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Author(s):  
Arudra Annepu ◽  
◽  
Priti Mishra ◽  

Wireless network technically, refers to the category of network in which communication is carried out without using wires. In modern era wireless network has great importance because the communication is taking place with the use of radio waves. Thus, the use of ad-hoc network starts yielding a great importance in variety of applications. The certain research work is carried out in this particular field. MANET is a constructed from various mobility in the form of mobile nodes and anytime without any need of fixed infrastructure. MANET can be made on fly due to lack of fixed infrastructure. MANET is numerous threats types of attacks due to dynamic changing topologies and wireless medium. Security of the MANET becomes one of the challenging tasks. Black hole attacks is the main type of attack that are possible in MANET. Black hole node not forward any data packets to the neighbour node instead it drops all the data packets. Black hole attacks are bit hard to detect due to lack of centralized access. This research work concentrates to enhance the security of MANET by identifying and blocking black hole assaults from occurring. A reactive routing system such as Ad-Hoc on Demand Distance Vector has previously been used to address security problems in the MANET (AODV). Various attack types were investigated, and the consequences of these assaults were detailed by describing how MANET performance was disrupted. Network Simulator 3 (NS3) is used for the simulation process.


Author(s):  
Mohammed Erritali ◽  
Bouabid El Ouahidi

In recent years, the security issues on Vehicular ad hoc networks (VANETs) have become one of the primary concerns. The VANET is inherently very vulnerable to attacks than wired network because it is characterized by high mobility, shared wireless medium and the absence of centralized security services offered by dedicated equipment such as firewalls and authentication servers. Attack countermeasures such as digital signature and encryption, can be used as the first line of defense for reducing the possibilities of attacks. However, these techniques have limited prevention in general, and they are designed for a set of known attacks. They are unlikely to avoid most recent attacks that are designed to circumvent existing security measures. For this reason, there is a need of second technique to “detect and notify” these newer attacks, i.e. “intrusion detection”. This article aims to present and classify current techniques of Intrusion Detection System (IDS) aware VANETs.


2021 ◽  
Author(s):  
◽  
Zakwan Al-Arnaout

<p>Recently, Wireless Mesh Networks (WMNs) have attracted much of interest from both academia and industry, due to their potential to provide an alternative broadband wireless Internet connectivity. However, due to different reasons such as multi-hop forwarding and the dynamic wireless link characteristics, the performance of current WMNs is rather low when clients are soliciting Web contents. Due to the evolution of advanced mobile computing devices; it is anticipated that the demand for bandwidth-onerous popular content (especially multimedia content) in WMNs will dramatically increase in the coming future.  Content replication is a popular approach for outsourcing content on behalf of the origin content provider. This area has been well explored in the context of the wired Internet, but has received comparatively less attention from the research community when it comes to WMNs. There are a number of replica placement algorithms that are specifically designed for the Internet. But they do not consider the special features of wireless networks such as insufficient bandwidth, low server capacity, contention to access the wireless medium, etc.  This thesis studies the technical challenges encountered when transforming the traditional model of multi-hop WMNs from an access network into a content network. We advance the thesis that support from packet relaying mesh routers to act as replica servers for popular content such as media streaming, results in significant performance improvement. Such support from infrastructure mesh routers benefits from knowledge of the underlying network topology (i.e., information about the physical connections between network nodes is available at mesh routers).  The utilization of cross-layer information from lower layers opens the door to developing efficient replication schemes that account for the specific features of WMNs (e.g., contention between the nodes to access the wireless medium and traffic interference). Moreover, this can benefit from the underutilized resources (e.g., storage and bandwidth) at mesh routers. This utilization enables those infrastructure nodes to participate in content distribution and play the role of replica servers.  In this thesis, our main contribution is the design of two lightweight, distributed, and scalable object replication schemes for WMNs. The first scheme follows a hierarchical approach, while the second scheme follows a flat one. The challenge is to replicate content as close as possible to the requesting clients and thus, reduce the access latency per object, while minimizing the number of replicas. The two schemes aim to address the questions of where and how many replicas should be placed in the WMN. In our schemes, we consider the underlying topology joint with link-quality metrics to improve the quality of experience. We show using simulation tests that the schemes significantly enhance the performance of a WMN in terms of reducing the access cost, bandwidth consumption and computation/communication cost.</p>


2021 ◽  
Author(s):  
◽  
Zakwan Al-Arnaout

<p>Recently, Wireless Mesh Networks (WMNs) have attracted much of interest from both academia and industry, due to their potential to provide an alternative broadband wireless Internet connectivity. However, due to different reasons such as multi-hop forwarding and the dynamic wireless link characteristics, the performance of current WMNs is rather low when clients are soliciting Web contents. Due to the evolution of advanced mobile computing devices; it is anticipated that the demand for bandwidth-onerous popular content (especially multimedia content) in WMNs will dramatically increase in the coming future.  Content replication is a popular approach for outsourcing content on behalf of the origin content provider. This area has been well explored in the context of the wired Internet, but has received comparatively less attention from the research community when it comes to WMNs. There are a number of replica placement algorithms that are specifically designed for the Internet. But they do not consider the special features of wireless networks such as insufficient bandwidth, low server capacity, contention to access the wireless medium, etc.  This thesis studies the technical challenges encountered when transforming the traditional model of multi-hop WMNs from an access network into a content network. We advance the thesis that support from packet relaying mesh routers to act as replica servers for popular content such as media streaming, results in significant performance improvement. Such support from infrastructure mesh routers benefits from knowledge of the underlying network topology (i.e., information about the physical connections between network nodes is available at mesh routers).  The utilization of cross-layer information from lower layers opens the door to developing efficient replication schemes that account for the specific features of WMNs (e.g., contention between the nodes to access the wireless medium and traffic interference). Moreover, this can benefit from the underutilized resources (e.g., storage and bandwidth) at mesh routers. This utilization enables those infrastructure nodes to participate in content distribution and play the role of replica servers.  In this thesis, our main contribution is the design of two lightweight, distributed, and scalable object replication schemes for WMNs. The first scheme follows a hierarchical approach, while the second scheme follows a flat one. The challenge is to replicate content as close as possible to the requesting clients and thus, reduce the access latency per object, while minimizing the number of replicas. The two schemes aim to address the questions of where and how many replicas should be placed in the WMN. In our schemes, we consider the underlying topology joint with link-quality metrics to improve the quality of experience. We show using simulation tests that the schemes significantly enhance the performance of a WMN in terms of reducing the access cost, bandwidth consumption and computation/communication cost.</p>


Webology ◽  
2021 ◽  
Vol 18 (Special Issue 04) ◽  
pp. 752-764
Author(s):  
R. Deeptha

Routing is portrayed as one of the most important prevailing challenges in research with reference to multi-hop networks in a wireless environment. Opportunistic routing (OR) protocol is an emerging area related to research, due to the improvement in communication reliability, compared to the traditional routing models. The major perception related to OR is to determine a group of neighboring node candidates, named as a candidate set using the advantages of broadcast capability of the wireless medium thereby to collaboratively transmit data packets towards the destination using the coordination of the forwarded candidate set. The design and performance of OR protocols over multi-hop wireless networks mainly depend on the processes of forwarding selection of candidates and assignment of priorities. Therefore, the researchers have designed and developed several different algorithms for those OR processes. In this paper, following a short outline on traditional routing and OR protocols, metrics involved in the design of existing OR protocols, classification of OR based protocols, and hurdles in the design of OR protocols over multi-hop wireless networks are examined. More precisely, the OR protocols are divided into two categories, based on the forwarding candidate set selection and forwarding candidate coordination methods. Furthermore, the most significant challenges of OR protocol design, such as prioritization of forwarding candidates, utilizing the cross-layer approach for candidate coordination, and achieving the quality of service also investigated.


Author(s):  
Meenigi Ramesh Babu ◽  
K. N. Veena

With the advanced technologies, IoT has widely emerged with data collection, processing, and communication as well in smart applications. The wireless medium in the IoT devices would broadcast the data, which makes them easily targeted by the attacks. In the local network, the normal communication attack is restricted to small local domain or local nodes. However, the attack present in IoT devices gets expanded to a large area that would cause destructive effects. The heterogeneity and distribution of IoT services/applications make the security of IoT a more challenging and complex one. This paper aims to propose a bi-level flow based anomalous activity identification system in IoT. Initially, the flow based features get extracted along with the statistical features like mean, median, variance, correlation, and correntropy. Subsequently, Bi-level classification is carried out in this work. In level 1, the presence of attack is detected and the level 2 classification classifies the type of attack. A decision tree is used for detecting the attacks by checking whether the network traffic is anomalous traffic or normal traffic. In level 2, an Optimized Neural network (NN) is used for categorizing the attacks in IoT with the knowledge of flow features and statistical features. To make the detection and classification more accurate, the weight of NN will be optimally tuned by a new Combined Whale SeaLion Algorithm (CWSA) that hybridizes the concepts of both SLnO and WOA. At last, the performance of the adopted method is computed over other traditional models in terms of accuracy, sensitivity, specificity, precision, FPR, FDR, FNR, NPV, F1-score, and MCC.


Sensors ◽  
2021 ◽  
Vol 21 (16) ◽  
pp. 5520
Author(s):  
Phi Le Nguyen ◽  
Van Quan La ◽  
Anh Duy Nguyen ◽  
Thanh Hung Nguyen ◽  
Kien Nguyen

In wireless rechargeable sensor networks (WRSNs), a mobile charger (MC) moves around to compensate for sensor nodes’ energy via a wireless medium. In such a context, designing a charging strategy that optimally prolongs the network lifetime is challenging. This work aims to solve the challenges by introducing a novel, on-demand charging algorithm for MC that attempts to maximize the network lifetime, where the term “network lifetime” is defined by the interval from when the network starts till the first target is not monitored by any sensor. The algorithm, named Fuzzy Q-charging, optimizes both the time and location in which the MC performs its charging tasks. Fuzzy Q-charging uses Fuzzy logic to determine the optimal charging-energy amounts for sensors. From that, we propose a method to find the optimal charging time at each charging location. Fuzzy Q-charging leverages Q-learning to determine the next charging location for maximizing the network lifetime. To this end, Q-charging prioritizes the sensor nodes following their roles and selects a suitable charging location where MC provides sufficient power for the prioritized sensors. We have extensively evaluated the effectiveness of Fuzzy Q-charging in comparison to the related works. The evaluation results show that Fuzzy Q-charging outperforms the others. First, Fuzzy Q-charging can guarantee an infinite lifetime in the WSRNs, which have a sufficient large sensor number or a commensurate target number. Second, in other cases, Fuzzy Q-charging can extend the time until the first target is not monitored by 6.8 times on average and 33.9 times in the best case, compared to existing algorithms.


Author(s):  
Mr. Vinod Kumar S

This paper focuses on developing an Unmanned Ground Vehicle (UGV) wireless robot. It can sense the different parameters of the surroundings; transmit the data through a wireless medium and display data in LCD as well as on a Remote PC. It controls the direction of the robot from a remote location using wireless communication and thereby performing military surveillance and analysing the battlefield environment and challenges that the soldiers may potentially face. By using a Wi-Fi camera and many sensors the robot can help the soldiers in the war fields to examine various environmental conditions and challenges. The arduino and NRF (Nordic Radio Frequency) technologies are used to achieve the above tasks. The different sensors and the robotic arm are connected to the Arduino Uno which in turn is connected to the Nordic Radio Frequency module. Data transmission and receiving are done through Nordic Radio Frequency communication technology. The proposed model eliminates the limitations of the existing models and thus provides better assistance to the soldiers and enables them to handle their missions better.


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