International Journal of Computer Networks and Applications

Number V-4-I-1, 2017

1 - 14
Connectivity Based Positioning System for Underground Vehicular Ad Hoc Networks

Authors: Salah Abdel Mageid

Abstract

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Underground vehicular ad-hoc networks are indorsing wireless networks because they can realize many goals such as improving the driving safety and monitoring the emergency alerts in underground environments (i.e., road tunnels). It is necessary for vehicular nodes to recognize their positions to achieve these goals. However, Global Positioning System (GPS) devices cannot operate in underground environments; furthermore, the signal propagation faces many effects such as attenuation, multipath and shadow fading. Traditional distance measurement techniques are inadequate to estimate vehicular node locations in underground environments because the expected measurement errors lead to poor positioning. In this paper, the network connectivity is exploited to estimate vehicular node positions instead of radio ranging methods. This work investigates one of the most important techniques that are based on the network connectivity (i.e., Monte Carlo) and proposes new heuristics that achieve an appropriate position estimation accuracy for vehicular nodes. As the underlying method is predictable, it enables these nodes to know their positions all the time inside underground environments. In addition, an efficient deployment strategy is proposed in this work to well organize reference nodes (i.e., fixed nodes that their positions are preconfigured) inside a road tunnel. The proposed scheme performance is verified by NS2 simulator and compared with the current Monte Carlo localization schemes where the simulation results indicate the superiority of the proposed scheme.

15 - 26
Evaluation of TCP Congestion Control Modus Operandi in Mesh Networks

Authors: Vincent O. Nyangaresi, Solomon. O. Ogara, Silvance O. Abeka

Abstract

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In mesh networks, the sender machine is connected to the receiver machine via multiple paths. Efficient transmissions along these paths require proper link choice so as to quickly deliver the packets the destination. Poor link selection can lead to overutilization of some links while the other redundant links remain underutilized. Over-utilized links experience heavy congestions under peak hours. The transmission control protocol (TCP) employs congestion control algorithms to prevent transmitters from overloading the network with data. These algorithms include slow start, congestion avoidance, fast retransmit and fast recovery. The slow start algorithm is utilized during the initial communication phase while congestion avoidance, fast retransmit and fast recovery are reactionary algorithms one packet loss is detected. This paper aimed to analyze the behavior of TCP under these congestion control algorithms in wired mesh networks. The dimensions that were used for this analysis included three way handshake, packet loss, duplicate acknowledgements, segment retransmissions, recovery, I/O plots and time-sequence plots. The objective of this study was to practically understand how the TCP protocol detects and handles network congestions in mesh networks. To achieve this objective, an experimental research design was employed. It involved the practical design of experimental setups that were used to collect data that was analyzed to provide an explanation of the TCP congestion control mechanisms. The results obtained indicate that the TCP first carries out a three handshake before data transmission can take place. It was also observed that the receipt of three duplicate acknowledgements is interpreted by TCP to be packet loss caused by network congestion. Moreover, it was established that TCP initiates fast retransmit and fast recovery when packet loss is detected. The contribution of this paper lies in the fact that it provided a practical understanding of how TCP detects and reacts to mesh network congestion, a concept that is critical to network administrators in their quest for packet loss prevention over the TCP architecture. Towards the end of the paper, suggestions for developing better ways of congestion handling in mesh networks by use of round trip times as a basis for adaptive congestion detection and control are elaborated.

27 - 34
Big Data Analysis for M2M Networks: Research Challenges and Open Research Issues

Authors: Gurkan Tuna, Resul Das, B. Ramakrishnan, Yilmaz Kilicaslan

Abstract

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In recent years, solutions based on machine-to-machine (M2M) communications have started to support us in many areas of our life and work. However, the amount of data collected by M2M has increased tremendously and surpassed our expectations. This makes it necessary to investigate data mining methodologies and machine learning techniques in order to efficiently utilize large amounts of data gathered by M2M devices. In this paper, we first review existing data mining and machine-learning techniques specifically designed and proposed for M2M networks. Then, we discuss Big Data concept, investigate Big Data analysis techniques, and the importance of Big Data for M2M networks. Finally, we investigate research challenges and open research issues in M2M to provide an insight into future research opportunities.