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MILP, Pseudo-Boolean, and OMT Solvers for Optimal Fault-Tolerant Placements of Relay Nodes in Mission Critical Wireless Networks

Chen Qian Matteo, Finzi Alberto, Mancini Toni, Melatti Igor, Tronci Enrico

Fundamenta Informaticae

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2020

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Vol. 174, nr 3/4

229--258

EN

In critical infrastructures like airports, much care has to be devoted in protecting radio communication networks from external electromagnetic interference. Protection of such mission-critical radio communication networks is usually tackled by exploiting radiogoniometers: at least three suitably deployed radiogoniometers, and a gateway gathering information from them, permit to monitor and localise sources of electromagnetic emissions that are not supposed to be present in the monitored area. Typically, radiogoniometers are connected to the gateway through relay nodes. As a result, some degree of fault-tolerance for the network of relay nodes is essential in order to offer a reliable monitoring. On the other hand, deployment of relay nodes is typically quite expensive. As a result, we have two conflicting requirements: minimise costs while guaranteeing a given fault-tolerance. In this paper, we address the problem of computing a deployment for relay nodes that minimises the overall cost while at the same time guaranteeing proper working of the network even when some of the relay nodes (up to a given maximum number) become faulty (fault-tolerance ). We show that, by means of a computation-intensive pre-processing on a HPC infrastructure, the above optimisation problem can be encoded as a 0/1 Linear Program, becoming suitable to be approached with standard Artificial Intelligence reasoners like MILP, PB-SAT, and SMT/OMT solvers. Our problem formulation enables us to present experimental results comparing the performance of these three solving technologies on a real case study of a relay node network deployment in areas of the Leonardo da Vinci Airport in Rome, Italy.

2

Metody wyznaczania zasięgów w warunkach zakłóceń interferencyjnych

Więcek D.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2008

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R. 81, nr 1

11-21

PL

Przedstawiono różne metody wyznaczania zasięgu sieci radiowej w terenie otwartym w obecności wielu zakłóceń interferencyjnych. Omówiono zarówno metody uproszczone i metody przybliżone, jak i metody dokładne. Oceniono celowość i zasadniczy zakres stosowalności metod. Na przykładach pokazano wyniki analiz zasięgu za pomocą różnych metod. Wskazano na konieczność stosowania metod analiz zakłóceń interferencyjnych w coraz aktywniej wykorzystywanym środowisku fal radiowych.

EN

The article shows various methods for estimation radio network coverage in open areas in case of existence of multiple interferences. Different methods were present: simplified methods approximate methods as well as precise methods. Aim and range of application of the methods has been assessed. Examples of the results of coverage calculation were shown. Necessity of taking advantage of the methods for multiple interference assessment in current active radio resources exploitation was indicated.

3

Problematyka bezpieczeństwa radiowych sieci małej prędkości ZigBee

Kubiak Z.

Zeszyty Naukowe. Automatyka / Politechnika Śląska

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2006

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z. 145

119-124

PL

Istotne znaczenie dla rozwoju bezprzewodowych sieci małych prędkości mają prace normalizacyjne, niedawno zakończone opublikowaniem obszernych dokumentów, tzn. IEEE 802.15.4 oraz ZigBee. Te powiązane ze sobą protokoły przewidziane są między innymi dla zastosowań przemysłowych. Ich specyfikacje przedstawiono w opracowaniu, ze szczególnym uwzględnieniem zagadnień bezpieczeństwa.

EN

Standardization works, newly finished by publication of extensive documents i.e. IEEE 802.15.4 and ZigBee, are of great importance for low speed wireless networks development. Those connected together protocols are among other things provided for industrial appliances. Their specifications are presented in the study, taking into consideration especially the security issues.

4

Probabilistyczna generacja selektorów dla algorytmów komunikacji grupowej w sieciach radiowych

Białogrodzki J.

Zeszyty Naukowe. Automatyka / Politechnika Śląska

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2006

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z. 143

11-19

PL

Selektory to obiekty matematyczne wykorzystywane przez kilka zaawansowanych algorytmów komunikacji grupowej dla sieci radiowych. Należy do nich algorytm Chrobak-Gąsieniec-Rytter (CGR), asymptotycznie najefektywniejszy algorytm rozsyłania dla sieci radiowych o nieznanej topologii. Artykuł proponuje prostą, probabilistyczną metodę konstrukcji odpowiednich rodzin selektorów oraz prezentuje wyniki symulacji CGR mających na celu ustalenie, w jakim stopniu wybór konkretnej rodziny wpływa na efektywność algorytmów.

EN

Selectors are mathematical objects used by several advanced group communication algorithms for radio networks. Those include Chrobak-Gąsieniec-Rytter (CGR) algorithm, which is asimptotically the most efficient broadcasting algorithm for unknown topology radio networks. The article proposes randomized method of appropriate selectors and selector families construction, as well as presents the results of CGR simulations carried out to determine whether the choice of selectors family affects the efficiency of algorithms.

5

Trendy w rozwoju sieci radiowych pola walki. Cz. 2

Daniluk P.

Zeszyty Naukowe AON

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2005

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nr 2(59)

114-126

EN

Speed and heterogeneity in technological, social and structural changes having influence upon the battlefield nets create the need of constructing target conception of such a military telecommunication subsystem that could have be conducted for many years to come. Specifying the main trends in changes undergoing in analysed systems is the process leading to the defining of the future battlefield net structures. A particular attention was paid to the analysis of the results and conclusions from the research on development of battlefield net trends in the selected areas of their functioning. One of the development trends is a numerous collection of determinants affecting the planning and using of these military telecommunication nets. The basic determinants include mobility, information flow capacity, resistance to noise and jamming and security. The above factors were analysed, first of all, in aspect of using frequency ranges of the military communication systems. The results of this analysis may be useful for constructing the perspective battlefield net structures. These assumptions are based on two main levels - tactical range areas and higher levels of the battlefield nets command.