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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.

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.

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.

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.

Multimedia applications such as digital audio and video have stringent quality of service (QoS) requirement in mobile ad hoc network. To support wide range of QoS, complex routing protocols with multiple QoS constraints are necessary. In QoS routing, the basic problem is to find a path that satisfies multiple QoS constraints. Moreover, mobility, congestion and packet loss in dynamic topology of network also leads to QoS performance degradation of protocol.

In this paper, the authors proposed a multi-path selection scheme for QoS aware routing in mobile ad hoc network based on fractional cuckoo search algorithm (FCS-MQARP). Here, multiple QoS constraints energy, link life time, distance and delay are considered for path selection.

The experimentation of proposed FCS-MQARP is performed over existing QoS aware routing protocols AOMDV, MMQARP, CS-MQARP using measures such as normalized delay, energy and throughput. The extensive simulation study of the proposed FCS-based multipath selection shows that the proposed QoS aware routing protocol performs better than the existing routing protocol with maximal energy of 99.1501 and minimal delay of 0.0554.

This paper presents a hybrid optimization algorithm called the FCS algorithm for the multi-path selection. Also, a new fitness function is developed by considering the QoS constraints such as energy, link life time, distance and delay.

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.

Many applications of mobile ad hoc networks require real‐time data consistency among moving nodes within a geographical area of interest to function correctly, such as those that support disaster recovery and battlefield command and control. While it is operationally desirable to maintain data consistency among nodes within a large geographical area, the time and network resources required to propagate state changes to all nodes place practical limits on network size. This paper aims to investigate this issue.

This paper investigates the notion of location‐based data consistency in mobile ad hoc networks, and analyzes the tradeoff between data consistency and timeliness of data exchange among nodes within a location‐based group in a geographical area of interest.

Using a Petri net performance model, performance characteristics of location‐based data consistency maintenance algorithms are analyzed and design conditions under which the system can tradeoff consistency for timeliness (reflecting the response time to propagate a state change) while satisfying the imposed data consistency requirement, when given a set of parameters characterizing the application in the underlying mobile ad hoc network are identified.

The system designer can deploy the optimal area size identified in the analysis for maximizing membership and data consistency based on the “I am alive” beaconing interval used at runtime while satisfying the response time requirement for propagating a state change.

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.

Quality communication is a big challenge in mobile ad hoc networks because of a restricted environment for mobile devices, bandwidth-constrained radio connections, random mobility of connected devices, etc. High-quality communication through wireless links mainly depends on available bandwidth, link stability, energy of nodes, etc. Many researchers proposed stability and link quality methods to improve these issues, but they still require optimization. This study aims to contribute towards better quality communication in temporarily formed networks. The authors propose the stable and bandwidth aware dynamic routing (SBADR) protocol with the aim to provide an efficient, stable path with sufficient bandwidth and enough energy hold nodes for all types of quality of service (QoS) data communication.

The proposal made in this work used received signal strength from the media access control (MAC) layer to estimate the stability of the radio connection. The proposed path stability model combines the stability of the individual link to compute path stability. The amount of bandwidth available for communication at a specific time on a link is defined as the available link bandwidth that is understood as the maximum throughput of that link. Bandwidth as a QoS parameter ensures high-quality communication for every application in such a network. One other improvement, towards quality data transmission, is made by incorporating residual energies of communicating and receiving nodes in the calculation of available link bandwidth.

Communication quality in mobile ad hoc network (MANET) does not depend on a single parameter such as bandwidth, energy, path stability, etc. To address and enhance quality communication, this paper focused on high impact factors, such as path stability, available link bandwidth and energy of nodes. The performance of SBADR is evaluated on the network simulator and compared with that of other routing protocols, i.e. route stability based QoS routing (RSQR), route stability based ad-hoc on-demand distance vector (RSAODV) and Ad-hoc on-demand distance vector (AODV). Experimental outcomes show that SBADR significantly enhanced network performance in terms of throughput, packet delivery ratio (PDR) and normalized control overhead (NCO). Performance shows that SBADR is suitable for any application of MANET having random and high mobility.

QoS in MANET is a challenging task. To achieve high-quality communication, the authors worked on multiple network parameters, i.e. path stability, available link bandwidth and energy of mobile nodes. The performance of the proposed routing protocol named SBADR is evaluated by a network simulator and compared with that of other routing protocols. Statistical analysis done on results proves significant enhancement in network performance. SBADR is suitable for applications of MANET having random and high mobility. It is also efficient for applications having a requirement of high throughput.

SBADR shows a significant enhancement in received data bytes, which are 1,709, 788 and 326 more in comparison of AODV, RSAODV and RSQR, respectively. PDR increased by 21.27%, 12.1%, 4.15%, and NCO decreased by 9.67%, 5.93%, 2.8% in comparison of AODV, RSAODV and RSQR, respectively.

Outcomes show SBADR will perform better with applications of MANET such as disaster recovery, city tours, university or hospital networks, etc. SBADR is suitable for every application of MANET having random and high mobility.

This is to certify that the reported work in the paper entitled “SBADR: stable and bandwidth aware dynamic routing protocol for mobile ad hoc network” is an original one and has not been submitted for publication elsewhere. The authors further certify that proper citations to the previously reported work have been given and no data/tables/figures have been quoted verbatim from the other publications without giving due acknowledgment and without permission of the author(s).

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.