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Connectivity maintenance in IoT-based mobile networks: approaches and challenges

Akram Vahid Khalilpour, Challenger Moharram

Annals of Computer Science and Information Systems

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2021

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Vol. 26

145--149

EN

Connectivity is an important requirement in almost all IoT-based wireless networks. The multi-hop networks use intermediate nodes to create a communication path between other nodes. Hence losing some nodes may cut off all communication paths between other active nodes. Generally, the connectivity of a partitioned network can be restored by adding new or activating redundant nodes, moving available nodes to the new location, and increasing the wireless communication range of nodes. The restoration problem may have many constraints and sub-problems. The network may initially be disconnected, the nodes may be heterogeneous, reliable connections may be required between the nodes, we may have unreachable locations in the network area to put the new nodes or move exciting nodes, more than one node may fail at the same time and the expected coverage area may complicate the connectivity restoration problem. In this paper, we study the main challenges and methods of connectivity restoration in IoT-based wireless networks.

2

Advanced surface vehicles collision risk reduction system

Wydro K., Demozzi A., Jarkowski J.

Archives of Transport System Telematics

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2017

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Vol. 10, iss. 4

42--46

EN

An idea of the innovative enhanced vehicle collision preventing system is presented. The system is based on usage of real-time information about vehicles mutual positions, trajectories and movement, which will be collected by mobile sensor network created ad-hoc by vehicles entering a potentially colliding area. The system will particularly consider vehicles movements dynamics, procedures of secure approaching and passing-by processes as well as remote warnings about traffic obstacles ahead. Premises and assumption for possible procedures and algorithms referred to such a network functionalities involving dispersed mechanism of drivers behaviours coordination is analysed, taking into account also some possible and allowed level of automation of the autonomous control an steering of the vehicle. Moreover, a possibility of system cooperation with various brand contemporary equipment of ITS Advanced Driver Assistance Systems type is analyzed. Results of analysis will be presented first of all to traffic participants and to appropriate traffic management services.

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Seismic Monitoring of Poland - Description and Results of Temporary Seismic Project with Mobile Seismic Network

Trojanowski J., Plesiewicz B., Wiszniowski J.

Acta Geophysica

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2015

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Vol. 63, no. 1

17--44

EN

The paper describes a temporary seismic project aimed at developing the national database of natural seismic activity for seismic hazard assessment, officially called “Monitoring of Seismic Hazard of Territory of Poland” (MSHTP). Due to low seismicity of Poland, the project was focused on events of magnitude range 1-3 in selected regions in order to maximize the chance of recording any natural event. The project used mobile seismic stations and was divided into two stages. Five-year measurements brought over one hundred natural seismic events of magnitudes ML range 0.5-3.8. Most of them were located in the Podhale region in the Carpathians. Together with previously recorded events this made it possible to conduct a preliminary study on ground motion prediction equation for this region. Only one natural event, of magnitude ML = 3.8, was recorded outside the Carpathians in a surprising location in central-west Poland.

4

How to CaIculate Call Blocking in One GSM Cell with Intra-cell Traffic

Šuh T., Mitić D., Markov Ž., Lebl A.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 12

126-129

EN

In this paper we present the influence of the connections between GSM users, situated in the same base station (intra-cell connections), on the increase of traffic loss. The utilization of Erlang model in this case gives underestimated loss. We suggest one known queuing model for the more accurate calculation in this case. Several numerical examples prove that traffic loss increases with the increase of intra-cell traffic in total traffic and with the increase of the number of channels in the group. The results are confirmed by the simulation.

PL

W artykule opisano wpływ połączenia miedzy odbiorcami (połączenia intra-cell)stacji GSM na zwiększenie strat w komunikacji. Wykorzystanie do tego celu modelu Erlanga daje przeszacowanie strat. Zamiast tego zaproponowano model kolejkowania.

5

SODMRP: Stable On-Demand Multicast Routing Protocol

Jamali S., Mohammadzadeh H.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 3b

219-222

EN

A mobile ad hoc network (MANET) is a dynamically reconfigurable wireless network that does not have a fixed infrastructure.The grouporiented services are one of the important application classes that are adopted by mobile ad hoc networks (MANETs). To support such services, multicast routing is used. But, stable multicast routing is difficult in MANETs due to limited resources and mobility of nodes. This paper proposes an energy-aware approach to develop a stable multicast routing protocol. By offering some modifications over ODMRP protocol, we involve nodes’ energy information in the proposed protocol, to increase routes stability. Simulation results show that the proposed protocol improves route stability and hence leads to more packet delivery rate (PDR), more throughput and longer route life time, in compare with ODMRP.

PL

Mobilne bezprzewodowe sieci ad-hoc MANET nie mają stałej infrastruktury. W artykule zaproponowano stabilny protokół przesyłania grupowego informacji umożliwiający zwiększenie szybkości komunikacji pakietowej.

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Efficient Dynamic Data Encryption Algorithm for Mobile Ad Hoc Network

Zhang L., Wu Q., Hu Y.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 9b

42-46

EN

Two proper threshold broadcast encryption schemes are proposed for the mobile ad hoc network. The initial scheme achieves constant size private keys and O(n-t)-size ciphertexts. Under n+1-Decision Bilinear Diffie-Hellman Exponent (n+1-BDHE) assumption, it is provable security in the selective-identity model. Based on the dual system encryption, we propose our main construction. It also has constant size private keys and O(nt)- size ciphertexts. But it achieves full security under the static assumptions which are more natural than them in the existing schemes.

PL

W artykule zaprezentowano dwie metody szyfrowania danych w mobilnych sieciach Ad Hoc.

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Bidirectional and RO Methods for Analysis of Stream-Intensive Applications over Mobile IP Network

Malekian R., Abdullah A. H.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 3b

210-213

EN

These Applications such as voice over IP present many challenges to the design of mobile networks. The mobile networks are constantly changing and the latest devices like smart phones, mobile enabled laptops such as Windows Mobile and the Windows Phone are truly able to delivering on any mobile broadband. Therefore, the Internet service providers must provide enhanced routing methods for delivering a streamintensive traffic to the customers. This paper focuses on performance evaluation of mobile IPv6 routing methods. This evaluation is based on end-toend delay, packet delay variation, and IPv6 traffic dropped.

PL

Mobilne sieci ulegają stałym zmianom i nowoczesne urządzenia mobilne jak smarfony czy tablety są w stanie dopasować się do tych zmian. Dlatego zarządzający serwisem Internetowym powinien wprowadzać ulepszone metody dostarczania strumienia informacji. W artykule analizowano możliwości ulepszenia systemu mobilnego IPv6.