Connectivity models: A new approach to modeling contacts in opportunistic networks (original) (raw)

A New Realistic Mobility Model for Mobile Ad Hoc Networks

2007 IEEE International Conference on Communications, 2007

Accurately simulating user movements in Mobile Ad hoc Networks (MANETs) is very important to the prediction of actual network and user performance. Therefore, using a realistic mobility model is a crucial factor in enhancing the confidence in the simulation results of these networks. In this paper, we present a new mobility model for MANETs, called Realistic Mobility Model (RMM). In RMM, node velocities and directions of movement are taken from probability distributions that mimic real user mobility behavior. The model is shown to be stationary since it satisfies the conditions of [2]. Simulation results show that RMM produces mobility traces that closely resemble real mobility traces.

MOMOSE: a mobility model simulation environment for mobile wireless ad-hoc networks

2008

This paper describes MOMOSE, a highly flexible and easily extensible environment for the simulation of mobility models. MOMOSE not only allows a programmer to easily integrate a new mobility model into the set of models already included in its distribution, but it also allows the user to let the nodes of the MANET move in different ways by associating any mobility model to any subset of the nodes themselves. The environment allows the user to define and to subsequently use configuration windows, whose content depends on the mobility model, and its GUI includes a simulation window that allows the user to manage and control the execution of a simulation. Moreover, MOMOSE allows the user to simulate the movement of the nodes within a "realistic" environment, where obstacles (such as buildings and barriers) are present and limit the movement of the nodes. Finally, MOMOSE can be easily adapted in order to record, during the simulation time, all the data necessary for the evaluation of the performance of any communication protocol or of any MANET-based application. As far as we know, MOMOSE is the only mobility model simulation environment that has all these features and which is currently available as a free software project.

Mobility Models used in Simulation Area of Mobile Ad Hoc Networks

Advances in Wireless and Mobile Communications (AWMC), 2009

Simulation environments are an important tool for the evaluation of new concepts in networking. The study of mobile ad hoc networks depends on understanding protocols from simulations, before these protocols are implemented in a real-world setting. In the performance evaluation of a protocol for an ad hoc network, the protocol should be tested under realistic conditions including, but not limited to, a sensible transmission range, limited buffer space for the storage of messages, representative data traffic models and realistic movements of the mobile users (i.e. a mobility model). Network simulators emerged as the most common method of evaluating the performance of large and complex networking systems. Existing mobility models vary widely in their realism, from completely artificial to very realistic as well as in their statistical properties. This paper is a survey of mobility models that are used in the simulations of ad hoc networks. We describe several mobility models that represent mobile nodes whose movements are independent of each other (i.e. entity mobility models) and several mobility models that represent mobile nodes whose movements are dependent on each other (i.e. group mobility models). In this paper we provide an overview of those mobility models and their most important properties.

Towards realistic mobility models for mobile ad hoc networks

Proceedings of the 9th annual international conference on Mobile computing and networking - MobiCom '03, 2003

One of the most important methods for evaluating the characteristics of ad hoc networking protocols is through the use of simulation. Simulation provides researchers with a number of significant benefits, including repeatable scenarios, isolation of parameters, and exploration of a variety of metrics. The topology and movement of the nodes in the simulation are key factors in the performance of the network protocol under study. Once the nodes have been initially distributed, the mobility model dictates the movement of the nodes within the network. Because the mobility of the nodes directly impacts the performance of the protocols, simulation results obtained with unrealistic movement models may not correctly reflect the true performance of the protocols. The majority of existing mobility models for ad hoc networks do not provide realistic movement scenarios; they are limited to random walk models without any obstacles. In this paper, we propose to create more realistic movement models through the incorporation of obstacles. These obstacles are utilized to both restrict node movement as well as wireless transmissions. In addition to the inclusion of obstacles, we construct movement paths using the Voronoi diagram of obstacle vertices. Nodes can then be randomly distributed across the paths, and can use shortest path route computations to destinations at randomly chosen obstacles. Simulation results show that the use of obstacles and pathways has a significant impact on the performance of ad hoc network protocols.

Recent advances in mobility modeling for mobile ad hoc network research

Proceedings of the 42nd annual Southeast regional conference, 2004

In this paper, we survey recent advances in mobility modeling for mobile ad hoc network research. The advances include some new mobility models and analysis of older mobility models. First we classify mobility models into three categories according to the degree of randomness. We introduce newly proposed mobility models in each of these categories. Next we discuss analysis for existing mobility models. We describe the analysis work in three parts. The first part is the statistical properties of the most widely used Random Waypoint Model. The second part describes the mobility metrics that aim to capture the characteristics of different mobility patterns. The last part is the impact of mobility models on the performance of protocols. We also describe some possible future work.

Building Realistic Mobility Models for Mobile Ad Hoc Networks

Informatics

A mobile ad hoc network (MANET) is a self-configuring wireless network in which each node could act as a router, as well as a data source or sink. Its application areas include battlefields and vehicular and disaster areas. Many techniques applied to infrastructure-based networks are less effective in MANETs, with routing being a particular challenge. This paper presents a rigorous study into simulation techniques for evaluating routing solutions for MANETs with the aim of producing more realistic simulation models and thereby, more accurate protocol evaluations. MANET simulations require models that reflect the world in which the MANET is to operate. Much of the published research uses movement models, such as the random waypoint (RWP) model, with arbitrary world sizes and node counts. This paper presents a technique for developing more realistic simulation models to test and evaluate MANET protocols. The technique is animation, which is applied to a realistic scenario to produce a model that accurately reflects the size and shape of the world, node count, movement patterns, and time period over which the MANET may operate. The animation technique has been used to develop a battlefield model based on established military tactics. Trace data has been used to build a model of maritime movements in the Irish Sea. Similar world models have been built using the random waypoint movement model for comparison. All models have been built using the ns-2 simulator. These models have been used to compare the performance of three routing protocols: dynamic source routing (DSR), destination-sequenced distance-vector routing (DSDV), and ad hoc n-demand distance vector routing (AODV). The findings reveal that protocol performance is dependent on the model used. In particular, it is shown that RWP models do not reflect the performance of these protocols under realistic circumstances, and protocol selection is subject to the scenario to which it is applied. To conclude, it is possible to develop a range of techniques for modelling scenarios applicable to MANETs, and these simulation models could be utilised for the evaluation of routing protocols.

A survey of mobility models for ad hoc network research

Wireless communications and …, 2002

In the performance evaluation of a protocol for an ad hoc network, the protocol should be tested under realistic conditions including, but not limited to, a sensible transmission range, limited buffer space for the storage of messages, representative data traffic models, and realistic movements of the mobile users (i.e., a mobility model). This paper is a survey of mobility models that are used in the simulations of ad hoc networks. We describe several mobility models that represent mobile nodes whose movements are independent of each other (i.e., entity mobility models) and several mobility models that represent mobile nodes whose movements are dependent on each other (i.e., group mobility models). The goal of this paper is to present a number of mobility models in order to offer researchers more informed choices when they are deciding upon a mobility model to use in their performance evaluations. Lastly, we present simulation results that illustrate the importance of choosing a mobility model in the simulation of an ad hoc network protocol. Specifically, we illustrate how the performance results of an ad hoc network protocol drastically change as a result of changing the mobility model simulated.

A Conceptual Study of Mobility Models in Manet

2018

In general, a Mobile Ad hoc Network (MANET) is a self configuring network of mobile nodes connected by wireless links to form an arbitrary topology without the use of existing infrastructure. In mobile ad hoc network, simulation plays an important role in determining the network characteristics and measuring performance. On the other hand, unrealistic simulation conditions may be misleading, instead of being explanatory. Since MANETs are not currently deployed on a large scale, research in this area is mostly simulation based. Among other simulation parameters, the mobility model plays a very important role in determining the protocol performance in MANET. Thus, it is essential to study and analyze various mobility models. In this paper, we provide survey and classification of existing mobility models. We also discuss various mobility models that exhibit the characteristics of temporal dependency, spatial dependency and geographic constraints. Hence, we attempt to provide an overview of the analysis of mobility modeling.

Recent Advances on the Simulation Models for Ad Hoc Networks: Real Traffic and Mobility Models

2001

In order to provide credible and valid simulation results it is important to built simulation models that accurately represent the environments were ad hoc networks will be deployed. Recent research results have shown that there is a disparity of 30% between protocol performance in real test beds and the one in simulation environments. In this paper we summarize the recent trends on the simulation models for ad hoc networks. First, we provide a survey of the synthetic and real traffic models used in ad hoc network simulation studies. Second, we select a representative of the most used mobility synthetic model, the real pedestrian mobility model, and the real vehicular model (for mixed traffic). We show that the real pedestrian and real vehicular model share common mobility characteristics: a) The transition matrix on both models illustrate that wireless nodes do not move from one location to another at random, but they are rather based on activities (work, shopping, college, gym); b) The dynamic membership property illustrates that nodes join and leave the simulation based on some variable distribution or patterns. Lastly, via simulations we show that when using realistic simulation models the simulation protocol performance closer reflects with the real test bed protocol performance.

A spatial analysis of mobility models: application to wireless ad hoc network simulation

37th Annual Simulation Symposium, 2004. Proceedings.

We quantatively analyze the differences between a realistic mobility model, TRANSIMS, and several synthetic mobility models. New synthetic models were created by modifying the standard random way point model in several ways in an attempt to make it more realistic. We then compare these enhanced models with the TRANSIMS data as well as the random walk and standard random way-point models, using both new spatial based measures as well as network simulation performance. The velocity component and the spatial distributions of nodes over the space were analyzed and compared to the TRANSIMS data in order to be able to more generally analyze the models outside of the context of a network simulation. We also compared the performance of each model in various simulations of a wireless ad hoc network, with a particular emphasis on systematically varying some of the network parameters to determine the sensitivity of each model to differing network conditions. We then relate the simulation results to the more general spatial methods of mobility model comparison that we developed.