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Performance Analysis in IP-Based Industrial Communication Networks
Beran, Jan ; Švéda, Miroslav (oponent) ; Hanzálek, Zdeněk (oponent) ; Zezulka, František (vedoucí práce)
With the growing scale of control systems and their distributed nature, communication networks have been gaining importance and new research challenges have been appearing. The major problem, contrary to previously used control systems with dedicated communication circuits, is time-varying delay of control and measurement signals introduced by packet-switched networks, such as Ethernet. The real-time issues in these networks have been tackled by proper adaptations. Nevertheless, market trend analyses foresee also future adoptions of IP-based communication networks in industrial automation for time-critical run-time data exchange. IP-based communication has only a limited support from the existing instrumentation in industrial automation. This challenge has recently been technically tackled within the Virtual Automation Networks (VAN) project by adopting the quality of service (QoS) architecture delivering soft-real-time communication behaviour. This dissertation focuses on the real-time performance aspects from the analytical point of view and provides means for applicability assessment of IP-based communication for future industrial applications. The main objective of this dissertation is establishment of a relevant modelling framework based on network calculus which will assist worst-case performance analysis of temporal behaviour of IP-based communication networks and networking devices intended for future use in industrial automation. Empirical analysis was used to identify dominant factors influencing the temporal performance of networking devices and for model parameter identification. The empirical analysis makes use of the TestQoS tool developed for this purpose. Minor extensions to the network calculus framework were proposed enabling to model the required temporal behaviour of networking devices. Several exemplary models were inferred as a result of classification of different networking device architectures and empirically identified dominant factors. A novel method for parameter identification was used with the modelled devices. Finally, two temporal models of networking devices (a switch and a router) were validated against empirical observations.
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Návrh testů komunikace se skupinovým adresováním v IP
Stehura, Igor ; Matoušek, Petr (oponent) ; Švéda, Miroslav (vedoucí práce)
Táto diplomová práca sa zaoberá multicastom. Vysvetlená je adresácia na úrovni druhej a tretej vrstvy ISO/OSI modelu multicastového adresovania. Pre hžadanie optimálnych ciest multicastových paketov sieťou, routre v sieti používajú multicastové smerovacie protokoly, ktorými sa taktiež práca zaoberá. Sú to protokoly DVMRP, protokol PIM vo svojich dvoch režimoch, PIM Sparse Mode a PIM Dense Mode. Protokol DVMRP využíva k svojmu správnemu fungovaniu protokol IGMP, ktorý je tiež uvedený. V praktickej časti tejto práce sú uvedené zapojenia, na ktorých boli testy vykonané.
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Lawful Interception: Identity Detection
Polčák, Libor ; Baggili, Ibrahim (oponent) ; Hudec,, Ladislav (oponent) ; James, Joshua I. (oponent) ; Švéda, Miroslav (vedoucí práce)
{Internet has became a regular communication channel between law offenders performing malicious activities. Courts or prosecutors authorise lawful interception that targets individual suspects. Lawful interception systems have to identify traffic of the suspects. However, the identifiers that appear in each network packet are short-lived, dynamically assigned, and a single communication session may be split into multiple flows identified by different identifiers. A lawful interception system has to immediately detect that a new identifier covered by an intercept appeared or disappeared. This thesis describes identification in modern computer networks compatible with lawful interception. The focus is on two partial identity detectors: IPv6 address assignment tracking based on monitoring of neighbor discovery and clock-skew-based remote computer identification. Additionally, this thesis proposes identity graphs that link partial identities according to optional constraints that reflect the wording of a warrant. Results of partial identity linking can be utilised by lawful interception systems. The results of this thesis are also applicable in network forensic, and in networks controlled according to user roles.
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Síťová architektura a propojování vestavěných systémů
Trchalík, Roman ; Drábek, Vladimír (oponent) ; Srovnal, Vilém (oponent) ; Švéda, Miroslav (vedoucí práce)
Tato práce se věnuje architektuře vestavěných systémů. Shrnuje současný stav přijatých standardů z rodiny IEEE 1451, které se zabývají vytvářením prostředí pro senzory a jejich zapojení do různých komunikačních sítí. Tyto standardy popisují otevřenou a síťově nezávislou komunikační architekturu pro systém založený na senzorech. Těžištěm práce jsou architektury uvedené jako případové studie, které mohou být využity jako návrhové vzory vestavěných aplikací demonstrované na bezdrátové technologii ZigBee vhodné pro malá zařízení s velmi nízkou spotřebou elektrické energie. Na základě těchto studií jen navržena univerzální brána, která umožňuje aplikační propojení koncových uzlů z různých bezdrátových architektur určených pro senzorové sítě. Práce se dále zabývá modifikováním směrovacího protokolu v síti ZigBee s cílem snížit spotřebu elektrické energie na přenos jednoho datového paketu.
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Připojování vestavěných systémů k intranetu
Damborský, Roman ; Ryšavý, Ondřej (oponent) ; Švéda, Miroslav (vedoucí práce)
Práce zkoumá možnosti připojování vestavěných systémů k intranetu. Bere v úvahu možné technologie a prostředky použitelné k řízení a sběru dat vzdálených senzorů. Zabývá se možnostmi standardu IEEE 1451.1, který definuje abstraktní rozhraní převodníku pro připojování čidel k sítím, aniž by specifikoval konkrétní implementaci komunikace mezi těmito entitami. Dále práce pokrývá návrh a implementaci systému založeného na architektuře popsané standardem IEEE 1451.1.
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Architektury systémů na Internetu se skupinovým adresováním
Veselý, Vladimír ; Matoušek, Petr (oponent) ; Švéda, Miroslav (vedoucí práce)
Spolu s rozvojem šíření multimediálního obsahu a aplikací s distribuovaným výpočtem napříč Internetem vzrostla důležitost optimalizace provozu, zde se jako nejlepší nástroj k dosažení cíle ukázal multicasting. Tato diplomová práce na téma skupinového směrování v Internetu klade důraz zejména na protokoly multicastem užívané, přičemž se snaží shrnuté poznatky aplikovat v konkrétním komerčním řešení a ozkoušet je tak v praxi s výstupem v podobě podrobného rozboru činnosti.
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Network-wide Security Analysis
de Silva, Hidda Marakkala Gayan Ruchika ; Šafařík,, Jiří (oponent) ; Šlapal, Josef (oponent) ; Švéda, Miroslav (vedoucí práce)
The objective of the research is to model and analyze the effects of dynamic routing protocols. The thesis addresses the analysis of service reachability, configurations, routing and security filters on dynamic networks in the event of device or link failures. The research contains two main sections, namely, modeling and analysis. First section consists of modeling of network topology, protocol behaviors, device configurations and filters. In the modeling, graph algorithms, routing redistribution theory, relational algebra and temporal logics were used. For the analysis of reachability, a modified topology table was introduced. This is a unique centralized table for a given network and invariant for network states. For the analysis of configurations, a constraint-based analysis was developed by using XSD Prolog. Routing and redistribution were analyzed by using routing information bases and for analyzing the filtering rules, a SAT-based decision procedure was incorporated. A part of the analysis was integrated to a simulation tool at OMNeT++ environment. There are several innovations introduced in this thesis. Filtering network graph, modified topology table, general state to reduce the state space, modeling devices as filtering nodes and constraint-based analysis are the key innovations. Abstract network graph, forwarding device model and redistribution with routing information are extensions of the existing research. Finally, it can be concluded that this thesis discusses novel approaches, modeling methods and analysis techniques in the area of dynamic networks. Integration of these methods into a simulation tool will be a very demanding product for the network designers and the administrators.
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A NEW DAWN OF NAMING, ADDRESSING AND ROUTING ON THE INTERNET
Veselý, Vladimír ; Muntan,, Jordi Perelló (oponent) ; Grasa, Eduard (oponent) ; Day, John (oponent) ; Švéda, Miroslav (vedoucí práce)
nternet of the year 2015 struggles with problems that are just implications of flawed naming and addressing the concept of TCP/IP, which have an impact on overall routing scalability. Problems such as default-free zone routing table growth, cumbersome multihoming or mobility motivate question whether the Internet deserves major architecture redesign. In the theoretical part, the impact of problems above is evaluated, solutions are discussed and unifying theory compiled and described using formal methods taking into account revered papers about naming, addressing and routing. This work provides in-depth Investigation of two technologies - Locator/Id Separation Protocol a Recursive InterNetwork Architecture. Research contribution is an operational improvement of above-mentioned technologies. New OMNeT++, full-fledged simulation modules compliant with behavior in the specification are used to as verification tool.
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Sector coupling a budoucí podoba sektoru elektroenergetiky a plynárenství
Švéda, Miroslav ; MA, Martin Šik, (oponent) ; Radil, Lukáš (vedoucí práce)
Práce je věnována problematice Sector couplingu. Nejprve je zde řešen vývoj a aktuální stav ve výrobě a spotřebě elektrické energie a také vývoj a aktuální stav těžby a spotřeby zemního plynu v České republice a v Evropské unii. Dále se práce zabývá Sector couplingem, tento pojem je vysvětlen a je zde nastíněno, jakou problematikou se zabývá. Poté jsou popsány jednotlivé technologie, kterými se může v budoucnosti Sector couplingu dosáhnout. V rámci pojednání o těchto technologiích jsou také představeny pilotní projekty těchto technologií. Nakonec je uvedena úvaha o budoucím využití technologií Sector couplingu v České republice.
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Lawful Interception: Identity Detection
Polčák, Libor ; Baggili, Ibrahim (oponent) ; Hudec,, Ladislav (oponent) ; James, Joshua I. (oponent) ; Švéda, Miroslav (vedoucí práce)
{Internet has became a regular communication channel between law offenders performing malicious activities. Courts or prosecutors authorise lawful interception that targets individual suspects. Lawful interception systems have to identify traffic of the suspects. However, the identifiers that appear in each network packet are short-lived, dynamically assigned, and a single communication session may be split into multiple flows identified by different identifiers. A lawful interception system has to immediately detect that a new identifier covered by an intercept appeared or disappeared. This thesis describes identification in modern computer networks compatible with lawful interception. The focus is on two partial identity detectors: IPv6 address assignment tracking based on monitoring of neighbor discovery and clock-skew-based remote computer identification. Additionally, this thesis proposes identity graphs that link partial identities according to optional constraints that reflect the wording of a warrant. Results of partial identity linking can be utilised by lawful interception systems. The results of this thesis are also applicable in network forensic, and in networks controlled according to user roles.
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