A Reputation-Based AODV Protocol for Blackhole and Malfunction Nodes Detection and Avoidance

Enhancing the security of Wireless Sensor Networks(WSNs)improves the usability of their applications.Therefore,finding solutions to various attacks,such as the blackhole attack,is crucial for the success of WSN applications.This paper proposes an enhanced version of the AODV(Ad Hoc On-Demand Distance Vector)protocol capable of detecting blackholes and malfunctioning benign nodes in WSNs,thereby avoiding them when delivering packets.The proposed version employs a network-based reputation system to select the best and most secure path to a destination.To achieve this goal,the proposed version utilizes the Watchdogs/Pathrater mechanisms in AODV to gather and broadcast reputations to all network nodes to build the network-based reputation system.To minimize the network overhead of the proposed approach,the paper uses reputation aggregator nodes only for forwarding reputation tables.Moreover,to reduce the overhead of updating reputation tables,the paper proposes three mechanisms,which are the prompt broadcast,the regular broadcast,and the light broadcast approaches.The proposed enhanced version has been designed to perform effectively in dynamic environments such as mobile WSNs where nodes,including blackholes,move continuously,which is considered a challenge for other protocols.Using the proposed enhanced protocol,a node evaluates the security of different routes to a destination and can select the most secure routing path.The paper provides an algorithm that explains the proposed protocol in detail and demonstrates a case study that shows the operations of calculating and updating reputation values when nodes move across different zones.Furthermore,the paper discusses the proposed approach’s overhead analysis to prove the proposed enhancement’s correctness and applicability.

Avoid Suspicious Route of Blackhole Nodes in MANET’s:Using A Cooperative Trapping

Mobile Ad hoc Network(MANET)is decentralized wireless network and can communicate without existing infrastructure in many areas.MANET is vulnerable to various attacks that affect its performance such as blackhole attack.Blackhole attacker,inject fault routing information to persuade the source node to select the path with malicious node as the shortest path.To eliminate malicious nodes from launching any collaborative attack.A cooperative Trapping Approach(CTA)was proposed based on modifying Ad-hoc On-demand Distance Vector(AODV)routing protocol and trapping the malicious nodes by responding to the trap request message.The approach aims to eliminate and rule out both single and collaborative malicious blackhole nodes from any attack.The approach realizes a backward tracking mechanism to perform the elimination process.The proposed algorithm(CTA)was executed using NS-2 network simulator.The performance metrics that has been considered to evaluate the performance of the proposed algorithm such as throughput,end to end delay,packet delivery ratio,and consuming energy.The experimental results have shown the performance metrics of the proposed approach outperformed other state of at algorithms.

基于NS2的针对AODV协议BLACKHOLE ATTACK仿真研究

针对未来战场上MANET的大量应用,本文介绍了MANET及AODV协议的BLACKHOLE ATTACK(黑洞攻击)原理,利用NS2仿真工具对黑洞攻击进行建模并仿真,对比分析了在有无黑洞节点两种情况下不同数量移动节点的场景下的攻击效果,得到了分组传输率、端到端的平均时延、归一化的路由开销等统计结果,达到了仿真目的,为部队训练、作战提供指导。

Between Quantum Mechanics and General Relativity

The origin of elementary particle mass is considered as a function of n-valued graviton quanta. To develop this concept we begin in a cold region of “empty space” comprised of only microscopic gravitons oscillating at angular frequency ω. From opposite directions enters a pair of stray protons. Upon colliding, heat and energy are released. Customarily, this phase and what follows afterward would be described by Quantum Chromodynamics (QCD). Instead, we argue for an intermediary step. One in which neighboring gravitons absorb discrete amounts of plane-wave energy. Captured by the graviton, the planewave becomes a standing wave, whereupon its electromagnetic energy densities are converted into gravitational quanta. Immediately thereafter an elementary particle is formed and emitted, having both mass and spin. From absorption to conversion to emission occurs in less than 3.7 × 10−16 s. During this basic unit of hybrid time, general relativity and quantum physics unite into a common set of physical laws. As additional stray protons collide the process continues. Over eons, vast regions of spacetime become populated with low-mass particles. These we recognize to be dark matter by its effects on large scale structures in the universe. Its counterpart, dark energy, arises when the conversion of gravitational quanta to particle emission is interrupted. This causes the gravitational quanta to be ejected. It is recognized by its large scale effects on the universe.

KAM and Geodesic Dynamics of Blackholes

In this paper we apply KAM theory and the Aubry-Mather theory for twist maps to the study of bound geodesic dynamics of a perturbed blackhole background.The general theories apply mainly to two observable phenomena:the photon shell(unstable bound spherical orbits)and the quasi-periodic oscillations(QPO).We prove that there is a gap stTucture in the photon shell that can be used to reveal information of the perturbation.

Fuzzy Reputation Based Trust Mechanism for Mitigating Attacks in MANET

Mobile Ad-hoc Networks(MANET)usage across the globe is increas-ing by the day.Evaluating a node’s trust value has significant advantages since such network applications only run efficiently by involving trustable nodes.The trust values are estimated based on the reputation values of each node in the network by using different mechanisms.However,these mechanisms have various challenging issues which degrade the network performance.Hence,a novel Quality of Service(QoS)Trust Estimation with Black/Gray hole Attack Detection approach is proposed in this research work.Initially,the QoS-based trust estimation is proposed by using a Fuzzy logic scheme.The trust value of each node is estimated by using each node’s reputation values which are deter-mined based on the fuzzy membership function values and utilizing QoS para-meters such as residual energy,bandwidth,node mobility,and reliability.This mechanism prevents only the black hole attack in the network during transmis-sion.But,the gray hole attacks are not identified which in turn increases the pack-et drop rate significantly.Hence,the gray hole attack is also detected based on the Kullback-Leibler(KL)divergence method used for estimating the statistical mea-sures.Additional QoS metrics are considered to prevent the gray hole attack,such as packet loss,packet delivery ratio,and delay for each node.Thus,the proposed mechanism prevents both black hole and gray hole attacks simultaneously.Final-ly,the simulation results show that the effectiveness of the proposed mechanism compared with the other trust-aware routing protocols in MANET.

基于BGP协议的IP黑名单分发系统

在网络中设置IP黑名单,可以极大的减少网络安全事件的发生。系统将IP黑名单信息存放在数据库中,简化的BGP协议客户端读取数据库中的信息,利用BGP协议将IP黑名单更新给路由服务器(Router Server)并分发到各个路由器上。数据库存放的IP黑名单信息易于由程序自动进行添加、删除等操作,BGP协议的应用使得系统的可扩展性很强,路由器的管理员可选择性应用IP黑名单,灵活性更好。

无线移动Ad Hoc网络的安全研究

Ad Hoc网络有其自身优于其他网络的特点,但是这些特点不可避免的导致了它抵抗攻击的脆弱性,故安全性的研究成为Ad Hoc网络发展迫切解决的问题。在Ad Hoc网络中网络威胁和急待解决的问题,从网络的每层即网络应用层、传输层、网络层、数据链路层、物理层来分析关注Ad Hoc网络的安全性问题,给出每层中可能出现的安全威胁,以及对安全问题给出一定的解决方案。

REDUCING BURST PACKET LOSS THROUGH ROUTE-FREE FORWARDING

It is well known that today's inter-domain routing protocol, Border Gateway Protocol (BGP), converges slowly during network failures. Due to the distribution nature of Internet routing decisions and the rate-limiting timer Minimum Route Advertisement Interval (MRAI) of BGP, unavoidable convergence latency is introduced in reaction to network changes. During the period of convergence temporarily routing table inconsistencies cause short-term routing blackholes and loops which result in widespread temporary burst packet loss. In this paper, we present ROute-Free Forwarding (ROFF) - a novel technique for packet delivering continuously during periods of convergence. With slightly modifications on IP packet header and BGP, route loops and blackholes can be avoided. Our preliminary evaluation demonstrates that ROFF succeeds in reducing the number of Autonomous Systems (ASes) which experience burst packet loss and the duration of packet loss.

The astrophysical gravitational wave stochastic background

A stochastic background of gravitational waves with astrophysical origins may have＇resulted from the superposition of a large number of unresolved sources since the beginning of stellar activity. Its detection would put very strong constraints on the physical properties of compact objects, the initial mass function and star for- marion history. On the other hand, it could be a ＇noise＇ that would mask the stochastic background of its cosmological origin. We review the main astrophysical processes which are able to produce a stochastic background and discuss how they may differ from the primordial contribution in terms of statistical properties. Current detection methods are also presented.

State transitions triggered by inverse magnetic field: probably applied in high-mass X-ray binaries?

Previous works suggested that the state transitions in an X-ray binary can be triggered by accret- ing an inverse magnetic field from its companion star. A key point of this mechanism is the accretion and magnification of large-scale magnetic fields from the outer boundary of a thin disk. However, how such a process can be realized is still an open question. In this work, we check this issue in a realistic X-ray binary system. According to our calculations, a quite strong initial magnetic field, B - 10^2 - 10^3 G, is required in order to assure that the large-scale magnetic field can be effectively dragged inward and magnified with the accretion of gas. Thus, such a picture probably can be present in high-mass X-ray binaries possessing a strong stellar magnetic field, e.g., Cyg X-1.

The Principles of Causal Conspiracy

The human mind understands logical processes and causality and formulates theories based on logical descriptions of empirical evidence. The Principles of Causal Conspiracy is based on defining information as logical charges similar to electric charges. Such information charges can be modeled in the vacuum of a quantum probability firmament as symmetry of quantum charges with a zero net charge. Observation of a state lifts one of these charges in a M&oumlbius transformation from a multipolar field of possibilities that maximizes a local monopole field that is observable. In the first of several papers, I introduce new and profound principles, the Principles of Causal Conspiracy, to provide a consistent epistemology for quantum theory, relativity theory and all the known sciences.

Rotating Squeezed Vacua as Time Machines

Squeezed quantum vacua seems to violate the averaged null energy conditions (ANEC’s), because they have a negative energy density. When treated as a perfect fluid, rapidly rotating Casimir plates will create vorticity in the vacuum bounded by them. The geometry resulting from an arbitrarily extended Casimir plates along their axis of rotation is similar to van Stockum spacetime. We observe closed timelike curves (CTC’s) forming in the exterior of the system resulting from frame dragging. The exterior geometry of this system is similar to Kerr geometry, but because of violation of ANEC, the Cauchy horizon lies outside the system unlike Kerr blackholes, giving more emphasis on whether spacetime is multiply connected at the microscopic level.

Security Routing Protocol For The Wireless Mesh Networks (WMNs)

The pretty promising Wireless Mesh Networking technique, which is regarded as the next generation wireless Internet, not only possesses the normal features of wireless networks, but also has the advantages of multi-hop, self-organizing, etc. However, the great strength of the Mesh Networks also lead to a serious problem in the perspective of network security. This paper starts with the security issue of WMN routing and puts forward the corresponding solutions to the two kinds of routings' security, such as adding the public/private (Pi/Si) key to the AODV to solve the problem of black hole and adding the credit value of nodes to the DSR to improve the security.