Mobility model

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Mobility models characterize the movements of mobile users with respect to their location, velocity and direction over a period of time. These models play an vital role in the design of Mobile Ad Hoc Networks(MANET). Most of the times simulators play a significant role in testing the features of mobile ad hoc networks. Simulators like (NS, QualNet, etc.) allow the users to choose the mobility models as these models represent the movements of nodes or users. As the mobile nodes move in different directions, it becomes imperative to characterize their movements vis-à-vis to standard models. The mobility models proposed in literature have varying degrees of realism i.e. from random patterns to realistic patterns. Thus these models contribute significantly while testing the protocols for mobile ad hoc networks.

Contents

Background and terminology

The study of large and complex networks is possible by experimenting on a simulator rather than on analytical studies. The relatively new form of networks like Mobile Ad Hoc Networks(MANET), Vehicular Ad Hoc Networks (VANET), etc. are characterized by nodes which are autonomous and dynamic in nature. Thus it becomes very essential to capture their movements so that the corresponding simulations results are nearer to reality. Mobility models are basically classified as stochastic, detailed, Hybrid and Trace based Realistic models. [1]

Mobility models

For mobility modelling, the behavior or activity of a user's movement can be described using both analytical and simulation models. The input to analytical mobility models are simplifying assumptions regarding the movement behaviors of users. Such models can provide performance parameters for simple cases through mathematical calculations. In contrast, simulation models consider more detailed and realistic mobility scenarios. Such models can derive valuable solutions for more complex cases. Typical mobility models include

Metrics for Mobility Models

Mobility model metrics are useful to study the impact of mobility models on the performances of mobile ad hoc networks. Metrics are usually classified as mobility metrics, connectivity graph metrics and protocol performance metrics. [2]

See also

Related Research Articles

Optimized Link State Routing Protocol

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Dynamic Source Routing (DSR) is a routing protocol for wireless mesh networks. It is similar to AODV in that it forms a route on-demand when a transmitting node requests one. However, it uses source routing instead of relying on the routing table at each intermediate device.

Vehicular ad hoc networks (VANETs) are created by applying the principles of mobile ad hoc networks (MANETs) – the spontaneous creation of a wireless network of mobile devices – to the domain of vehicles. VANETs were first mentioned and introduced in 2001 under "car-to-car ad-hoc mobile communication and networking" applications, where networks can be formed and information can be relayed among cars. It was shown that vehicle-to-vehicle and vehicle-to-roadside communications architectures will co-exist in VANETs to provide road safety, navigation, and other roadside services. VANETs are a key part of the intelligent transportation systems (ITS) framework. Sometimes, VANETs are referred as Intelligent Transportation Networks. They are understood as having evolved into a broader "Internet of vehicles". which itself is expected to ultimately evolve into an "Internet of autonomous vehicles".

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B.A.T.M.A.N.

The Better Approach to Mobile Ad-hoc Networking (B.A.T.M.A.N.) is a routing protocol for multi-hop mobile ad hoc networks which is under development by the German "Freifunk" community and intended to replace the Optimized Link State Routing Protocol (OLSR).

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The Manhattan mobility model is a guide which leads the driver of a vehicle on the correct path. It is an urban type of mobility model for vehicular ad-hoc networks (VANET). The Manhattan mobility model uses a "grid road topology. It works optimally where streets are in an organized manner.

The pursue mobility model is a type of spatially-dependent mobility model which is used in ad hoc wireless networks and is also based on RPGM. It represents the tracking process of a mobility node (MN) involving a single targeted node using a Random Waypoint. This technology is often used in law enforcement and signal source tracking.

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In mathematics and telecommunications, stochastic geometry models of wireless networks refer to mathematical models based on stochastic geometry that are designed to represent aspects of wireless networks. The related research consists of analyzing these models with the aim of better understanding wireless communication networks in order to predict and control various network performance metrics. The models require using techniques from stochastic geometry and related fields including point processes, spatial statistics, geometric probability, percolation theory, as well as methods from more general mathematical disciplines such as geometry, probability theory, stochastic processes, queueing theory, information theory, and Fourier analysis.

Opportunistic mobile social networks are a form of mobile ad hoc networks that exploit the human social characteristics, such as similarities, daily routines, mobility patterns, and interests to perform the message routing and data sharing. In such networks, the users with mobile devices are able to form on-the-fly social networks to communicate with each other and share data objects.

OMNeT++ is a modular, component-based C++ simulation library and framework, primarily for building network simulators.

References

  1. Sichitiu, Mihail (2009). Mobility Models for Ad Hoc Networks . London: Springer. pp.  237-254. ISBN   978-1-84800-328-6.
  2. Bai, Fan; Sadagopan, Narayanan; Helmy, Ahmed (2003). ""The IMPORTANT framework for analyzing the Impact of Mobility on Performance Of RouTing protocols for Adhoc NeTworks"" (PDF). Ad Hoc Networks. 1: 383–403 via Elseiver.