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The Ad hoc network is a part of the IoT environment, including several types of networks like MANET. It uses different categories of routing protocol, but the OLSR routing protocol is the best one for MANET. The mobility concept has an impact on the evolution of network performances. In the OLSR routing protocol, this mobility influences on the choice of the MultiPoint Relay (MPR). In this paper, the main objective is to develop an algorithm enhancing MPR selection process in such networks. This algorithm based on Average Spatial Dependency metric “ASD” linked to the average Relative Speed “RS” and the average Relative Acceleration “RA”. Each node shares these values with its neighbors using the messages of OLSR routing protocol (Hello and TC messages). Furthermore, if the nodes have equal reachability, the highest ASD value will be selected as a criterion of the choice of their MPR set. In the simulation, we have applicated the Manhattan mobility model in the MANET network, and we have used the NS3 simulator. The results of this simulation have shown that the mobility concept could change network performances in terms of packet loss, end-to-end delay, and Throughput.

With the advances of mobile technologies, users must enjoy digital environment using smart mobile interfaces without any kind of restrictions. In addition, different users want to easily communicate and use media contents through the network platform. Recently, Mobile Ad hoc Networks (MANETs) where Optimized Link State Routing (OLSR) used as routing protocol, can be used to ensure communications in digital environment. In such networks, each node broadcasts the Topology Control (TC) messages to forward the network topology with other devices using a mechanism called MultiPoint Relays (MPR). However, the control traffic broadcasting method can influence different performances, and duplicate TC messages transmission will always exist. In this paper, we propose a minimization-based approach considering both the network overhead and energy consumption. The main goal of this solution is to provide users with smart mobile networking in order to optimize communications between different devices. Moreover, the proposal which is based on the linear programming approach, permits to control the duplicate TC transmission to prolong the network lifetime by saving the energy consumption in order to offer a smart digital environment.

In our everyday life, we are very interested in wireless connection technologies. In addition, the use of mobile devices and applications which are based on wireless networking is continuously increasing day after day. As the future Internet architecture, security concept can offer superior architectural support for Mobile Ad Hoc Networks (MANETs). Therefore, this concept, which is an important cross-cutting research field, is gradually forming. The key novelty of this paper, is to provide the references and guidelines to well guide the readers approaching studies on the new research fields about this concept. First of all, we introduce the background of MANETs and analyze its development trends, and then interpret security requirements and sketch an overview about challenges and attacks in such networks. Subsequently, we define, for the first time a new research field entitled Cooperative Internet of MANETs (CIMANET) which will be introduced as the new cross-cutting area. In addition, we provide a description of many existing security algorithms with a comparative analysis of these various mechanisms.

International audience; Behavior of the propagation medium in reaction with electromagnetic fields is described by its dielectric permittivity; this electric property is a function of the physical characteristics of the medium and those of the propagating wave. Among the parameters, which considerably affect the dielectric permittivity of a medium, its water content. In fact, when the snow wetness varies from 0 to 50% in the melting layer, real part of the mixture permittivity varies from 1.47 to 5.86. Similarly, when soil moisture varies from 0 to 40% real and imaginary parts of effective permittivity of soil, air and water mixture vary from 4.13 to 24.85 and from 0 to 3.44 respectively. This dynamism in the permittivity as a function of the humidity is able to alter the efficiency of the antenna within the application. In this paper, we propose a study to analyze the impact of wetness on the performance of a dipole antenna with central frequency of 900 MHz. The study was carried out by simulating the behavior of the dipole antenna model in Finite Element Method (FEM) full wave simulator with different values of the water content of two propagation mediums: melting layer and soil. Simulation results concerning the resonant frequency, bandwidth, directivity are presented through paragraphs of the paper.

In Mobile Ad hoc Networks (MANETs), with Optimized Link State Routing Protocol (OLSR) the mobility concept is an essential element which can result in the evolution of network performances. In this paper, the main objective is to develop an algorithm to improve the MultiPoint Relay (MPR) selection process in such networks. This algorithm is based on the Mobility Rate (MR) which in turn is relied on the relative velocity of nodes. Additionally, in this algorithm, each node keeps a mobility rate record of other nodes. Moreover, this mobility value will be exchanged between nodes using OLSR messages (HELLO and Topology control (TC)). Furthermore, this value will be used as a criterion when a node chooses their MPR set. In addition, the simulation results using Network Simulator 3 (NS3) have shown that the mobility concept could improve network performances in terms of the throughput, packet received, packet loss, packet delivery ratio and packet forwarded. Moreover, and through this paper the proposed algorithm can be used as a functional mobility mechanism to improve network performances in MANETs.

Game theory may offer a useful mechanism to address many problems in mobile ad hoc networks (MANETs). One of the key concepts in the research field of such networks with Optimized Link State Routing Protocol (OLSR) is the security problem. Relying on applying game theory to study this problem, we consider two strategies during this suggested model: cooperate and not-cooperate. However, in such networks, it is not easy to identify different actions of players. In this paper, we have essentially been inspired from recent advances provided in game theory to propose a new model for security in MANETs. Our proposal presents a powerful tool with a large number of players where interactions are played multiple times. Moreover, each node keeps a cooperation rate (CR) record of other nodes to cope with the behaviors and mitigate aggregate effect of other malicious devices. Additionally, our suggested security mechanism does not only take into consideration security requirements, but also take into account system resources and network performances. The simulation results using Network Simulator 3 are presented to illustrate the effectiveness of the proposal.

Mobile ad hoc networks (MANETs) is a multihop wireless communication network supporting mobile users (nodes) without any existing infrastructure and depend of the individual behavior of the nodes. This nature of MANETs imposes the cooperation among nodes to improve quality of service and security especially that mobility and energy are the most important criteria in MANETs. In such networks, devices can have different configurations, and should cooperate to ensure the existence of such networks. Cooperation enforcement mechanism do not provide strong authentication of entities. However, cooperation may be more difficult to apply in MANETS than infrastructure based networks due to many reasons already mentioned. In this paper we'll present a correct strategy based on cooperation rate (CR) to enforce cooperation and communication between nodes in MANET using OLSR routing protocol. The concept of this strategy based on game theory is focused on track keeps by each nodes and calculate the CR of other nodes. The CR is calculated based on various types of OLSR messages (HELLO, TC, MID and HNA) sent among nodes, and also based on different network processing (forwarding and routing).

In this paper, we'll try to discuss the cooperation of nodes representing one of the important factors in improving the quality of service (QoS) and security in mobile ad hoc networks (MANETs). The routing protocols for MANETs are designed based on the assumption that all participating nodes are fully cooperative. In such networks, the Selfish behaviour is among the big challenges and can lead to the degradation of the network performance. We'll introduce this behaviour and. We'll propose a new profile to assess the impact on the performance of MANETs: energy, end-to-end delay, routing packets and the packets rate. The Results of simulations using OLSR and AODV protocols have shown that energy-based selfishness is a big problem and could affect the performance in MANETS depending on the mobility of nodes, size and density of the network. We'll try to prove that the selfish behaviour can be used to impact quality of service (QoS) and security in MANETS. Therefore, we need a comprehensive mechanism to cope with this behaviour to isolate selfishness nodes and we have planned to publish it in the future work as a new strategy based on game theory to encourage nodes to cooperate.