A neighbor's trust based model for prevention of black hole attack in wireless modile ad hoc networks

Implementing Ad hoc networks are becoming very prevalent during recent years. Security is the most important issue for developing mobile ad hoc networks (MANETs). They expose to various kinds of attacks because of their unique nature in which every node can easily join to network or leave it. Black hole attack is the most probable attack in MANET. In this research we proposed a model for prevention of this attack. It judges on route replies coming from the intermediate node based on a trusted third party which is the destination node. If the source node received an acknowledgement on the route replies sending by an intermediate node, from destination during a specific time, it decides that the path is safe and intermediate node is not malicious. Meanwhile a counter will be set for counting the number of times that each intermediate node introduced a wrong route reply. Every node that proposes a wrong route reply will be recorded in a black list. The process also will be checked for all one hop neighbors of the suspicious node and the history of these nodes will be gathered in the black list, if they proposed a wrong route reply during the route discovery process. When the counter for each node exceed from a specific value, the suspicious nodes will be introduced as black holes and an alarm will be notified to all nodes in the network to remove these malicious nodes from their routing tables. Experimental results show that this model proposes a high rate of packet delivery ratio, with 88% improving network throughput compared with a network exposing in attack situation and decreasing the rate of end to end delay with 38% less than attack situation

A secure blind discrete wavelet transform based watermarking scheme using two-level singular value decomposition

In this paper, a secure blind image watermarking scheme is proposed to improve efficiency of hybrid Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD) based schemes. The main contribution of this research is using two-level singular value decomposition in hybrid DWT + SVD watermarking schemes results to high improvement in both imperceptibility and robustness. Also, security is ensured in this scheme by proposing a two-level authentication system for watermark extraction in which not only the false positive problem is eliminated, when the attacks are very severe, the false negative effect is also detected and prevented. In the proposed scheme, the cover image is initially transformed to DWT and the high frequency sub bands are selected. Subsequently, High (HH) sub band is divided into 8 × 8 non overlapping blocks and the SVD transform is applied to each of them. In SVD transform, the highest energy compaction is in the first row and the first column of the matrix of singular values. These singular values for each block will be collected in a separate matrix and then the second SVD transform will be exerted on the produced matrix. The singular values of the watermark image after exerting one level DWT, is embedded into the singular values of this matrix. Experimental result shows when the scheme is subjected to ten most common types of signal processing and geometric attacks, using the second level of SVD makes it highly robust and imperceptible while it is independent from type of image. So, the proposed scheme is tested and certified for both medical and normal images. This scheme is compared to a range of hybrid schemes using DWT and one level SVD, and experimental results show high improvements in imperceptibility with the average of 46.6950 db and robustness more than 99% and proven efficiency in security

Analysis and evaluation of template based methods against geometric attacks: A survey

Template based methods have been identified as one of the acknowledged methods in image watermarking consisting the influential techniques to prevent geometric attacks. These are added features in the watermarked image by the aim of synchronization recognition without including sensitive information. However, up to now, there is no activity to narrow down each of these methods. This paper, categorized the solutions for prevention and detection of geometric attacks based on predefined templates considered in digital images. Due to this classification in the proposed solutions, a state of the art investigation is performed to evaluate and compare the improvements in this area during 2003 to 2020. The goal is to find the critical factors to make an optimum balance between robustness, imperceptibility, capacity, and to increase security of the watermarking techniques planned in template based methods in order to assist the future researchers to achieve an optimum watermarking algorithm for protection of images against Geometric attacks. The experimental results prove the efficacy of utilizing Pyramidal Just Noticeable Difference (PJND) with high accuracy to increase robustness against more attacks in comparison to the other methods while employing curvelet to hide templates is appropriate to make the capacity of method independent from robustness and imperceptibility

An access control framework in an ad hoc network infrastructure

The union of an arbitrary topology constitutes of self-configuring mobile routers and associated hosts connecting by wireless links is called a mobile ad hoc network (MANET). In this paper, we propose an access control framework for an ad hoc network infrastructure. Compared with the wired and semi wireless network infrastructures in which users should be authenticated and given specific rules for access to the network resources, in an ad hoc network infrastructure some trusted nodes will be required to play the roles of authentication servers and policy enforcement rule servers when the previous servers leave the network. In order to reach to this purpose firstly, a model for Dynamic Monitoring in Ad hoc Networks is described which is going to be used as the trust based part of our proposed model, after that an access control Framework for semi-infrastructure ad hoc networks will be explained. Then, we will introduce our proposed framework to develop the mentioned semi ad hoc framework in a fully ad hoc network environment

Performance analysis in reactive routing protocols in wireless mobile ad hoc networks using DSR, AODV and AOMDV

selecting an appropriate routing protocol for steering data packets is a very important issue to evaluate the performance of wireless mobile ad hoc networks (MANETs). This selection can be difficult in different situations since in such networks there is no specific infrastructure and standard specifications for network development. In this paper we introduce several reactive routing protocols in the MANET and check some performance metrics such as throughput, end to end delay and packet delivery ratio in order to find the best routing protocol based on the enforced conditions in our network. It is observed that in a network with increased number of nodes to maximum 20 nodes, packet delivery ratio and throughput in DSR and AOMDV routing protocols are better than AODV while in checking end to end delay, AOMDV shows less delay than DSR and AODV

Host Feasibility Investigation to Improve Robustness in Hybrid DWT+SVD Based Image Watermarking Schemes

Today, we face different approaches to enhance the robustness of image watermarking schemes. Some of them can be implemented, but others in spite of spending money, energy, and time for programming purpose would fail because of not having a strong feasibility study plan before implementation. In this paper, we try to show a rational feasibility study before implementation of an image watermarking scheme. We develop our feasibility study by proposing three types of theoretical, mathematical, and experimental deductions. Based on the theoretical deduction, it is concluded that the “S” coefficients in the second level of Singular Value Decomposition (SVD) offer high robustness to embed watermarks. To prove this, a mathematical deduction composed of two parts is presented and the same results were achieved. Finally, for experimental deduction, 60 different host images in both normal and medical images from various sizes of 256⁎256 to 1024⁎1024 were imposed to 9 common geometric and signal processing attacks and the resistances of “S” coefficients against the attacks in the first and second levels of SVD were compared. Experimental result shows significant enhancement in stability and robustness of the “S” coefficients in the second level of SVD in comparison to the first level. Consequently all theoretical, mathematical, and experimental deductions confirmed domination of the “S” coefficients in the second level of SVD than the first level. In this paper, we do not show any specific implementation for the watermarking scheme. Instead, we investigate the potential performance gains from the singular values (S), of the second level of SVD and Discrete Wavelet Transform (DWT), and prove their superiority in comparison to conventional SVD+DWT watermarking schemes

A survey for prevention of black hole attacks in wireless mobile adhoc networks using IDS agents

Mobile ad hoc network is a set of autonomous nodes communicate with each other while they are free from predefined infrastructure. Due to this specification deploying of such networks is very easy and today it is getting more ubiquitous. In this paper, we reviewed different IDS based solutions against Blackhole attacks in Mobile Ad-Hoc networks and thoroughly analyzed these schemes to find out their advantages and disadvantages

A secure model for prevention of black hole attack in wireless mobile ad hoc networks

Implementing Ad hoc networks are becoming very prevalent during recent years. Security is the most important issue for developing mobile ad hoc networks (MANETs). They expose to various kinds of attacks because of their unique nature in which every node can easily join to network or leave it. Black hole attack is the most probable attack in MANET. In this research we proposed a model for prevention of this attack. It judges on route replies coming from the intermediate node based on a trusted third party which is the destination node. If the source node received an acknowledgement on the route replies sending by an intermediate node, from destination during a specific time, it decides that the path is safe and intermediate node is not malicious. Meanwhile a counter will be set for counting the number of times that each intermediate node introduced a wrong route reply. Every node that proposes a wrong route reply will be recorded in a black list. The process also will be checked for all one hop neighbors of the suspicious node and the history of these nodes will be gathered in the black list, if they proposed a wrong route reply during the route discovery process. When the counter for each node exceed from a specific value, the chain of suspicious nodes will be introduced as black holes and an alarm will be notified to all nodes in the network to remove these malicious nodes from their routing tables

A survey for prevention of black hole attacks in wireless mobile adhoc networks using trusted neighbor nodes

Wireless mobile ad hoc networks can be regarded as a novel paradigm in wireless communication whereas wireless nodes act as either computers or routers. The transmission of information is performed via wireless links in which the radio frequencies are relayed to the outside of their radio range by their neighbor nodes, so in a MANET neighbor nodes play an important role in the transmission of information. This paper, categorized the solutions for prevention of black hole attacks based on the behavior of their neighbor nodes to find the attacker. Due to this classification in the proposed solutions we do not use any computation based on cryptographic or IDS based methods, instead we judge on malicious behavior just by getting the confirmation of the neighbor nodes to use the simplicity of these methods and avoid computational overheads