Wyniki wyszukiwania - Biblioteka Nauki

1

SXCCP+: Simple XML Concurrency Control Protocol for XML Database Systems

100%

Jankiewicz K.

Control and Cybernetics

|

2009

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tom Vol. 38, no 1

215-237

EN

Increasing significance and popularity of XML is the main reason why many commercial object-relational database management systems (ORDBMSs) developed XML storage and processing functionality. Additionally, there are new types of specialized database systems known as 'native' XML database systems. As we know, concurrency control is one of the most important mechanisms in DBMSs. Unfortunately, concurrency control mechanisms, which have been used so far in commercially available native XML DBMSs, offer very low degree of concurrency. The development of universal and effective concurrency control protocol for accessing XML data, with high degree of concurrency, is a necessary condition of the native XML database growth. The aim of this paper is to propose a new concurrency control protocol in XML document access. This protocol is based on primitive operations, which can be treated as a unification platform for any of the XML access methods.

2

On Distributed k-Anonymization

100%

Zhong S.

Fundamenta Informaticae

|

2009

|

tom Vol. 92, nr 4

411-431

EN

When a database owner needs to disclose her data, she can k-anonymize her data to protect the involved individuals’ privacy. However, if the data is distributed between two owners, then it is an open question whether the two owners can jointly k-anonymize the union of their data, such that the information suppressed in one owner's data is not revealed to the other owner. In this paper, we study this problemof distributed k-anonymization. We have two major results: First, it is impossible to design an unconditionally private protocol that implements any normal k-anonymization function, where normal k-anonymization functions are a very broad class of k-anonymization functions. Second, we give an efficent protocol that implements a normal k-anonymization function and show that it is private against polynomial-time adversaries. Our results have many potential applications and can be extended to three or more parties.

3

Hyper-heuristics for power-aware routing protocols

100%

Pilski M. , Seredynski F.

Studia Informatica : systems and information technology

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2008

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tom Vol. 2(11)

37--47

EN

The idea underlying hyper-heuristics is to discover some combination of straightforward heuristics that performs very well across a whole range of problems. In this paper we describe genetic algorithm-based (GA) approach that learns such a heuristic combination for solving energy-efficient routing problem in mobile ad hoc networks (MANETs).

4

Protocols for Wireless Sensor Networks: A Survey

100%

Kochhar A. , Kaur P. , Singh P. , Sharma S.

Journal of Telecommunications and Information Technology

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2018

|

tom nr 1

77--87

EN

This paper presents a survey on the MAC and network layer of Wireless Sensor Networks. Performance requirements of the MAC layer are explored. MAC layer protocols for battery-powered networks and energy harvesting-based networks are discussed and compared. A detailed discussion on design constraints and classification of routing protocols is presented. Several routing protocols are compared in terms of such parameters as: energy consumption, scalability, network lifetime and mobility. Problems that require future research are presented. The cross-layer approach for WSNs is also surveyed.

5

Process algebras for network communication

100%

Gruska D. P. , Maggiolo-Schettini A.

Fundamenta Informaticae

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2001

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tom Vol. 45, nr 4

359-378

EN

Critical issues that arise when process algebras are used for protocol specifications are discussed. To overcome some of these problems, a process algebra for protocol specifications is presented. It is based on Milner's Calculus of Communicating Systems, which is enriched by time and network reasoning. Several bisimulation based semantics for the calculus are defined and their properties are discussed.

6

Stress Testing MQTT Server for Private IOT Networks

88%

Hijazi G. , Habaebi M. H. , Al-Haddad A. , Zyoud A. M. , Hijazi G. , Habaebi M. H. , Al-Haddad A. , Zyoud A. M.

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nr 2

7

Load-balanced route discovery for mobile ad hoc networks

88%

Abolhasan M. , Lipman J. , Wysocki T. A.

Journal of Telecommunications and Information Technology

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2006

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tom nr 1

38-45

EN

This paper presents flow-aware routing protocol (FARP), a new routing strategy designed to improve load balancing and scalability in mobile ad hoc networks. FARP is a hop-by-hop routing protocol, which introduces a flow-aware route discovery strategy to reduce the number of control overheads propagating through the network and distributes the flow of data through least congested nodes to balance the network traffic. FARP was implemented in GloMoSim and compared with AODV. To investigate the load distribution capability of FARP new performance metrics were introduced to measure the data packet flow distribution capability of the each routing protocol. The simulation results obtained illustrate that FARP achieves high levels of throughput, reduces the level of control overheads during route discovery and distributes the network load more evenly between nodes when compared to AODV. This paper also describes a number of alternative strategies and improvements for the FARP.

8

Nowy tester protokołów K1205 - jednoczesna analiza 16 łączy

75%

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

|

1999

|

tom nr 5

324-325

PL

Przedstawiono ogólne zasady konstrukcji, zastosowania i sposób użytkowania nowego testera protokołów transmisyjnych K1205 oferowanego przez firmę Tektronix.

EN

General rules of a construction, applications and usage manner of a new3 protocol tester K1205 offered by Tektronix has been described.

9

A survey of communication protocols in modern embedded condition monitoring systems

75%

Staszewski W. , Jabłoński A. , Dziedziech K.

Diagnostyka

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2018

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tom Vol. 19, No. 2

53--62

EN

The aim of the paper is to present a recent development in the field of communication from the point of view of embedded machine condition monitoring system (CMS). Although the general purpose of CMS remains the same over years, various electronic innovations open new possibilities of enhancement, including lower price, smaller size, larger bandwidth, smaller energy consumption or larger distance for wireless transmission. The paper considers a general notion of an embedded monitoring system, which consists of a sensor, data acquisition and processing unit, storage peripherals, and a communication module for final data destination. For each of these defined parts, a detailed description of possible data transfer protocols and interfaces is given, including popular, and experimental ones.

PL

Celem artykułu jest ilustracja rozwoju technologii komunikacyjnych, z punktu widzenia wbudowanego systemu monitorowania i diagnostyki maszyn (SM&D). Pomimo, iż ogólny cel SM&D pozostaje taki sam od lat, różnorodne innowacje w elektronice otwierają nowe możliwości udoskonalania systemów, m.in. zmniejszanie ceny i rozmiaru, zwiększanie pasma, zmniejszanie zużycia energii, bądź zwiększenie transmisji w systemach bezprzewodowych. Artykuł traktuje system wbudowany jako jednostkę złożoną z sensora, jednostki akwizycji i przetwarzania, miejsca zapisu danych oraz modułu komunikacji. Dla każdego z wymienionych elementów, w artykule przedstawiono szczegółowo możliwe protokoły i interfejsy komunikacyjne, zarówno powszechnie stosowane oraz takie, które są wykorzystywane w systemach prototypowych.

10

IPv6 protocol - characteristics and suggested methods of implementation in existing IPv4 networks using Cisco routers

75%

Kowalik P.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

|

2014

|

tom nr 1

58--61

EN

The article constitutes an introduction to IPv6 protocol and is a review of the existing approaches to ensure the coexistence of IPv6 and IPv4, on the example of homogeneous Cisco network infrastructure. In the first paragraph, the IPv6 protocol has been characterized and compared to the IPv4. Then, concepts connected with IPv6 addressing have been described. As the main part, it has been discussed methods to provide the coexistence of the two IP protocols. It has been characterized the primary option which is the dual stack, two types of both point to point and multipoint tunnels and finally - address translation NAT-PT.

PL

Artykuł stanowi wprowadzenie do protokołu IPv6 oraz jest przeglądem istniejących podejść dla zapewnienia współistnienia IPv6 i IPv4, na przykładzie homogenicznej infrastruktury sieciowej Cisco. W pierwszym rozdziale scharakteryzowano protokół IPv6 i porównano go z IPv4. Następnie opracowano koncepcje związane z adresowaniem IPv6. W głównej części opisano metody do zapewnienia koegzystencji dwóch protokołów IP. Scharakteryzowano podstawową opcję jaką jest podwójny stos, po dwa rodzaje tunelowania punkt-punkt i punkt-wielopunkt oraz w końcu translację adresów NAT-PT.

11

Automating Synthesis of Asynchronous Communication Mechanisms

75%

Gorgônio K. , Xia F. , Yakovlev A.

Fundamenta Informaticae

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2007

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tom Vol. 78, nr 1

75-100

EN

Asynchronous data communication mechanisms (ACMs) have been extensively studied as data connectors between independently timed processes in digital systems. In previous work, systematic ACM synthesis methods have been proposed. In this paper, we advance this work by developing algorithms and software tools which automate most of the ACM synthesis process. Firstly, an interleaving specification is constructed in the form of a state graph, and secondly, a Petri net model of an "ACM-type" is derived using the theory of regions. The method is applied to a number of "standard" writing and reading policies of ACMs with shared memory and unidirectional control variables.

12

The VoIP communication security ptotocols

75%

Zawadzki P.

Studia Informatica

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2008

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tom Vol. 29, nr 4B

27-35

EN

The presently offered VoIP services pose a serious security problem -they are vulnerable to eavesdropping, impersonation, session hijacking and denial of service attacks. The paper presents security analysis of the proposed VoIP protocol stack, including signaling protocol SIP, key management protocols ZRTP and MICKEY and transport layer security protocol SRTP. The VoIP network security subsystem upgrade path is also described.

PL

Powszechnie dostępne usługi VoIP nie zawierają mechanizmów chroniących transmisję, w związku z czym są podatne na podsłuch, przechwytywanie sesji oraz blokadę usługi. W artykule przedstawiono analizę bezpieczeństwa protokołów VoIP z uwzględnieniem protokołu sygnalizacyjnego SIP, protokołów zarządzania kluczami ZRTP i MICKEY oraz protokołu transportowego SRTP. Zaprezentowano również propozycję poprawy proponowanych obecnie sposobów ochrony komunikacji.

13

Zarządzanie mobilnością w nowoczesnych sieciach IP. Część II - Modyfikacje i optymalizacje mechanizmów mobilności

75%

Woźniak J. , Gierłowski K. , Gierszewski T. , Hoeft M.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

|

2013

|

tom nr 1

3-12

PL

Zaprezentowano i poddano analizie rozszerzenia i optymalizacje protokołów mobilności, umożliwiające ich efektywne wykorzystanie w nowoczesnych sieciach IP. Niezależnie od rozwiązań zarządzania mobilnością w warstwie sieciowej, przedstawiono wiele rozwiązań wsparcia mobilności realizowanych w wyższych warstwach modelu ISO-OSI. Dodatkowo przedstawiono rozwój mechanizmów zarządzania mobilnością z wyróżnieniem nowych rozwiązań różnorodnych technik wirtualizacyjnych, w szczególności zmierzających do rozdzielenia identyfikacji adresata od jego lokalizacji w systemie sieciowym oraz do wprowadzenia separacji warstw wyższych od struktury tzw. sieci transportowej. Nakreślono obowiązujące tendencje i kierunki rozwoju protokołów zarządzania mobilnością.

EN

This paper presents optimizations and extensions of the above mobility protocols, allowing them to be successfully deployed in support of modern IP networks and applications. Apart from these classic, network-layer mechanisms, a number of alternative solutions utilizing higher ISO-OSI layer mechanisms have also been described. Moreover, the evolution of mobility support mechanisms is presented, leading to description of new solutions, utilizing abstraction and virtualization techniques to logically separate changing network location information from persistent identity of mobile host or employing completely new approaches, such as universal mobility support lacking necessity to employ well-known mobility agent based solutions.

14

A random access protocol under backoff attack: performance and game-theoretic deterrent

63%

Konorski J.

Systems Science

|

2005

|

tom Vol. 31, no 3

49-57

EN

The IEEE 802.11 medium access control protocol is vulnerable to selfish backoff attacks consisting in the selection of shorter-than-random backoff times by some stations. Administrative punishment and reputation-based prevention of such attacks fail in wireless ad-hoc networks which lack any means of mandating stations' behavior. In this paper, we take an incentive-oriented approach whereby stations are allowed to act so as to maximize their payoffs (obtained bandwidth shares). An approximate Markovian model is proposed to calculate the payoffs under saturation load. The payoff structure specific to CSMA/CA permits to define a two-player game of perfect information, one of the players launching a backoff attack and the other defending itself via a simple jamming mechanism. It is shown that under some conditions, not launching a backoff attack is a weakly best-response strategy against a certain strategy that the defending player may commit herself to.

15

Architektura sieci TCP/IP i jej aplikacje w systemach automatyki i sterowania. Cz 1. Architektura sieci i protokoły

63%

Zankiewicz A.

Elektro Info

|

2010

|

tom nr 7-8

36-41

16

Wykorzystanie protokołu MQTT w systemie sterowania mobilnego robota transportowego

63%

Kazała R.

Logistyka

|

2015

|

tom nr 3

2118--2127, CD 1

PL

Roboty mobilne znajdują coraz szersze zastosowanie w wielu różnych dziedzinach. Obecnie w większości konstrukcji układów sterowania robotów wykorzystuje się zamknięte rozwiązania opracowane przez producentów. Podejście takie powoduje, że trudne jest serwisowanie tych urządzeń oraz integracja z innymi systemami. W rozdziale przedstawiono analizę możliwości wykorzystania otwartych protokołów sieciowych, do wymiany danych w systemie sterowania robotem. Na przykładzie robota mobilnego z manipulatorem pokazano podsystemy występujące w układzie sterowania i określono wymagania dotyczące wymiany danych. Przedstawiono następnie istniejące protokoły sieciowe i przeanalizowano ich funkcjonalność pod kątem zastosowania w układzie sterowania robota. Następnie pokazano przykładową realizację wykorzystującą protokół MQTT.

EN

Mobile robots are increasingly used in many different areas. Currently, most of the design of robot control systems are closed solutions developed by manufacturers. This approach makes it difficult to service these devices and integration with other systems. The paper presents an analysis of the possibilities of using open network protocols for data exchange in robot control system. As example a mobile robot manipulator is shown, its control subsystems and the requirements for data exchange. Next existing network protocols are analyzed in terms of their functionality for using in robot control system. Then there is shown an example of the control system application that uses MQTT protocol.

17

Zintegrowany system kontroli, sterowania i zarządzania procesami energetycznymi w przemyśle, wykorzystujący sterowniki EAZ

63%

Nowakowski A. , Gacek T.

Elektronika : konstrukcje, technologie, zastosowania

|

2005

|

tom Vol. 46, nr 12

8-10

PL

Konieczność posiadania pełnej informacji o poziomie poboru energii elektrycznej, a także zapewnienie ciągłości zasilania wymusza stosowanie specjalistycznych i nowoczesnych systemów, które umożliwią realizację tych wymagań. Omówiono kompleksowy, opracowany w ITR system kontroli, sterowania i zarządzania procesami energetycznymi w przemyśle. System wykorzystuje elementy składowe opracowane w ITR, wychodzi naprzeciw potrzebom pełnej integracji poszczególnych komponentów, realizowanych przez jednego dostawcę sprzętu oraz oprogramowania nadrzędnego.

EN

Complete on-line information on power consumption and uniterrupted power supply are Ndemands which require sophisticated and modern systems to be used in order to satisfy them. In the article there is presented an integrated control and management system for electrical energy processes in industry developed at the Tele- and Radio Research Institute. The system, composed of components elaborated at the Institute, is intended to achieve the Institute's goal of being a supplier of both the protection relays hardware and control and monitoring systems.

18

Bernoulli Meets PBFT: Modeling BFT Protocols in the Presence of Dynamic Failures

63%

Nischwitz M. , Esche M. , Tschorsch F.

Annals of Computer Science and Information Systems

|

2021

|

tom Vol. 25

291--300

EN

The publication of the pivotal state machine replication protocol PBFT laid the foundation for a body of BFT protocols. We introduce a probabilistic model for evaluating BFT protocols in the presence of dynamic link and crash failures. The model is derived from the communication pattern, facilitating an adaptation to other protocols. The state of replicas is captured and used to derive the success probability of the protocol execution. To this end, we examine the influence of link and crash failure rates as well as the number of replicas. A comparison in protocol behavior of PBFT, Zyzzyva and SBFT is performed.

19

Effective Approach for Data Aggregation in Wireless Sensor Network: a Structure Free Approach

63%

Prasad U. , Adane D. S.

Journal of Applied Computer Science Methods

|

2014

|

tom Vol. 6 No. 1

55--65

EN

Wireless Sensor Network consist of thousands sensor node which have limited Power, Computation, Sensing and Communication capabilities. Among all operation of Sensor Node, Wireless Communication consumes most of the energy. So it is necessary to decrease the number of packets transmitted through the network. Many Sensor Node could detect similar event, which increases the overall bandwidth utilization to transmit redundant data. Here Nodes computation is cheaper than communication in terms of energy. So the technique of Data Aggregation is applied to summarize data which decreases the amount of data transmitted in the network, which in turn increases the lifetime of the network. Many Data aggregation protocols are based on a structured approach which is suitable for data collection application. But maintenance of the structure is an extra overhead and this approach is not suitable for dynamic scenario. So we propose an ad-hoc data aggregation protocol for dynamic scenario mainly event based application.

20

Programowanie WWW z wykorzystaniem Delphi

51%

Kaliś A. , Gruber J.

Studia Informatica

|

2003

|

tom Vol. 24, nr 2B

7-14

PL

Najważniejszą cechą programistycznego środowiska Delphi jest jego produktywność, czyli prostota i szybkość tworzenia programów dla platformy Windows oraz Linux. W pracy podjęto próbę przedstawienia możliwości Delphi wspomagających tworzenie aplikacji WWW.

EN

The most important feature of the Delphi environment is it's productivity , which we can understand as easy and rapid application development for Windows and Linux. In this paper there was an attempt of showing the possibilities of Delphi in WWW application development.