Reference Point Group Mobility Model Research Articles

Impact of Correlated Mobility on Delay–Throughput Performance in Mobile Ad Hoc Networks

We extend the analysis of the scaling laws of wireless ad hoc networks to the case of correlated nodes movements, which are commonly found in real mobility processes. We consider a simple version of the Reference Point Group Mobility model, in which nodes belonging to the same group are constrained to lie in a disc area, whose center moves uniformly across the network according to the i.i.d. model. We assume fast mobility conditions and take as a primary goal the maximization of per-node throughput. We discover that correlated node movements have a huge impact on asymptotic throughput and delay and can sometimes lead to better performance than the one achievable under independent nodes movements.

Classification and Evaluation of Mobility Metrics for Mobility Model Movement Patterns in Mobile Ad-Hoc Networks

A mobile ad hoc network is collection of self configuring and adaption of wireless link between communicating devices (mobile devices) to form an arbitrary topology and multihop wireless connectivity without the use of existing infrastructure. It requires efficient dynamic routing protocol to determine the routes subsequent to a set of rules that enables two or more devices to communicate with each others. This paper basically classifies and evaluates the mobility metrics into two categories- direct mobility metrics and derived mobility metrics. These two mobility metrics has been used to measure different mobility models, this paper considers some of mobility models i.e Random Waypoint Model, Reference Point Group Mobility Model, Random Direction Mobility Model, Random Walk Mobility Model, Probabilistic Random Walk, Gauss Markov, Column Mobility Model, Nomadic Community Mobility Model and Manhattan Grid Model.

The Temporal Effect of Mobility on Path Length in MANET

Ad hoc network consists of a set of identical nodes that move freely and independently and communicate among themselves via wireless links. The most interesting feature of this network is that they do not require any existing infrastructure of central administration and hence is very suitable for temporary communication links in an emergency situation. This flexibility, however, is achieved at a price of communication uncertainty induced due to frequent topology changes. In this article, we have tried to identify the system dynamics using the proven concepts of time series modeling. Here, we have analyzed variation of path length between a particular source destination pair nodes over a fixed area for different mobility patterns under different routing algorithm. We have considered four different mobility models—(i) Gauss-Markov mobility model, (ii) Manhattan Grid mobility model and (iii) Random Way Point mobility model and (iv) Reference Point Group mobility model. The routing protocols under which, we carried out our experiments are (i) Ad hoc On demand Distance Vector routing (AODV), (ii) Destination Sequenced Distance Vector routing (DSDV) and (iii) Dynamic Source Routing (DSR). The path length between two particular nodes behaves as a random variable for all mobility models for all routing algorithms. The pattern of path length for every combination of mobility model and for every routing protocol can be well modeled as an autoregressive model of order p i.e. AR(p). The order p is estimated and it is found that most of them are of order unity only. We also calculate the average path length for all mobility models and for all routing algorithms.

Bio-inspired group mobility model for mobile ad hoc networks based on bird-flocking behavior

In this paper, we propose a novel group mobility model for mobile ad hoc networks (MANETs), named as Bird-Flocking Behavior Inspired Group Mobility Model (BFBIGM), which takes inspiration from the mobility of a flock of birds, flying in a formation. Most existing modeling techniques are deficient in successfully addressing many aspects in terms of the application of realistic forces on the movement of mobile nodes (MNs), the interaction of MNs within a group, and collision avoidance within a group and with environmental obstacles. The results obtained through experiments show that in terms of connectivity metrics, such as link duration, BFBIGM performs around 50% better in comparison to the popular existing mobility models like Random Waypoint (RWP) Model (Johnson et al. in Ad hoc networking, Addison-Wesley, Menlo Park, pp. 139–172,2001) and the Reference Point Group Mobility (RPGM) Model (Hong et al. in: Proceedings of the 2nd ACM international workshop on modeling, analysis and simulation of wireless and mobile systems, Seattle, WA, pp. 53–60,1999).

Temporal Modeling of Link Characteristic in Mobile Ad hoc Network

Ad hoc network consists of a set of identical nodes that move freely and independently and communicate among themselves via wireless links. The most interesting feature of this network is that they do not require any existing infrastructure of central administration and hence is very suitable for temporary communication links in an emergency situation. This flexibility, however, is achieved at a price of communication uncertainty induced due to frequent topology changes. In this article, we have tried to identify the system dynamics using the proven concepts of time series modeling. Here, we have analyzed variation of link utilization between any two particular nodes over a fixed area for differentmobility patterns under different routing algorithm. We have considered four different mobility models – (i) Gauss-Markov mobility model, (ii) Manhattan Grid Mobility model and (iii) Random Way Point mobility model and (iv) Reference Point Group mobility model. The routing protocols under which, we carried out our experiments are (i) Ad hoc On demand Distance Vector routing (AODV), (ii) Destination Sequenced Distance Vector routing (DSDV) and (iii) Dynamic Source Routing (DSR). The value of link load between two particular nodes behaves as a random variable for any mobility pattern under a routing algorithm. The pattern of link load for every combination of mobility model and for every routing protocol can be well modeled as an autoregressive model of order p i.e. AR(p). The order of p is estimated and it is found that most of them are of order 1 only.

Interval-Based Localization using RSSI Comparison in MANETs

The knowledge of node positions is essential to many applications of wireless sensor networks. We propose an original model-free technique for localization in mobile ad hoc sensor networks (MANETs). Region constraints are set by a comparison of the received signal strength indicators (RSSIs) at both anchors and nonanchor nodes. The accuracy of this method remains in the way that it overcomes the use of the channel pathloss model. It is thus naturally adapted to nonstationary environments. The proposed approach uses interval analysis and constraints satisfaction techniques to compute accurate locations in a guaranteed way. Simulations are performed on group trajectories of sensors whose movements are generated using a reference point group mobility model. The simulation results confirm the efficiency of the proposed method and show that it outperforms the anchor-based methods in terms of accuracy and estimation errors.

Analytical Studies of Interaction between Mobility Models and Single-Multi Paths Routing Protocols in Mobile Ad Hoc Networks

Mobile ad hoc networks (MANETs) will play a vital role in civilian and military applications where users move around and share information with each other. The movement of users varies depending on the environment, e.g. people may move randomly in different directions (Random Waypoint and Gauss Markov mobility models); or walk, run and drive in two directions in the street (Manhattan Mobility Model); or move as a group (Reference Point Group Mobility model). The interaction between mobility patterns and routing protocols contributes significantly to vary the overall network performance. We build an analytical framework that shows an analysis structure for the overall network performance test. In this framework, we first compare the properties of the mobility models that are designated for MANETs. Second, we measure single path (proactive and reactive) and multipath (proactive and reactive) routing protocols across the mobility models by tuning into TCP and CBR traffic individually. Finally, we examine the performance of each routing protocol across mobility models and discuss the possibility of interaction between them. Most of the previous findings only evaluate the impact of mobility models and single path routing protocols with CBR traffic, whereas a significant finding of this study is that how the interaction between mobility models and single path and multipath routing protocols varies depending on the usage of traffic (TCP and CBR).

Obstacles constrained group mobility models in event-driven wireless networks with movable base stations

In this paper, we propose a protocol for dynamic reconfiguration of ad-hoc wireless networks with movable base stations in presence of obstacles. Hosts are assigned to base stations according to a probabilistic throughput function based on both the quality of the signal and the base station load. In order to optimize space coverage, base stations cluster hosts using a distributed clustering algorithm. Obstacles may interfere with transmission and obstruct base stations and hosts movement. To overcome this problem, we perform base stations repositioning making use of a motion planning algorithm on the visibility graph based on an extension of the bottleneck matching technique. We implemented the protocol on top of the NS2 simulator as an extension of the AODV. We tested it using both Random Way Point and Reference Point Group mobility models properly adapted to deal with obstacles. Experimental analysis shows that the protocol ensures the total space coverage together with a good throughput on the realistic model (Reference Point Group) outperforming both the standard AODV and DSR.

Pause Time Optimal Setting for AODV Protocol on RPGM Mobility Model in MANETs

For the last few years, a number of routing protocols have been proposed and implemented for wireless mobile Ad hoc network. The motivation behind this paper is to discover and study the pause time effects on Ad hoc on Demand Distance Vector (AODV) protocol and find out the node pause time optimal setting for this protocol where Reference Point Group Mobility (RPGM) model uses as a reference model. In order to come across the best performance of a particular routing protocol, there a need to examine a number of parameters with different performance and analyze the optimal setting of that protocol and its network configuration environment. This experiment, the speed is fixed with 20 ms in all scenarios while the pause time is varying from scenario to another to observe the optimal setting of the pause time on protocol’s performance in this configuration. The outcome of the experiment are analyzed with different parameters such as varying number of nodes, increasing connections, increasing pause time and discussed the effects of the pause time. The results have shown that the value of the pause time can be affecting the performance of the protocol. In the experiment, we found that the lower pause time give better performance of the protocol. However, this paper is a part of ongoing research on AODV protocol in link failure. Thus, it is important to figure out the factors which can be involved the performance of the protocol.

Reference Point Group Mobility and Random Waypoint Models in Performance Evaluation of MANET Routing Protocols

Ad hoc networks are characterized by multihop wireless connectivity, frequently changing network topology and the need for efficient dynamic routing protocols plays an important role. We compare the performance of two prominent on-demand routing protocols for mobile ad hoc networks: dynamic source routing (DSR), ad hoc on-demand distance vector routing (AODV). A detailed simulation model with medium access control (MAC) and physical layer models is used to study the interlayer interactions and their performance implications. We demonstrate that even though DSR and AODV share similar on-demand behavior, the differences in the protocol mechanisms can lead to significant performance differentials. In this paper, we examine both on-demand routing protocols AODV and DSR based on packet delivery ratio, normalized routing load, normalized MAC load, average end-to-end delay by varying the node density, network loading, and mobility variations for reference point group mobility and random waypoint models. This framework aims to evaluate the effect of mobility models on the performance of mobile ad hoc networks (MANETs) routing protocols. Our results show that the protocol performance may vary drastically across mobility models and performance rankings of protocols may vary with the mobility models used. This effect can be explained by the interaction of the mobility characteristics with the connectivity graph properties.

Performance analysis of mobility-based d-hop (MobDHop) clustering algorithm for mobile ad hoc networks

This paper presents the performance analysis of the mobility-based d-hop (MobDHop) clustering algorithm, which forms variable-diameter clusters based on node mobility patterns in MANETs. Unlike existing clustering algorithms, the diameter of clusters is not restricted by any preset value. Instead, the diameter of clusters is flexible and determined by the stability of clusters. Nodes which have similar moving patterns are grouped into one cluster in order to achieve maximum cluster stability. Unlike existing multihop clustering algorithms, MobDHop only requires 1-hop neighbourhood knowledge instead of multihop neighbourhood knowledge. This makes MobDHop a truly adaptive, distributed and localized algorithm. This paper first presents the empirical results of MobDHop based on a series of extensive NS-2 simulations. The simulation results show that MobDHop forms clusters which are more stable than those formed by Lowest-ID and Max Connectivity Clustering Algorithm in both Random Waypoint and Reference Point Group Mobility Model. Subsequently, the performance of MobDHop is examined from a theoretical perspective where both the time and message complexities are derived. A comparison of MobDHop and four other clustering algorithms is presented. We show that the overhead incurred by multihop clustering has a similar asymptotic bound as 1-hop clustering while being able to reap the benefits of multihop clusters.