration surface enlarging was taken into account.Then,network attack-defense behaviors were analyzed from the sight of dynamic confrontation and bounded information.According to the analysis of attack-defense game types and confrontation process,the moving target defense model based on signaling game was constructed.Meanwhile,the method to quantify strategies was improved and the solution of perfect Bayesian equilibrium was proposed.Furthermore,the optimal defense strategy selection algorithm was designed by the equilibrium analysis.Finally,the simulation demonstrates the effectiveness and feasibility of the proposed optimal strategy and selection method.     

基于强化学习的定向无线通信网络抗干扰资源调度算法

为了在无线网络中进行高效的链路资源调度、减小网络干扰、提高网络容量,提出了一种利用回溯天线并考虑干扰环境的链路资源分布式智能调度算法.首先,结合通信的路径损耗模型设计卷积核,对节点密度矩阵进行卷积来衡量干扰链路强度,从而避免对所有干扰链路进行信道估计产生巨大的计算代价;然后,结合强化学习的思想设计了与通信环境交互的链路调度学习模型,每个链路利用神经网络进行独立的训练,将训练所得的决策结果反馈到环境中进行状态更新,模型在不断更新的环境中迭代来学习最优的调度策略.该方法能分布式的运行,可有效衡量无线网络中的链路干扰强度,结合衡量结果进行高效的链路资源分布式调度,从而最大化网络容量.仿真结果验证了该调度算法无论是在算法迭代收敛还是网络容量性能上都能很好地逼近全局的调度算法,达到全局算法最优结果的92%~100%.     

基于国家电波观测站网信号的短波机动用户位置认知方法

短波通信中频率选择是提高通信质量的必要手段,但短波机动用户却难以获取选频链路计算需要的位置信息. 文中设计了一种随时可利用多站信号进行机动终端位置认知的方法. 逆向应用时差定位原理,通过机动终端接收到的三个站点信号的两两信号时延差与虚路径差成正比,形成两条双曲线,交点就是机动用户的位置. 算法的关键是利用国家电波观测站网常态化发射的探测信号,同时设计了基于网格化预测时差与实测时差之间误差的位置概率函数,将定位问题转化为概率选择问题. 仿真分析和实测数据都验证了算法的可行性. 最后讨论了几种算法的改进策略,有望尽快实现工程应用.     

Construction mechanism for service path over reconfigurable service-centric network

In order to enhance the flexible and intelligent network's service ability,a novel architecture called recon-figurable service-centric network (ReSCNet) was proposed which decomposed traditional network capabilities and ser-vices into fine-grained network functional unit.Then based on service routing matrix algorithm to orchestrate and deploy atomic service flexibly,a service path was built which possess smaller cost,lower time delay,higher degree of load bal-ance and higher reliability.Finally,the performance of service routing matrix algorithm was evaluated on the innovation experiment platform NetFPGA-10G.The simulation results show that the algorithm has a better performance and can cus-tomize an optimal service path for users while meet the specific functions and performance constraints.     

单机多目标攻击的最佳发射点选择算法研究

选择最佳发射点就是以预期攻击效果最佳化来确定开火时机,这对多目标攻击武器系统具有重要意义。提出在攻击航线与攻击区的相交段上,以综合杀伤概率最大化原则来选择多目标攻击的最佳发射点。在阐述研究思想和步骤的基础上,设计了多目标攻击最佳发射点选择算法,并给出了仿真算例与结果。