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Security is one of the major challenges in the design and implementation of protocols for mobile ad hoc networks (MANETs). In such systems, the cooperation between nodes is one of the important principles being followed in the current research works to formulate various security protocols. Many existing works assume that mobile nodes will follow prescribed protocols without deviation. However, this is not always the case, because these networks are subjected to a variety of malicious attacks. Since there are various models of attack, trust routing scheme can guarantee security and trust of the network. The purpose of this paper is to propose a novel trusted routing model for mitigating attacks in MANETs.

The proposed model incorporates the concept of trust into the MANETs and applies grey relational analysis theory combined with fuzzy sets to calculate a node’s trust level based on observations from neighbour nodes’ trust level, these trust levels are then used in the routing decision-making process.

In order to prove the applicability of the proposed solution, extensive experiments were conducted to evaluate the efficiency of the proposed model, aiming at improving the network interaction quality, malicious node mitigation and enhancements of the system’s security.

The proposed solution in this paper is a new approach combining the fundamental basics of fuzzy sets with the grey theory, where establishment of trust relationships among participating nodes is critical in order to enable collaborative optimisation of system metrics. Experimental results indicate that the proposed method is useful for reducing the effects of malicious nodes and for the enhancements of system’s security.

There are two types of medium access control (MAC) layer power‐saving (PS) protocols for IEEE 802.11‐based mobile ad hoc networks: synchronous and asynchronous ones. This paper seeks to propose a hybrid PS protocol to take advantages of both types of protocols.

The protocol utilizes the concept of dual‐channel and dual‐transmission‐range clustering. It divides all the hosts into clusters. Each cluster has a head and all the heads are organized as a virtual backbone to help route data. The protocol also utilizes the cluster head dismissal mechanism to avoid the ever‐increasing of cluster heads and to adapt to topology changing.

Simulation results demonstrate that the proposed protocol is more power‐efficient and more scalable than related protocols.

The proposed protocol is applicable to MANETs composed of hosts with single IEEE 802‐11 network interface card.

Internet and GSM have become the dominant designs for information and communication technology (ICT) industries in the late 1990s. Internet protocol (IP) is the dominant standard for cost effective networking and new interactive broadband services. GSM (2G) is currently the dominant cellular technology and it is the basis of GSM, GPRS (2.5G) and UMTS (3G), the GSM‐continuum of standards. The marriage of broadband internet and mobile has created open questions on which are the future winning wireless standards. Will mobile internet be based on the GSM‐continuum or on US wireless developments such as WLAN and WiMAX? In longer time‐scale the Mobile Ad‐hoc Network (MANET) which does not use any preinstalled communications infrastructure may also become a cost‐effective challenger to infrastructure based networks. The paper seeks to address these issues.

The paper elaborates these questions with the aim to provide an analytically clarifying conceptualisation of the competitive relationships between 3G, WLAN/WiMAX and the emerging MANET opportunities both in network and application perspectives. By considering the interaction of the possible competitive regimes we analyze the disruptive capabilities of new solutions to become substitutes to the existing ones.

There are a number of open issues in the WLAN/WiMAX and MANET architectures, which require further work and global standardization. For the while, the integration of the personal applications to the GSM continuum seems to be the most potential approach to import internet to the mobile world. However, there is no winner yet, and the author strongly believes that a new wave of innovations may come around these lines and that these developments will also change the mobile technology and services landscape.

The paper contributes with a systemantic analysis of the competition between 3G, WLAN/WiMAX and ad hoc network technologies. A novelty in the analysis is that it incorporates both network access technologies and applications.

Many clustering protocols for mobile ad hoc networks (MANETs) have been proposed in the literature. With only one exception so far (1), all these protocols are proactive, thus wasting bandwidth when their function is not currently needed. To reduce the signalling traffic load, reactive clustering may be employed.We have developed a clustering protocol named “On‐Demand Group Mobility‐Based Clustering” (ODGMBC) (2), (3) which is reactive. Its goal is to build clusters as a basis for address autoconfiguration and hierarchical routing. In contrast to the protocol described in ref. (1), the design process especially addresses the notions of group mobility and of multi‐hop clusters in a MANET. As a result, ODGMBC maps varying physical node groups onto logical clusters. In this paper, ODGMBC is described. It was implemented for the ad hoc network simulator GloMoSim (4) and evaluated using several performance indicators. Simulation results are promising and show that ODGMBC leads to stable clusters. This stability is advantageous for autoconfiguration and routing mechansims to be employed in conjunction with the clustering algorithm.

This study aims to evaluate the direct trust value for each node and calculate the trust value of all nodes satisfying the condition and update the trust value and value each trust update interval for a secure and efficient communication between sender and destination node. Hence, a Trusted Secure Geographic Routing Protocol (TSGRP) has been proposed for detecting attackers (presence of the hacker), considering the trust value for a node produced by combining the location trusted information and the direct trusted information.

Amelioration in the research studies related to mobile ad hoc networks (MANETs) and wireless sensor networks has shown greater concern in the presence of malicious nodes, due to which the delivery percentage in any given network can degrade to a larger extent, and hence make the network less reliable and more vulnerable to security.

TSGRP has outperformed the conventional protocols for detecting attacks in MANET. TSGRP is establishing a trust-based secure communication between the sender and destination node. The evaluated direct trust value is used after the transmission of route-request and route-reply packets, to evaluate the direct trust value of each node and a secure path is established between the sender and the destination node. The effectiveness of the proposed TSGRP is evaluated through NS-2 simulation.

The simulation results show the delay of the proposed method is 92% less than PRISM approach and the overhead of the proposed TSGRP approach is 61% less than PRISM approach.

The decoupling and asynchrony properties of the content‐based publish‐subscribe paradigm makes it very appealing for dynamic wireless networks, like those that often occur in pervasive computing scenarios. Unfortunately, most of the currently available content‐based publish‐subscribe middleware do not fit the requirements of such extreme scenarios, in which the network is subject to very frequent topological reconfigurations due to mobility of nodes. In this paper we propose a protocol for content‐based message dissemination tailored to Mobile Ad Hoc Networks (MANETs) showing frequent topological changes. Message routing occurs without the support of any network‐wide dispatching infrastructure thus eliminating the need of maintaining such infrastructure on top of a physical network continuously changing its topology. The paper reports an extensive simulation study that confirms the suitability of the proposed approach along with a stochastic analysis of the central mechanism adopted by the protocol.

The purpose of this paper is to design an efficient on-demand routing protocol for mobile ad hoc networks (MANETs) which combines greedy forwarding and backtracking.

It uses a hybrid approach. It uses greedy approach to determine a route from source to the destination. If the greedy approach fails, then it uses a backtracking approach. Combining greedy and backtracking approaches results in a more efficient protocol.

A new routing algorithm for MANETs which performs better than some of the existing algorithms.

A major limitation of this work is that the authors did not implement the protocol on a test bed and evaluated the performance. They neither had the infrastructure nor the resources to actually implement the protocol. Instead, like most of the researchers, they evaluated the performance of their protocol based on extensive simulation. The mobility model, the area of deployment and the density of nodes chosen to simulate the protocol are consistent with what many of the other researchers have done. Intuitively, the authors’ protocol, as the performance evaluation indicates, is likely to perform well in small networks.

The authors did not implement the protocol on a test bed to evaluate the performance of the protocol. The authors used simulation to study the performance of their protocol. Their simulation model is similar to many of the research works published in the literature.

To the authors’ knowledge, no other paper has combined the greedy and backtracking approach to design a routing protocols for MANETs.

This paper aims to present an approach for a bio‐inspired decentralization topology control mechanism, called force‐based genetic algorithm (FGA), where a genetic algorithm (GA) is run by each holonomic autonomous vehicle (HAV) in a mobile ad hoc network (MANET) as software agent to achieve a uniform spread of HAVs and to provide a fully connected network over an unknown geographical terrain. An HAV runs its own FGA to decide its next movement direction and speed based on local neighborhood information, such as obstacles and the number of neighbors, without a centralized control unit or global knowledge.

The objective function used in FGA is inspired by the equilibrium of the molecules in physics where each molecule tries to be in the balanced position to spend minimum energy to maintain its position. In this approach, a virtual force is assumed to be applied by the neighboring HAVs to a given HAV. At equilibrium, the aggregate virtual force applied to an HAV by its neighbors should sum up to zero. If the aggregate virtual force is not zero, it is used as a fitness value for the HAV. The value of this virtual force depends on the number of neighbors within the communication range of R_com and the distance among them. Each chromosome in our GA‐based framework is composed of speed and movement direction. The FGA is independently run by each HAV as a topology control mechanism and only utilizes information from neighbors and local terrain to make movement and speed decisions to converge towards a uniform distribution of HAVs. The authors developed an analytical model, simulation software and several testbeds to study the convergence properties of the FGA.

The paper finds that coverage‐centric, bio‐inspired, mobile node deployment algorithm ensures effective sensing coverage for each mobile node after initial deployment. The FGA is also an energy‐aware self‐organization framework since it reduces energy consumption by eliminating unnecessary excessive movements. Fault‐tolerance is another important feature of the GA‐based approach since the FGA is resilient to losses and malfunctions of HAVs. Furthermore, the analytical results show that the authors' bio‐inspired approach is effective in terms of convergence speed and area coverage uniformity. As seen from the experimental results, the FGA delivers promising results for uniform autonomous mobile node distribution over an unknown geographical terrain.

The proposed decentralized and bio‐inspired approach for autonomous mobile nodes can be used as a real‐time topology control mechanism for commercial and military applications since it adapts to local environment rapidly but does not require global network knowledge.

Abstract‐CEDAR protocol is a distributed routing protocol oriented to Quality of Service (QoS) support in MANET, and bandwidth is the QoS parameter of interest in this protocol. However, without energy efficiency consideration, earlier node failure will occur in overloaded nodes in CEDAR, and in turn may lead to network partitioning and reduced network lifetime. The storage and processing overhead of CEDAR is fairly high because too many kinds of control packets are exchanged between nodes and too much state information needs to be maintained by core nodes. The routing algorithm depends fully on the link state information known by core nodes. But the link state information may be imprecise, which will result in route failures. In this paper, we present an improved energy efficient CEDAR protocol, and propose a new efficient method of bandwidth calculation. Simulation results show that the improved CEDAR is efficient in terms of packet delivery ratio, throughput and mean‐square error of energy.

Pervasive environments are mostly based on the ad hoc networking paradigm and are characterized by ubiquity in both users and devices and artifacts. In these inherently unstable conditions and bearing in mind the resource’s limitations that are attributed to participating devices, the deployment of Knowledge Management techniques is considered complicated due to the particular requirements. Security considerations are also very important since the distribution of knowledge information to multiple locations over a network, poses inherent problems and calls for advanced methods in order to mitigate node misbehaviour and in order to enforce authorized and authenticated access to this information. This paper addresses the issue of secure and distributed knowledge management applications in pervasive environments. We present a prototype implementation after having discussed detailed design principles as far as the communications and the application itself is regarded. Robustness and lightweight implementation are the cornerstones of the proposed solution. The approach we have undertaken makes use of overlay networks to achieve efficiency and performance optimization, exploiting ontologies. The work presented in this paper extends our initial work to tackle this problem, as this was described in (28).