One of the major problems of modern Internet is the upcoming depletion of addressing space in IPv4 protocol. This master thesis focuses on the study of network protocol IPv6, the possibilities of expanding this protocol in the Internet using the appropriate tunelling method and ways of tunnel management, especially the TIC protocol. Major goal of this work is using knowledge of protocols in a design and implementation of the server part of tunnel broker system, which uses mentioned tunneling method and is compatible with the open source client AICCU. Second part of this work deals with testing and pilot deployment of this system. Main benefit consists in creation an open source tunel broker system. Real deployment of this system is particularly advantage for Czech users as a low latency tunnel IPv6 Internet.

Modern heterogeneous networks present a great challenge for network operators and engineers from a management and configuration perspective. The Tail-f Systems’ Network Control System (NCS) is a network management framework that addresses these challenges. NCS offers centralized network configuration management functionality, along with providing options for extending the framework with additional features. The devices managed by NCS are stored in its Configuration Database (CDB). However, currently there is no mechanism for automatically adding network devices to the configuration of NCS, thus each device’s management parameters have to be entered manually. The goal of this master’s thesis project is to develop a software module for NCS that simplifies the process of initial NCS configuration by allowing NCS to automatically add network devices to the NCS CDB. Apart from developing the software module for discovery, this project aims to summarize existing methods and to develop new methods for automated discovery of network devices with the main focus on differentiating between different types of devices. A credential-based device discovery method was developed and utilized to make advantage of known credentials to access devices, which allows for more precise discovery compared to some other existing methods. The selected methods were implemented as a component of NCS to provide device discovery functionality. Another focus of this master’s thesis project was the development of an approach to network topology discovery and its representation. The aim is to provide both a logical Internet Protocol (IP) network topology and a physical topology of device interconnections. The result is that we are able to automatically discover and store the topology representation as a data structure, and subsequently generate a visualization of the network topology. / Moderna heterogena nätverk utgör en stor utmaning för operatörer och ingenjörer att hantera och konfigurera. Tail-f Systems NCS produkt är ett ramverk för nätverks konfiguration som addresserar dessa utmaningar. NCS är ett centraliserat nätverks konfigurations verktyg. NCS är användbart som det är, men kan också byggas ut av användaren med ytterligare funktioner. De enheter som hanteras med NCS lagras i konfigurationsdatabasen (CDB). För närvarande finns det ingen automatiserad mekanism för att addera nätverksenheter till NCS, och varje enhets parametrar måste fyllas i manuellt. Detta examensarbetes mål är att utveckla en mjukvarumodul för NCS som förenklar NCS konfiguration genom att automatiskt lägga nätverksenheter till NCS CDB. Förutom att utveckla programvara för enhetsidentifiering, syftar detta projekt till att sammanfatta befintliga metoder och utveckla nya metoder för automatiserad nätverksenhetsidentifiering med huvudfokus på att skilja mellan olika typer av enheter. En metod baserad på förkonfigurerade autenticeringsuppgifter har utvecklats och den används för att precist kunna identifiera olika typer av nätverkselement. De valda metoderna har implementerats som en optionell modul till NCS som erbjuder enhetsidentifieringsfunktionalitet. Ytterligare ett fokus för detta examensarbete har varit att utveckla metoder för identifieraing av nätverkstopologin, och modeller för hur topologin ska representeras.  Vi har syftat till att identifiera både den logiska IP nätverkstopologin (L3) och den fysiska topologin av sammankopplade enheter (L2). Den viktigaste uppgiften har varit att identifiera och lagra topologi representation som en datastruktur, och dessutom generera en visualisering av nätverkstopologin.

Master's thesis analyzes available network device configuration options and describes NETCONF configuration protocol and NETCONF event notifications extension in details. It describes Netopeer, open configuration platform developed on Liberouter project, and its pitote deployment as FlowMon probe remote configuration system. Newly designed Netopeer architecture, which adds support for NETCONF event notifications, was verified by reference implementation. Security of the new design and implementation was analyzed, and recommended system settings were provided. This Master's thesis is based on results of previous bachelor's thesis of author and on existing software tools developed by the Liberouter project.

his semestral´s thesis deals with proposal and system implementation for automatic configuration of Cisco network devices. This system is called AutoConf and it is intended for distant copying configuration files from eagle-server to the switches and routers in Cisco academy laboratory. It is handled by web pages placed on eagle-server. In this system, user can create new laboratory exercises with configuration files for network devices and then these files could be used for configurations. Informations about done configurations are saved in relation database MySQL. Network devices which will be configured by system AutoConf have to be connected with eagle-server. To setup their connection settings was created decision-making mechanism. If it detects physical connection between network device and eagle-server before network device starts, it will set network device for communication with eagle-server.

This masters thesis describes simulation of network using Network Simulator. Model of network and description of simulation is extracted from the analysis of configuration files of active network devices, and translated by a parser. Concept and implementation of the parser is described here. Because IPv4 addressing is not supported in Network Simulator, it was added as a new module. The Network Simulator is also extended by filtering properties of packets using access control lists. Practical usage of the implemented modules is demonstrated on a simulation of real network.

Táto práca sa zaoberá problematikou identifikácie sieťových zariadení na základe ich chovania v sieti. S neustále sa zvyšujúcim počtom zariadení na sieti je neustále dôležitejšia schopnosť identifikovať zariadenia z bezpečnostných dôvodov. Táto práca ďalej pojednáva o základoch počítačových sietí a metódach, ktoré boli využívané v minulosti na identifikáciu sieťových zariadení. Následne sú popísané algoritmy využívané v strojovom učení a taktiež sú popísané ich výhody i nevýhody. Nakoniec, táto práca otestuje dva tradičné algorithmy strojového učenia a navrhuje dva nové prístupy na identifikáciu sieťových zariadení. Výsledný navrhovaný algoritmus v tejto práci dosahuje 89% presnosť identifikácii sieťových zariadení na reálnej dátovej sade s viac ako 10000 zariadeniami.

Embedded devices such as routers, switches, and firewalls commonly have sensitive information stored on them such as passwords, cryptographic keys, and information about the network around them and services that these device(s) provide. When disposing of or reselling this equipment in the secondary market it is crucial to erase this sensitive information. However, there is an important question that must be asked: Do the erase commands and routines offered by the device manufacturers actually erase the sensitive data? This thesis investigates methods and tools to determine the completeness of this erasure in some common network devices. These methods are used on a sample of networking equipment found to still contain sensitive information after being erased according to vendor recommendations. A computer program was developed to show how this information can be removed. The information in this document is useful for equipment owners, brokers and others looking to remarket their current equipment; all of whom want to minimize the risk of leaking sensitive data to other parties. / Nätverksutrustning såsom routrar, switchar och brandväggar har ofta känslig information lagrad internt, som lösenord, kryptografiska nycklar, information om nätverket runt dem samt tjänster de tillhandahåller. Om denna utrustning ska säljas på andrahandsmarkanden eller på annat sätt byta ägare är det viktigt att all känslig information raderas.  Men kan man lita på att raderings rutiner och metoder som tillhandahålls av tillverkaren verkligen raderar känslig data? Denna avhandling undersöker lämpliga verktyg och metoder för att granska vilken information som minnen i inbyggda system innehåller. Dessa metoder testas praktiskt på några system som visar sig ha kvar känslig information efter att de raderats enligt tillverkarens rekommendationer. Ett datorprogram som demonstrerar hur denna information kan undersökas och raderas finns med som en del av avhandlingen. Informationen i detta dokument är användbar för ägare av datakomutrustning, mäklare av sådana samt andra som vill minimera risken för att läcka känslig information vid återförsäljning av sin begagnade utrustning.