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1
Content available A holistic study on the use of blockchain technology in CPS and IoT architectures maintaining the CIA triad in data communication
Bhattacharjya Aniruddha
International Journal of Applied Mathematics and Computer Science
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2022
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Vol. 32, no. 3
403--413
EN
Blockchain-based cyber-physical systems (CPSs) and the blockchain Internet of things (BIoT) are two major focuses of the modern technological revolution. Currently we have security attacks like distributed denial-of-service (DDoS), address resolution protocol (ARP) spoofing attacks, various phishing and configuration threats, network congestion, etc. on the existing CPS and IoT architectures. This study conducts a complete survey on the flaws of the present centralized IoT system’s peer-to-peer (P2P) communication and the CPS architecture’s machine-to-machine (M2M) communication. Both these architectures could use the inherent consensus algorithms and cryptographic advantages of blockchain technology. To show how blockchain technology can resolve the flaws of the existing CPS and IoT architectures while maintaining confidentiality, integrity, and availability (the CIA triad), we conduct a holistic survey here on this topic and discuss the research focus in the domain of the BIoT. Then we analyse the similarities and dissimilarities of blockchain technology in IoT and CPS architectures. Finally, it is well understood that one should explore whether blockchain technology will give advantages to CPS and IoT applications through a decision support system (DSS) with a relevant mathematical model, so here we provide the DSS with such a model for this purpose.
2
Modelowanie pojęciowe systemów partnerskich w wirtualnej organizacji działań
Tarłowski P.
Zeszyty Naukowe Wyższej Szkoły Informatyki
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2011
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Vol. 10, Nr 2
140-148
PL
W pracy omówiono wybrane problemy tworzenia wspólnych przestrzeni informacyjnej, środowiska wirtualnej współpracy ludzi i wirtualnego współdziałania organizacji, korzystając z modeli systemów partnerskich – P2P. Wśród problemów szczegółowych, zwraca się uwagę na: (1) sposoby koordynacji wymiany zasobów cyfrowych, (2) utrzymywanie systemów partnerskich, które bazuje na procesach dostępu do węzłów sieci partnerskiej. Rozważane problemy są ważne dla modelowania konceptualnego struktur gridowych, co jest potrzebne dla budowy różnorodnych systemów wirtualnej organizacji działań.
EN
The paper discusses some problems of creating a common information space, which is the environment of the virtual collaboration and of people and the virtual cooperation of organizations, using the partner systems - P2P models. Among the detailed problems, attention is paid mainly to: (1) how to coordinate the exchange of digital resources, (2) maintenance of the partner systems based on the processes of access to the partner network nodes. Considered problems are important for conceptual modeling of grid structures, what is needed for the building of various virtual activities organization systems.
3
Content available remote Optimization of p2p-based distributed systems
Walkowiak K., Chmaj G., Kucharzak M., Siwek A., Skowron J.
Journal of Applied Computer Science
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2011
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Vol. 19, nr 1
117-138
EN
Various kinds of distributed systems gain much attention in recent years. One of the most significant example is the Peer-to-Peer (P2P) paradigm widely used in many applications including: file-sharing systems (e.g. BitTorrent), computing systems (e.g. SETI@home), communication systems (e.g. Skype) and many others. In this work we present our latest research related to the problem of P2P-based distributed systems optimization. We consider two following problems: optimization of data distribution P2P systems and optimization of P2P computing systems. For both problems we formulate Integer Programming models. Due to the complexity of these problems, exact methods can be applied only for relatively small instances. Therefore, we propose several heuristic algorithms including tabu search, evolutionary algorithm, constructive heuristic and random approach. Results of extensive numerical experiments show the effectiveness of proposed algorithms in comparison to optimal results yielded by CPLEX solver. The optimization methods presented in this paper can be used for optimization of various P2P systems.
4
Content available remote Resource and service discovery in SOAs: A P2P oriented semantic approach
Di Modica G., Tomarchio O., Vita L.
International Journal of Applied Mathematics and Computer Science
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2011
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Vol. 21, no 2
285-294
EN
An intense standardization process is favouring the convergence of grids and Service Oriented Architectures (SOAs). One of the benefits of such technological convergence is that grid resources and applications can be virtualized by services and offered through the SOA paradigm. In the broad and interoperable scenarios enabled by the SOA, involving the participation of several grid infrastructures across many administrative domains, service discovery can be a serious issue. In this paper we present a P2P-based infrastructure that leverages semantic technologies to support a scalable and accurate service discovery process. The key concept of the presented idea is the creation of an overlay network organized in several semantic groups of peers, each specialized in answering queries pertaining to specific applicative domains. Groups are formed by clustering together peers offering services that are semantically related. The architecture details of the proposed solution are presented. A system prototype has also been implemented and validated through a case study deployed on the PlanetLab testbed.
5
Content available Non-cryptographic methods for improving real time transmission security and integrity
Oryńczak G., Kotulski Z.
Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica
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2011
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Vol. 11, no. 3
71--86
EN
In this paper we present a few non cryptographic methods for improving the security, integrity and reliability of real time services. The methods presented in this paper apply to real time transmitting systems, which are based on the Peer-to-Peer (P2P) model. A basic idea of the first technique is to use agents for detecting steganographic content in packet headers, so packets with suspicious entries in the IP header fields will be blocked or the fields will be erased. The two other presented techniques are based on reputation and trust systems, so trust and reputation basic definitions, types and modelling methods are shown. Also a simple design scheme of using these mechanisms in a P2P real-time data transmitting infrastructure is presented. Additionally, we describe an idea of path selecting technique, which can be used to avoid paths that are susceptible to eavesdropping.
6
Content available remote Damming the Torrent: Adjusting BitTorrent-like Peer-to-Peer Networks to Mobile and Wireless Environments
Eittenberger P. M., Kim S., Krieger U. R.
Advances in Electronics and Telecommunications
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2011
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Vol. 2, no. 3
14--22
EN
Mobile peer-to-peer (P2P) traffic is rapidly growing, but present P2P applications are not specifically designed to operate under mobile conditions. To assess the performance of the prevalent file sharing application BitTorrent in a mobile WiMAX network, we performed a measurement and analysis campaign. In this study, we use the obtained measurement traces to further investigate specific characteristics of this P2P network. In particular, we analyze the distribution of its peer population under mobile conditions and present a general classification scheme for peer populations in BitTorrent-like P2P networks. Further, we propose a simple heuristic to bound the outdegree of BitTorrent-like P2P systems when operating in mobile environments.
7
Content available remote On Distributed Data Processing in Data Grid Architecture for a Virtual Repository
Kuliberda K., Wiślicki J., Kowalski T. M., Adamus R., Kaczmarski K., Subieta K.
Journal of Applied Computer Science
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2010
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Vol. 18, nr 2
25-55
EN
The article describes the problem of integration of distributed, heterogeneous and fragmented collections of data with application of the virtual repository and the data grid concept. The technology involves: wrappers enveloping external resources, a virtual network (based on the peer-topeer technology) responsible for integration of data into one global schema and a distributed index for speeding-up data retrieval. Authors present a method for obtaining data from heterogeneously structured external databases and then a procedure of integration the data to one, commonly available, global schema. The core of the described solution is based on the Stack-Based Query Language (SBQL) and virtual updatable SBQL views. The system transport and indexing layer is based on the P2P architecture.
8
Content available Random Approach to Optimization of Overlay Public-Resource Computing Systems
Chmaj G., Walkowiak K.
International Journal of Electronics and Telecommunications
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2010
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Vol. 56, No. 1
55-61
EN
The growing need for computationally demanding systems triggers the development of various network-oriented computing systems organized in a distributed manner. In this work we concentrate on one kind of such systems, i.e. public-resource computing systems. The considered system works on the top of an overlay network and uses personal computers and other relatively simple electronic equipment instead of supercomputers. We assume that two kinds of network flows are used to distribute the data in the public-resource computing systems: unicast and peer-to-peer. We formulate an optimization model of the system. After that we propose random algorithms that optimize jointly the allocation of computational tasks and the distribution of the output data. To evaluate the algorithms we run numerical experiments and present results showing the comparison of the random approach against optimal solutions provided by the CPLEX solver.
9
Content available Comparison of Evolutionary Algorithm and Heuristics for Flow Optimization in P2P Systems
Kucharzak M., Siwek A., Walkowiak K.
International Journal of Electronics and Telecommunications
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2010
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Vol. 56, No. 2
145-152
EN
Nowadays, many Internet users make use of Peer-to-Peer (P2P) systems to download electronic content including music, movies, software, etc. Growing popularity in P2P based protocol implementations for file sharing purposes caused that the P2P traffic exceeds Web traffic and in accordance with to many statistics, P2P systems produce a more than 50% of the whole Internet traffic. Therefore, P2P systems provide remarkable income for Internet Service Providers (ISP). However, at the same time P2P systems generates many problems related to traffic engineering, optimization, network congestion. In this paper we focus on the problem of flow optimization in P2P file sharing systems. Corresponding to BitTorrent-based systems behaviour, the optimization of P2P flows is very complex and in this work we consider different heuristic strategies for content distribution and moreover we propose a new evolutionary algorithm (EA) for this problem. We compare results of the algorithms against optimal results yielded by CPLEX solver for networks including 10 peers and relation to random algorithm for 100-node systems. According to numerical experiments, the EA provides solutions close to optimal for small instances and all of the heuristics exhibit a superior performance over random search.
10
Analiza systemów peer-to-peer (P2P): właściwości, możliwe zastosowania, otwarte problemy
Popczyk G.
Studia Informatica
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2003
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Vol. 24, nr 3
123-130
PL
W artykule przedstawiono systemy peer-to-peer (P2P) - systemy zdecentralizowane, samoorganizujące się, charakteryzujące się dużą fluktuacją węzłów. Systemy P2P stanowią uzupełnienie, a w wielu przypadkach lepszą alternatywę dla systemów opartych na modelu komunikacji klient-serwer. Celem artykułu jest porównanie podstawowych właściwości istniejących systemów P2P, przedstawienie możliwych zastosowań oraz otwartych problemów badawczych.
EN
This paper presents peer-to-peer (P2P) systems - an example of decentralized, self-organizing, highly dynamic systems. The P2P systems may complement, and in many cases replace the client-server systems. This paper compares the architectures of existing P2P systems, discusses possible applications and open problems.
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