Princy Johnson

A survey on probabilistic broadcast schemes for wireless ad hoc networks

Broadcast or flooding is a dissemination technique of paramount importance in wireless ad hoc networks. The broadcast scheme is widely used within routing protocols by a wide range of wireless ad hoc networks such as mobile ad hoc networks, vehicular ad hoc networks, and wireless sensor networks, and used to spread emergency messages in critical scenarios after a disaster scenario and/or an accidents. As the type broadcast scheme used plays an important role in the performance of the network, it has to be selected carefully. Though several types of broadcast schemes have been proposed, probabilistic broadcast schemes have been demonstrated to be suitable schemes for wireless ad hoc networks due to a range of benefits offered by them such as low overhead, balanced energy consumption, and robustness against failures and mobility of nodes. In the last decade, many probabilistic broadcast schemes have been proposed by researchers. In addition to reviewing the main features of the probabilistic schemes found in the literature, we also present a classification of the probabilistic schemes, an exhaustive review of the evaluation methodology including their performance metrics, types of network simulators, their comparisons, and present some examples of real implementations, in this paper.

Improving discovery phase of reactive ad hoc routing protocols using Jaccard distance

Recently, more and more research focus has been directed towards optimum designs for Mobile Ad Hoc Networks (MANETs). In this paper, the authors explore novel broadcasting schemes to improve the discovery phase of reactive routing protocols in MANETs. The objective is to reduce the redundancy of routing packets during the discovery phase of the reactive routing protocols for MANETs. For this purpose, the Jaccard distance is used to select dissimilar nodes during the discovery phase in order to reduce redundancy. Furthermore, it is shown that the Jaccard distance is correlated to the Euclidean distance. The simulation results obtained indicate that the Jaccard distance is a suitable metric for improving the discovery phase of the reactive routing protocols in MANETs.

An evolutionary computation approach for designing mobile ad hoc networks

This paper presents the topological design of ad hoc networks in terms of distances among static nodes and speeds of mobiles nodes. Due to the complexity of the problem and the number of parameters to be considered, a genetic algorithm combined with the simulation environment NS-2 is proposed to find the optimum solution. More specifically, NS-2 provides the fitness function guiding the genetic search. The proposed framework has been tested using a railway scenario in which several static and mobile nodes are interacting. Results show the feasibility of the proposed framework and illustrate the possibility of genetic approach for solving similar application scenarios.

Biased random walks on resource network graphs for load balancing

The currently emerging large-scale complex networks and networks of networks are becoming apparent in the pervasive supply of seamless and transparent access to heterogeneous resources and services such as network domains, applications, services and storage owned by multiple organizations. The dynamics and heterogeneous environments involved, however, pose many challenges for controlling and balancing resource access, composition and deployment across complex grid and network infrastructures. In this paper, a scheme is proposed that gives a distributed load-balancing scheme by generating almost regular resource allocation networks. This network system is self-organized and depends only on local information for load distribution and resource discovery. The in-degree of each node refers to its free resources, and the job assignment and resource discovery processes required for load-balancing are accomplished by using fitted random sampling. Simulation results show that the generated network system provides an effective, scalable, and reliable load-balancing scheme for the distributed resources in grids and networks. The proposed solution is tested with real world data and the performance is tested against a recently reported distributed algorithm for load balancing.

JDER: A history-based forwarding scheme for delay tolerant networks using Jaccard distance and encountered ration

Delay tolerant networks have arisen as a new paradigm of wireless communications in which nodes follow a store-carry-and-forward operation. Unlike other ad hoc networks, mobility of nodes is seen as an interesting feature to deliver information from a source node to a destination node. New forwarding schemes have been proposed to deal with the intermittent communications carried out by nodes in delay tolerant networks. Most forwarding schemes assume that nodes are divided into social communities and the communications are likely to be established between two nodes belonging to the same community. However, the social information is not always available, especially in large environments like cities so it has to be inferred from the history of encounters among nodes. Furthermore, there are cases in which the information has to be widely disseminated throughout the network such as alarm and emergency messages so it has to pass through different communities. In this paper, we propose JDER, a new probabilistic forwarding scheme which guarantees high reachability throughout the network by selecting cut-nodes. JDER is based on two metrics: the history encountered ration and the Jaccard distance, and it has been extensively validated through simulations using 8 different mobility models obtained from real life traces.

Biased random algorithm for load balancing in Wireless Sensor Networks (BRALB)

A Wireless Sensor Network (WSN) consists of large number of small, inexpensive nodes that depend on their sensors, transmission and routing capabilities to collect and disseminate critical data. The energy consumption is a key design criterion for WSN routing algorithms due to the limited availability of energy within network nodes. Hence, energy-efficient routing mechanism is one of the most critical issues in WSNs. In this paper a Biased Random Algorithm for Load Balancing (BRALB) in Wireless Sensor Networks for environment monitoring is proposed. It is based on energy biased random walk. It does not require any global information. It uses probability theory to acquire all the information it needs to route packets based on energy resources in each node. It is shown in this paper by using both simulation that BRALB uses the same energy as the shortest path first routing in cases where the message to be sent is comparatively small in size, with the inquiry message among the neighbors. It is also shown to balance the load (i.e. the packets to be sent) among the neighboring nodes.

Towards scalable and reliable Grid Networks

Improvements in computer and networking technologies over the past decades produced new type of collaborative computing environment called grid networks. Grid is a parallel and distributed computing network system that provides the ability to perform higher throughput computing by taking advantage of many computing resources available in the network. Therefore, to achieve a scalable and reliable grid network system, we need to efficiently distribute the load among the resources accessible on the network. In this paper, we present a distributed and scalable load- balancing framework for grid networks. The generated network system is self-organized and depends only on local information for load distribution and resource discovery. Simulation results show that the generated network system provides an effective, scalable, and reliable load-balancing scheme for the distributed resources accessible on grid networks.

Diversity in Smartphone Usage

Smartphones have become extremely popular today and their popularity continues to grow. Furthermore, they seem to have acquired new patterns of behaviour, based on their ability to access almost limitlessly anywhere and at any time. Despite the increasing popularity of smartphones and their impact on our lifestyle, we have a much sparser understanding of their usage pattern. This paper demonstrates how Big Data analytics could be used to address this knowledge gap by presenting results on behaviour usage analysis from a set of real-life Android smartphone usage data.

An analysis of techniques for opportunistic networking

Opportunistic networks, as opposed to classic ones, rely on human-carried devices. This leads to a high mobility of all the nodes in the network and a very dynamic topology. Developing good forwarding algorithms for optimum routing in opportunistic networks presents a specific set of challenges. The most notable forwarding solutions rely on social human mobility patterns. They depend on several key factors and assumptions. The purpose of this paper is to provide an increased understanding on how these factors can influence routing performance. For this purpose we focus on the number of copies for each generated message, altruism and frequency of exchanged messages. The analysis is based on data collected from a social tracing experiment conducted at the University Politehnica of Bucharest. The setup and implementation of this experiment will also be presented in this paper.

A load balancing scheme for latency optimization in Grid networks

Grid networks take advantage of the resources available by many computers connected within the network to solve large-scale computational problems. To achieve a scalable and reliable Grid network system, the workload needs to be efficiently distributed among the computing resources accessible on the network. Therefore, a distributed and scalable load-balancing scheme for Grid Networks is proposed in this paper. Another objective of this paper is to develop a latency reduction workload distribution protocol for Grid networks. Here, we demonstrate that introducing a latency reduction factor in the random sampling can reduce the effects of communication latency in the Grid network environment. Simulation results show that the resulted network system provides an effective, scalable, and reliable load-balancing scheme for the distributed resources available on Grid networks.