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Localization is one of the main problems in Mobile Wireless Sensor Networks, since it provides the location of an event occurrence. This paper presents a performance evaluation of the localization algorithms: Multilateration Algorithm, Weighted Multilateration Algorithm and Probabilistic Multilateration Algorithm (PMA). In addition, we propose an Improved Probabilistic Multilateration Algorithm that decreases the localization error of the interest node by using an approach that computes iteratively the position of a node of interest until it reaches the solution that minimizes the localization error. The proposed approach regards the noisy environment by its impact on a correlation matrix that involves the variance of the separation distance between the node of interest and the respective reference nodes (RNs). Furthermore, we also introduce a constant parameter called damping factor; which enhances the convergence of the localization algorithm providing the solution that minimizes the localization error. In this study, we evaluate localization algorithms in a single-hop and multi-hop scenarios considering a distribution with solid geometry of the RNs and randomly distributed RNs in both scenarios. The results we obtained show that our proposed algorithm Improved PMA presents a better performance according to the Normalized Root Mean Squared Error varying the number of reference nodes and noise proportion.

The rapid rate of dependence over internet usage using digital devices also results in enormous data traffic. The conventional way to handle these services is to increase the infrastructure. However, it results in high cost of implementation. Therefore, to overcome the data burden, researchers have come up with data offloading schemes using solutions for NP-hard Target Set Selection (TSS) problem. Our work focuses on TSS optimization and respective data offloading scheme. We propose a heuristics-based optimal TSS algorithm, a distinctive community identification algorithm, and an opportunistic data offloading algorithm. The proposed scheme has an overall polynomial time complexity of the order O(k3), where k is the number of nodes in the primary target set for convergence. However we have obtained its realization to linear order for practical reasons. To validate our results, we have used state-of-the-art datasets and compared it with literature-based approaches. Our analysis shows that the proposed Final Target Set Selection (FTSS) algorithm outperforms the greedy approach by 35% in terms of traffic over cellular towers. It reduces the traffic by 20% as compared to the heuristic approach. It has 23% less average latency in comparison to the community-based algorithm. [ABSTRACT FROM AUTHOR]

Body Area Networks (BODYNETs) or Wireless Body Area Networks (WBAN), being an important type of ad-hoc network, plays a vital role in multimedia, safety, and traffic management applications. In BODYNETs, rapid topology changes occur due to high node mobility, which affects the scalability of the network. Node clustering is one mechanism among many others, which is used to overcome this issue in BODYNETs. There are many clustering algorithms used in this domain to overcome this issue. However, these algorithms generate a large number of Cluster Heads (CHs), which results in scarce resource utilization and degraded performance. In this research, an efficient clustering technique is proposed to handle these problems. The transmission range of BODYNET nodes is dynamically tuned accordingly as per their operational requirements. By optimizing the transmission range, the packet loss ratio is minimized, and link quality is improved, which leads to reduced energy consumption. To select optimal CHs the Whale Optimization Algorithm (WOA) is used based on their fitness, which enhances the network performance by reducing routing overhead. Our proposed scheme outclasses the existing state-of-the-art techniques, e.g., Ant Colony Optimization (ACO), Gray Wolf Optimization (GWO), and Dragonfly Optimization Algorithm (DFA) in terms of energy consumption and cluster building time. [ABSTRACT FROM AUTHOR]

In time driven data-gathering, sensor nodes generate periodic data which are gathered at the base-station. Whereas in event driven data gathering, sensors remain idle until a critical event occurs and then the event information is sent quickly to the central unit. In hybrid data-gathering, the nodes switches between time and event-driven strategy. In this paper, we propose a hybrid data-gathering protocol that minimizes the critical event reporting delay, using anycasting forwarding techniques, and maximizes the network lifetime using sleep/wake scheduling. In our protocol, the sensor nodes generate periodic events and if the nodes detect a critical event, the event information is sent quickly to the central unit. We estimate the expected critical event reporting delay using stochastic approach and validate the same in a Monte-Carlo simulation. We show the effectiveness of our protocol, that minimizes the critical event reporting delay, using ns2 simulation, and compare our protocol with existing hybrid data-gathering protocols. [ABSTRACT FROM AUTHOR]

Background. The task of building a network with a continuous mode of data transmission for mobile nodes is to build a wireless network and maintain a state of loss of the minimum number of packets during the exchange of information. One of the main problems of MANET (Mobile Ad hoc Networks) network management is their dynamics and the fact that mobile devices are limited in their computing capabilities. There is a problem of traffic routing within MANET networks and the internal hierarchy of transmitters involved in the system. These networks also have problems with bandwidth optimization and power management. Lack of fixed topology introduces new scientific problems, such as network configuration, device search and topology support, as well as special addressing and self-destruction of the network. This task is relevant for data transmission between mobile devices in terms of reconnaissance operations. Objective. The goal of the article is the research of reducing packet delays in nodes during dynamic routing, reducing service traffic and software optimization of data transmission in MANET relative to existing methods. Methods. To achieve this goal, we use computer simulation, statistical and empirical methods. Based on the optimization of dynamic routing using the Ad hoc On-Demand Distance Vector algorithm, four main indicators are identified: speed of path establishment, message delay in one node, occurrence of loops, the amount of service traffic. To test the proposed method, a graph of twelve vertices simulating a wireless peer-to-peer MANET network is simulated. Testing is performed in more than a hundred iterations. At each iteration, the vertices of the network graph are randomly selected and the data transfer between each vertex of the graph is modeled. Results. The use of the created software provides the analysis of the indicators of the quality of continuous data transmission and network routing by the proposed method. The proposed method shows reducing the amount of office traffic by 15 % and the best results by 5–10 % reduction of delay time within the node and when processing messages. Conclusions. A method is proposed to reduce the delay time within a node that changes its position when processing a message, to reduce the amount of service traffic when transmitting data between nodes in the MANET network. Computer simulation is used to study the proposed method.

Localization has been a well-investigated problem in the past decade for several networks and is one of the most celebrated applications of adaptive signal processing. However, existing localization algorithms exhibit a significant degradation under non-line of sight (NLOS) conditions, especially in outdoor scenarios. Due to the inherent non-Gaussianity in the NLOS returns, generic mitigation of the degradations due to NLOS remains quite an open challenge. In this regard, information-theoretic learning (ITL) criteria are attractive due to their ability to adapt to arbitrary NLOS distributions and suppress NLOS-induced non-Gaussian processes. In this regard, this letter proposes the use of minimum error entropy with Fiducial points (MEE-FP) in the particular context of round-trip time of arrival (RTTOA) based localization. From the presented simulations, it is observed that the proposed MEE-FP based localization method delivers lower variance under severe NLOS conditions and is closer to the ideal maximum-likelihood solution than contemporary ITL based approaches. Lastly, analytical variance-expressions are derived for the proposed localization technique, which is validated by computer simulations. [ABSTRACT FROM AUTHOR]

The Seas Remain The Base Researched Restrains On This Planet And Various Sea And Seas Applications Seem, By All Accounts, To Be Commonly Moderate In Manhandling The Forefront Data Correspondence Progresses. The Normal And Man-Made Catastrophes That Have Happened Over The Span Of The Latest Couple Of Years Have Made Gigantic Eagerness For Checking Sea Conditions For Logical, Natural, Business, Well-Being, Country Security And Military Needs. Submerged Sensor Systems (Uwsns) Are The Enabling Development For A Broad Assortment Of Utilizations Like Watching The Strong Effects And The Impact Of Environment, Supplement Creation, Oil Recuperation And Transportation. This Paper Presents An Overview Of The Steering Conventions For Uwsn Communication. The Uniqueness Of A Compassionate Attributes Of Flooded Sound Communication Like Low Data Transmission And High Engendering Postpones Compelled To Locate The Effective And Solid Correspondence Convention Over Numerous Jumps Which Can Be Mobile. The Proposed Convention Attempts To Limit This Route Traffic By Recognizing Disappointment In A Progressively Insightful Manner. This Research Paper Examines The Traffic Overhead In Uwsn Situation Utilizing The Conventions Loarp And Mloarp. The Algorithm Plays Out The High Pdr When Utilizing The Mloarp Then Loarp. [ABSTRACT FROM AUTHOR]

The approach of innovation has led the expanded enthusiasm for oneself arranging Ad-hoc Networks. Amongst the various constraints that relates to mobile infrastructure-less networking condition with reduced storage utility as the power storage facilities, influence utilization and vitality advancement stays a very significant issue. In our proposed the self formation nodes in the cloud scenario has been channelized properly through the cluster head (CH) and transmission head (TH) selection. Moreover the proposed technique Friendly Ad-hoc Routing in Cloud Scenario (FARICS) is introduced to enrich the security features of Mobile Ad hoc Network (MANET) architecture. The malicious nodes were found out sincerely through various traffic tables to enrich the security of the MANET. The first preliminary approach of the nodes combination will be vary from cluster to cluster. The CH, TH combination from one cluster to another cluster will be varied according to the sense of the node. The cluster may be a cloud form of organisation to represent the mobile ad hoc nodes. The unique identity of each node were monitored and mapped through the traffic table and the connectivity of the nodes will be strengthening. The simulation will be done with SAODV, SZRP and DMR protocols to get a successful result. [ABSTRACT FROM AUTHOR]

We consider a scenario of broadcasting information over a network of nodes connected by noiseless communication links. A source node in the network has some data packets to broadcast. It encodes these data packets into $n$ coded packets in such a way that any node in the network that receives any $k$ out of the $n$ coded packets will be able to retrieve all the original data packets. The source transmits the $n$ coded packets to its one-hop neighbours. Every other node in the network follows a probabilistic forwarding protocol, in which it forwards a previously unreceived packet to all its neighbours with a certain probability $p$. We say that the information from the source undergoes a “near-broadcast” if the expected fraction of nodes that receive at least $k$ of the $n$ coded packets is close to 1. The forwarding probability $p$ is chosen so as to minimize the expected total number of transmissions needed for a near-broadcast. We study how, for a given $k$ , this minimum forwarding probability and the associated expected total number of packet transmissions varies with $n$. We specifically analyze the probabilistic forwarding of coded packets on two network topologies: binary trees and square grids. For trees, our analysis shows that for fixed $k$ , the expected total number of transmissions increases with $n$. On the other hand, on grids, a judicious choice of $n$ significantly reduces the expected total number of transmissions needed for a near-broadcast. Behaviour similar to that of the grid is also observed in other well-connected network topologies such as random geometric graphs and random regular graphs. [ABSTRACT FROM AUTHOR]

A planar multifunctional four-port antenna system integrated on one substrate applied in the suburban mobile tablet is presented in this paper. The types of these antennas are selected based on different functions and the interactions between them are analyzed and reduced. Two identical T-shaped printed monopole antennas are designed for the MIMO mobile ad-hoc networks (MANET) application. The mutual coupling between the ports of these two MANET antennas is decreased by introducing a decoupling metal strip loaded with an inductor. Two horizontal printed dipoles with parasitic strips are developed to operate in the satellite navigation and communication frequency bands. Through the analysis of the interaction between the MANET antenna and satellite antennas, the satellite antennas with improved broadside radiation patterns are obtained. The performance stability of the proposed antenna system is verified by the investigation of the performances in different gestures. A prototype of the antenna system is fabricated and the measured results show that the proposed antenna system can cover the frequency bands of MANET communication, satellite navigation, and satellite communication with good performances. This proposed multifunctional antenna system is a good choice for the sub-urban mobile terminal systems.

Autonomous vehicles are becoming a reality in places with advanced infrastructure to support their operations. In crowded places, harsh environments, missions that require these vehicles to be aware of the context in which they are operating, and situations requiring continuous coordination with humans such as in disaster relief, advanced-vehicle systems (AVSs) need to be better contextually aware. The vast literature referring to “context-aware systems” is still sparse, focusing on very limited forms of contextual awareness. It requires a structured approach to bring it together to truly realize contextual awareness in AVSs. This paper uses a human-AVSs (HAVSs) lens to polarize the literature in a coherent form suitable for designing distributed HAVSs. We group the relevant literature into two categories: contextual-awareness related to the vehicle infrastructure itself that enables AVSs to operate, and contextual-awareness related to HAVSs. The former category focuses on the communication backbone for AVSs including ad-hoc networks, services, wireless communication, radio systems, and the cyber security and privacy challenges that arise in these contexts. The latter category covers recommender systems, which are used to coordinate the actions that sit at the interface of the human and AVSs, human-machine interaction issues, and the activity recognition systems as the enabling technology for recommender systems to operate autonomously. The structured analysis of the literature has identified a number of open research questions and opportunities for further research in this area.

This paper focuses on developing a new practical classification for ad-hoc networks, where all the past classifications revolve upon three main categories respectively, mobile ad- hoc network (MANET), Vehicle ad-hoc network (VANET) and Flying ad-hoc network (FANET). My new classification will illustrate Underwater vehicle ad-hoc network (UWVANET) as the fourth category in ad-hoc main classification, showing the powerful and the weakness of each category defined. [ABSTRACT FROM AUTHOR]

In periodic data-gathering, sensors can switch on the transceiver only during packet transmission to save energy. Exact clock-synchronization is challenging to achieve because of error present in synchronization protocols. Clock-disagreement increases with time in the absence of synchronization. This paper proposes an Energy-efficient Multi Beacon Guard method (EMBG) to decrease the energy consumption by minimizing the awake time of sender and receiver by periodically switching on and off the receivers during the guard-time. We determine the optimal number-of-times the receiver needs to wake up along with the wake-up intervals to collectively minimize the total energy consumption of the sender–receiver pair during transmission. This paper shows the effectiveness of EMBG in energy conservation and compares with existing approaches using ns2 simulation. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of InformaticsTechnologies is the property of Institute of Informatics, Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Vehicular ad-hoc networks allow vehicles to exchange messages pertaining to safety and road efficiency. Building trust between nodes can, therefore, protect vehicular ad-hoc networks from malicious nodes and eliminate fake messages. Although there are several trust models already exist, many schemes suffer from varied limitations. For example, many schemes rely on information provided by other peers or central authorities, for example, roadside units and reputation management centers to ensure message reliability and build nodes' reputation. Also, none of the proposed schemes operate in different environments, for example, urban and rural. To overcome these limitations, we propose a novel trust management scheme for self-organized vehicular ad-hoc networks. The scheme is based on a crediting technique and does not rely on other peers or central authorities which distinguishes it as an economical solution. Moreover, it is hybrid, in the sense it is data-based and entity-based which makes it capable of revoking malicious nodes and discarding fake messages. Furthermore, it operates in a dual-mode (urban and rural). The simulation has been performed utilizing Veins, an open-source framework along with OMNeT++, a network simulator, and SUMO, a traffic simulator. The scheme has been tested with two trust models (urban and rural). The simulation results prove the performance and security efficacy of the proposed scheme. [ABSTRACT FROM AUTHOR]

Many optimization techniques for networking protocols take advantage of topological information to improve performance. Often, the topological information at the core of these techniques is a centrality metric such as the Betweenness Centrality (BC) index. BC is, in fact, a centrality metric with many well-known successful applications documented in the literature, from resource allocation to routing. To compute BC, however, each node must run a centralized algorithm and needs to have the global topological knowledge; such requirements limit the feasibility of optimization procedures based on BC. To overcome restrictions of this kind, we present a novel distributed algorithm that requires only local information to compute an alternative similar metric, called Load Centrality (LC). We present the new algorithm together with a proof of its convergence and the analysis of its time complexity. The proposed algorithm is general enough to be integrated with any distance vector (DV) routing protocol. In support of this claim, we provide an implementation on top of Babel, a real-world DV protocol. We use this implementation in an emulation framework to show how LC can be exploited to reduce Babel's convergence time upon node failure, without increasing control overhead. As a key step towards the adoption of centrality-based optimization for routing, we study how the algorithm can be incrementally introduced in a network running a DV routing protocol. We show that even when only a small fraction of nodes participate in the protocol, the algorithm accurately ranks nodes according to their centrality. [ABSTRACT FROM AUTHOR]

Copyright of KPI Science News is the property of National Technical University of Ukraine KPI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper details a hardware implementation of a distributed Θ(1) time algorithm allows to select dynamically the master device in ad-hoc or cluster-based networks in a constant time regardless the number of devices in the same cluster. The algorithm allows each device to automatically detect its own status; master or slave; based on identifier without adding extra overheads or exchanging packets that slow down the network. We propose a baseband design that implements algorithm functions and we detail the hardware implementation using Matlab/Simulink and Ettus B210 USRP. Tests held in laboratory prove that algorithm works as expected. [ABSTRACT FROM AUTHOR]

Recently, the deployment and usage of unmanned aerial vehicles (UAVs) to monitor and track a geographical region have been increased exponentially. The network infrastructure designed to deploy UAVs consists of sensors, actuators, and other communication smart devices for data collection and processing. As security and privacy is one of the challenging tasks in such an environment, so to design an efficient and secure data dissemination scheme is a challenging task due to limited storage and computation power of UAVs. To mitigate various attacks in such an environment, several efficient signature schemes were proposed in the literature. However, none of these schemes work well due to high computation and communication costs. To overcome these challenges, this paper presents a short proxy signature (CB-PS) scheme in certificate-based setting. Due to implicit usage of certificates, CB-PS solves inherent key escrow of ID-based designated verifier proxy signature. It also eliminates the necessity of secret key distribution in ID-based schemes. The proposed CB-PS scheme is adaptively unforgeable in a random oracle model. It is also efficient with respect to both signature length and computational complexity. The comparison of computational costs reveals that the proposed scheme consumes the least cost 15.45 ms in comparison to the costs of existing competitive schemes. [ABSTRACT FROM AUTHOR]

We investigate the connectivity of fading wireless ad-hoc networks with a pair of novel connectivity metrics. Our first metric looks at the problem of connectivity relying on the outage capacity of MIMO channels. Our second metric relies on a probabilistic treatment of the symbol error rates for such channels. We relate both capacity and symbol error rates to the characteristics of the underlying communication system such as antenna configuration,modulation, coding, and signal strength measured in terms of Signal-to-Interference-Noise-Ratio (SINR). For each metric of connectivity, we also provide a simplified treatment in the case of ergodic fading channels. In each case, we assume a pair of nodes are connected if their bi-directional measure of connectivity is better than a given threshold. Our analysis relies on the central limit theorem to approximate the distribution of the combined undesired signal affecting each link of an ad-hoc network as Gaussian. Supported by our simulation results, our analysis shows that (1) a measure of connectivity purely based on signal strength is not capable of accurately capturing the connectivity phenomenon, and (2) employing multiple antenna mobile nodes improves the connectivity of fading ad-hoc networks.

Wireless network technology is being applied to a wide range of scientific and engineering problems and across a wide dynamic range of spatial scales. When node placement is constrained by the application (e.g, coupled to sensor placement needs), and can not rely on pre-existing infrastructure (e.g., cellular infrastructure or power-lines), such systems may experience erratic link qualities and intermittent node disconnection. These characteristics, combined with unpredictable environmental conditions, make it difficult to rely upon traditional end to end connections for regular high bandwidth data acquisition and for system management and configuration. We have implemented and deployed such a "challenged network" system of 50 nodes for use by seismologists along a part of the Mesoamerican Subduction Experiment (MASE) broadband seismic array, stretching 500 KM from Acapulco to Tampico through Mexico city. In addition to supporting Delay Tolerant data transfer of relatively high bandwidth seismic data, our system includes a reliable asynchronous remote shell interface (referred to as Disruption Tolerant Shell, DTS) to accomplish the management on these types of system. We present the implementation of this solution and its evaluation on a 13 node portion of the MASE network.

This paper proposes a spectRum Aware cRoss-layEr (RARE) medium access control protocol for cognitive radio ad-hoc networks. The RARE protocol initially splits the network into clusters, where cluster formation is defined as maximum edge biclique problem. Besides, in order to maintain the integrity of the cluster-based network, super-frame structure, and topology maintenance protocols are also presented in this paper. Moreover, RARE also integrates a delay-aware routing protocol, where the routing protocol is defined as a weighted graph problem. It is anticipated that clusters in RARE adapt themselves dynamically with respect to spectrum availability and nodes mobility. Furthermore, the routing protocol in RARE is expected to select stable paths while ensuring faster data delivery from a source node to the destination. Simulation is conducted to evaluate the performance of the proposed RARE protocol, where it is found that RARE outperforms existing approaches by maintaining a lesser number of clusters and a steady number of common channels. The simulation results also show that route selection in RARE proves to be more stable with the lowest packet transmission delay compared with the other approaches.

The research explored the current scenario of crime in Botswana, and the current measures employed to help combat it, including usage of crime prevention clusters. Through usage of the quantitative approach, with the aid of questionnaire and interviews, the research found that, there is an increasingly growth of crime rate in Botswana, sustaining the literature findings. The research highlighted the presence of crime prevention clusters, but noted a disconnection between them and the police. The bleak state of communication between the two, and ineffectiveness of current measures, causes the disconnection. Cluster members have to use own limited resources to report crime to the police, and this disadvantages the crime prevention efforts. Ad-hoc networks with emphasizes on Wi-Fi networks were found to be a solution to the communication gap identified. In conclusion, the authors developed a Wi-Fi network facility model to enable cluster members to make voice calls with no costs.

A new architecture for a mobile ad-hoc communication network is developed, and simulation results show that the proposed MAC protocol can enhance transmission success probability from 0 to 97%. Two novel applications of vehicle-to-vehicle networks are then developed and simulated. The first application is a \Cooperative Adaptive Cruise Con- trol" which uses communicated information to improve on ordinary cruise control systems. Communicating a \virtual brake light" between vehicles is shown to decrease the accelerations required to maintain safe following distances in cut-in and hard braking situations. The second application is a \Cooperative Estimation" algorithm. The idea behind this algorithm is that each vehicle on the road is potentially a driving condition \sensor." By combining data communicated from many vehicles on the roadway, the cooperative estimation algorithm is able to produce estimates of driving time and road condition that are significantly better than those that any one vehicle could produce on its own. While developing the cooperative road condition estimation algorithm, it is found that the problem's crux is at the vehicle level, so the friction estimation problem is then investigated at a vehicle/tire level through exten- sive experimentation. An exciting new type of \slip-based" road condition estimator is developed and experimentally shown to be able to distinguish between wet and dry roads using no dedicated road condition sensors sen- sors. In-depth literature review complements our own results and shows that \slip-based" estimators of the type developed may be very useful to help solve the AHS road condition estimation problem.

In this paper, we consider the simultaneous connectivity of primary and secondary networks forming a cognitive model. It is assumed that the cognitive model includes guard zones that prevent the nodes of the secondary network from being active in the vicinity of primary nodes to limit interference. Under these assumptions, we characterize the region of densities, the transmission radii of the nodes in each of the networks, and the guard zones for which the two networks have a unique unbounded connected component. We prove that this model is feasible, that is, there exists simultaneous connectivity with the unique unbounded connected component in each of the networks. We also provide necessary and sufficient conditions for the simultaneous connectivity of this cognitive model. [ABSTRACT FROM AUTHOR]

In wireless sensor networks applications like rare-event detection, maximizing lifetime, minimizing end-to-end delay, and minimizing the network cost, are some of the most important quality of service requirements. In applications like disastrous or fire event detection, if an event is detected very close to the center facility, the event information should reach to the base-station much faster than an event detected far away. In this work, we are interested to find a minimum cost network for such applications. A stochastic approach is used to find the minimum cost network for given lifetime requirement and spatial differentiated delay constraints. We use Monte-Carlo simulations for validating our analysis. In order to show the effectiveness of our approach, we use network simulator-2 simulations. [ABSTRACT FROM AUTHOR]

Next generation networks are expected to be ultra-dense and aim to explore spectrum sharing paradigm that allows users to communicate in licensed, shared as well as unlicensed spectrum. Such ultra-dense networks will incur significant signaling load at base stations leading to a negative effect on spectrum and energy efficiency. To minimize signaling overhead, an ad-hoc approach is being considered for users communicating in the unlicensed and shared spectrums. For such users, decisions need to be completely decentralized as: 1) No communication between users and signaling from the base station is possible which necessitates independent channel selection at each user. A collision occurs when multiple users transmit simultaneously on the same channel, 2) Channel qualities may be heterogeneous, i.e., they are not same across all users, and moreover, are unknown, and 3) The network could be dynamic where users can enter or leave anytime. We develop a multi-armed bandit based distributed algorithm for static networks and extend it for the dynamic networks. The algorithms aim to achieve stable orthogonal allocation (SOC) in finite time and meet the above three constraints with two novel characteristics: 1) Low complexity narrowband radio compared to wideband radio in existing works, and 2) Epoch-less approach for dynamic networks. We establish convergence of our algorithms to SOC and validate via extensive simulation experiments. [ABSTRACT FROM AUTHOR]

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We present an average case analysis of the minimum spanning tree heuristic for the power assignment problem. The worst‐case approximation ratio of this heuristic is 2. We show that in Euclidean d‐dimensional space, when the vertex set consists of a set of i.i.d. uniform random independent, identically distributed random variables in [0,1]d, and the distance power gradient equals the dimension d, the minimum spanning tree‐based power assignment converges completely to a constant depending only on d. [ABSTRACT FROM AUTHOR]

A mobile ad hoc network (MANET) consists of mobile nodes communicating over wireless channels. Routing in MANETs is very challenging due to the random mobility of nodes and unreliability of wireless channels. Therefore most of the existing routing algorithms make only the best effort to find routes for communication but do not provide any performance guarantee. Because of the widespread use of MANETs in real-time applications, it becomes pertinent to provide deterministic network behavior. Quality of Service (QoS) aims to shape the network behavior and provide performance guarantees. In this work, a novel heuristic called Advanced-Optimised Link State Routing (A-OLSR) protocol is designed to provide QoS. It functions by enhancing the connectivity of nodes and establishing more stable routes as compared to standard best-effort Optimised Link State Routing (OLSR) protocol. The simulation results show that A-OLSR provides lower delay, reduces energy consumption and achieves higher throughput without introducing any additional routing overhead as compared to the standard OLSR and it's variants-A′-OLSR and A′′-OLSR. The results also show that A-OLSR provides scalability since it's performance remains consistent with the increasing size of network. [ABSTRACT FROM AUTHOR]

A prudent attacker tries to maximize profits during an attack, taking into account the investment cost for carrying out the attack; a cost which always exists. This includes the effort of information gathering, the energy and work needed to develop the attack, the risk of being exposed etc. The wormhole attack, in which a non-existent path is augmented to the network coaxing naive nodes to route traffic through the attackers, is accepted as one of the most destructive attacks in ad-hoc networks (e.g. manet s, i o t , wsn , uav s etc.). This research proposes a method to maximize the profit of the attack and challenges the axiomatic assumption of the wormhole attack protocol. We show that up to a specific point, there is a simpler alternative to the attack that does not require the creation of an additional fictitious link; yet, achieves optimal attack coverage. Simulating multiple network node/edge combinations in ns3 , demonstrates how the benefit of every additional dedicated wormhole link is actually small and diminishes as link density increases. Our alternative, based on centrality measures, decreases the chance of being detected by ids/ips as no active topology manipulation is taking place. [ABSTRACT FROM AUTHOR]

The Intelligent Transportation System (ITS) provides wireless and mobile communication between vehicles and infrastructure to improve the safety of transportation and make the journey more enjoyable. This system consists of many fixed and mobile nodes (Vehicles, Trains, Vessels, Air planes), Wireless and Wired Telecommunication Technologies to exchange information between mobile nodes or between mobile nodes and fixed stations. The most common transportation tools are cars. Vehicular Ad-hoc Networks as an Application of Mobile Ad-hoc Networks and one of the subsets of Intelligent Transportation System provides wireless Ad-hoc communication between vehicles. VANET is a mobile wireless technology which is designed to improve safety of transportation with exchanging real time data between vehicles and providing different services to the users. It has special characteristics like high mobility and provides a broad range of services to the users, so it has been emerged as one of the research interests in the field of computer and telecommunication networks. In This paper we present different aspects of ITS and VANET to help the researchers to understand the Architecture, Communication Technologies and Applications of these networks.

Technological advancements in Unmanned Aerial Vehicles (UAV) encourage the use of multi-UAV systems in military and civil applications. The most important benefit of the multi-UAV system is to fulfill missions that require collaborative and cooperative behavior which depends on communication between UAVs. Flying Ad-Hoc Network (FANET) is a technique that both solves the coverage range problem between ground station and the UAVs; and supports real time data transfer without any infrastructure. FANET, which can be considered another type of ad-hoc network, holds all security issues of ad-hoc networks. Besides, it might also have new security problems, because it consists of UAVs. In this paper, FANET security limitations and challenges are surveyed. In addition, open research areas are also discussed.