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Video transmission effectiveness in the Ad Hoc network is becoming important recently, if different routing protocols are applied. Some researchers conclude that the reactive protocols are better for file transfer protocol (FTP) and constant bit rate (CBR) or hypertext transfer protocol (HTTP) transmission in an Ad Hoc wireless network but the performance report of video transmission is not much. This study adopts Qualnet (Network Simulator) as a simulation tool for environmental designing and performance testing, and employs an experimental design with eight groups. Our experiment shows that: (1) The performance of AODV (reactive) protocol is better than DSDV, ZRP and DSR when the transmission load has only one video stream; (2) Proactive (DSDV) and Hybrid protocols (ZRP) are better for a smaller Ad Hoc network when it transmits a video stream with some applications (VoIP, FTP and CBR). We conclude that packet loss rate is sensitive to the quality of video transmission and it has negative relationship with Peak Signal‐to‐Noise Ratio (PSNR) value. In addition, our experiment also shows that PSNR is a simple Metric for the performance evaluation of video transmission.

This paper aims to propose a system for automatically forming ad hoc networks using mobile phones and battery-powered wireless routers for emergency situations. The system also provides functions to send emergency messages and identify the location of victims based on the network topology information.

Optimized link state routing protocol is used to instantly form an ad hoc emergency network based on WiFi signals from mobile phones of the victims, backup battery-powered wireless routers preinstalled in buildings and mobile devices deployed by search and rescue teams. The proposed system is also designed to recover from partial crash of network and nodes lost.

Experimental results demonstrate the effectiveness of the proposed system in terms of battery life, transmission distance and noises.

A novel message routing schedule is proposed for conserving battery life. A novel function to estimate the location of a mobile device which sent an emergency message is proposed in this paper.

Compared to the traditional wireless network, the multi‐hop ad hoc wireless network is self‐configurable, dynamic, and distributed. During the past few years, many routing protocols have been proposed for this particular network environment. While in wired and optical networks, multi‐protocol label switching (MPLS) has clearly shown its advantages in routing and switching such as flexibility, high efficiency, scalability, and low cost. However MPLS is complex and does not consider the mobility issue for wireless networks, especially for ad hoc wireless networks. This paper migrates the label concept into the ad hoc network and provides a framework for the efficient label routing protocol(LRP) in such a network. The MAC layer is also optimized with LRP for shorter delay, power saving, and higher efficiency. The simulation results show that the delay is improved significantly with this cross‐layer routing protocol.

Secure communication is very important for computer networks. Thereby, authentication is one of the most eminent preconditions. In ad hoc networks, common authentication schemes are not applicable since public key infrastructures with a centralized certification authority are hard to deploy in ad hoc networking environments. This paper aims to investigate these issues.

In order to overcome these issues, the paper proposes and evaluates a security concept based on a distributed certification facility. Thereby, a network is divided into clusters with one special head node each. These cluster head nodes perform administrative functions and hold shares of a network key used for certification. New nodes start to participate in the network as guests; they can only become full members with a network‐signed certificate after their authenticity has been warranted by some other members. Access to resources and services within the ad hoc network is controlled using authorization certificates.

The feasibility of this concept was verified by simulations. Three different models for node mobility were used in order to include realistic scenarios as well as to make the results comparable to other work. The simulation results include an evaluation of the log‐on times, availability, and communication overhead.

The paper introduces a cluster‐based architecture to realize a distributed public key infrastructure that is highly adapted to the characteristics of ad hoc networks.

Although wireless grids have been originally thought of as isolated processing clusters, the possibility of their approaching – and connecting to – a fixed network allows for a huge expansion of their processing power, due to the resources available in wired grids potentially accessible through such a network. The interoperation of mobile ad hoc grids and resources available in wired grids is, however, a problem still to be tackled in the literature. The purpose of this paper is to tackle this problem.

A prototype is developed to demonstrate the feasibility of the interoperation between wireless and wired grids, thus providing a basis for the development of novel applications that can build on this interoperation.

The outcome of the paper comprises the analysis of the necessary requirements for the interoperation between wireless and wired grids, the proposal of two different interoperation approaches, and the provision of a qualitative assessment of the implications of these approaches.

There are many points that the authors intend to address as future work. First, they are aware of the need for performing some quantitative analyses of their proxy implementations. Second, they intend to investigate the possibility of mobile ad hoc grids to process tasks coming from wired grids. Third, they are interested in allowing the submission of tasks that present interdependencies (workflows) from mobile devices in the mobile ad hoc grid.

The paper investigates the interoperation of wireless and wired grids. Such an interoperation may open new perspectives of practical use of wireless devices in scenarios such as emergency response networks and field research systems, to name a few.

The paper provides a first step into the interoperation of wireless and wired grids, thus yielding a basis for the development of novel applications that can build upon this interoperation. This is believed to be of interest to both the grid and mobile computing communities.

The paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, this paper aims to propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system to distribute to solve the problem of control and communication failure at the same time.

In the paper, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the air-ground integrated wireless ad hoc network-integrated system.

The results show that the integrated system has good robustness and fault tolerance performance indicators for flight control and wireless signal transmission when confronted with external disturbances, internal actuator failures and wireless network associated failures and the flight control curve of the quadrotor unmanned aerial vehicle (UAV) is generally smooth and stable, even if it encounters external disturbances and actuator failures, its fault tolerance performance is very good. Then in the range of 400–800 m wireless communication distance, the success rate of wireless signal loop transmission is stable at 80%–100% and the performance is at least relatively improved by 158.823%.

This paper takes the air-ground integrated wireless ad hoc network-integrated system as the research object, based on the robust fault-tolerant control algorithm, the authors propose a distributed robust H_∞ adaptive fault-tolerant control algorithm suitable for the system and through the Riccati equation and linear matrix inequation method, the designed distributed robust H_∞ adaptive fault-tolerant controller further optimizes the fault suppression factor γ, so as to break through the limitation of only one Lyapunov matrix for different fault modes to distribute to solve the problem of control and communication failure at the same time.

Routing in ad hoc networks faces significant challenges due to node mobility and dynamic network topology. In this work we propose the use of mobility prediction to reduce the search space required for route discovery. A method of mobility prediction making use of a sectorized cluster structure is described with the proposal of the Prediction based Location Aided Routing (P‐LAR) protocol. Simulation study and analytical results of P‐LAR find it to offer considerable saving in the amount of routing traffic generated during the route discovery phase.

In mobile ad hoc networks, many routing protocols use broadcast mechanism to find route whereas one of the wireless network challenges is the bandwidth optimisation. This mechanism increases the control overhead and consumes bandwidth and energy. The overhead penalty increases with the density and the network size. Thus is important to reduce the number of participants in that mechanism. One of the used solutions consists of determining clusterheads nodes. In this paper, we propose an algorithm for choosing clusterheads (SRCAC). Each node in the network broadcasts its ID, status and election index. The election index is a combination of potentiality index and stability index. The potentiality index is a linear combination of the mobile resources like processor speed, RAM and ROM memories. The stability index shows the cluster life time. Then, we use SRCAC to build clusters. We suggest a backup clusterhead which could become the principal clusterhead when the first breaks down. To improve the reliability of interclusters communications, we build a mesh between gateway and distributed gateway. Moreover, we introduce Quality of Service (QoS) constraints in the ODMRP (On Demand Multicast Routing Protocol) mobility prediction version.We compare our algorithm with the WCA (Weighted Clustering Algorithm for Mobile Ad hoc Networks) algorithm in terms of clusterheads. The results show that our algorithm performs better than the WCA and, finally, the deterioration of the performances imposed by the constraints on this ODMRP version is unimportant.

Mobility management for single‐hop cellular networks has received much research attention in the last few years. One of the research challenges for 4G wireless systems is the design of mobility management techniques that integrate cellular and ad‐hoc networks. Currently, there are no structured mobility management schemes for these heterogeneous multi‐hop networks. This paper aims to address these issues.

This paper describes techniques for tracking a mobile node (MN) in an integrated architecture with minimum overhead. This paper proposes group rerouting concept.

The paper implements and evaluates the proposed protocol by using the network simulator (NS‐2). The proposed protocol increases performance compared to broadcasting schemes.

This scheme considers devices with two interfaces only.

The paper proposes a scheme to extend the coverage of cellular base stations by using ad‐hoc devices.

This paper describes techniques for tracking an MN in an integrated architecture with minimum overhead. This scheme is independent of the routing protocol used in a multi‐hop network.

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.