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Wireless sensoric network for hop drying facility
Čapek, Lukáš ; Čech, Jakub (referee) ; Šnajdr, Václav (advisor)
The purpose of this project is to build a wireless sensor network for measuring temperature and relative humidity in hop drying facility. This is a monitoring device, consists of several sensor units and one control and display unit. Display unit coordinates a whole network and can display data on LCD or download collected data to PC. Sensor unit measures a relative humidity, temperature, battery voltage and transmits data to display unit. Units contain a transceiver which operates in ISM band 868 MHz. Circuits are driven by 8-bits microcontroller Freescale.
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Location visualization of sensor units
Hulanský, Jozef ; Verner, Lukáš (referee) ; Komosný, Dan (advisor)
This master thesis deals with wireless sensor network with protocol IPv6. In the begining there are explained the priciples of communication in wireless sensor network, and based on this teories are configured a wireles network with predefined development kit. Furthermore, by using geographic coordinates, positions of the nodes are displayed on a website, what is a part of this thesis. On this website are also presented the measured values from sensors. For saving all informations and measured values about each nodes was used remote MySQL server. Communication between this server and 6LoWPAN network provide Perl script which is runs at periodical intervals. With this method automatization of the whole system are ensured.
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Security Protection efficiency improvement for Wireless Networks
Marušek, Michal ; Burda, Karel (referee) ; Škorpil, Vladislav (advisor)
Nowadays every wireless radio-communication services encompass huge type of technology used for transfer video, voice or data. Wireless communication is the most expanded branch and many companies are using this technology because of low cost and simply management. The biggest advantage is easy connection to shared wireless medium and allows users of network to move around whole covered area. The most expanded types of wireless networks are called Wireless LAN (WLAN). With rising number of WLANs is rising chance to attack shared wireless medium by hacker and many sensitive information can be stolen or modified. To avoid this chance was created the first security protocol used in WLAN called WEP. Its goal was protect data transmitted trough WLAN as strong as were protected in wired networks. Unfortunately WEP was hiding a big weakness which can be used in a crack of WLAN in a minute with the aid of special software. Example of this kid of software can be Airsnort constructed to monitor shared medium and captured every packet transferred trough this medium. Based on statistical method Airsnort can obtain hidden password in a few minutes. The second type of this software can be Aircrack-ng, which can crack hidden password without any user connected to WLAN. Aircrack-ng uses active techniques to generate network load and can obtain password more effectively and faster. The result of both cases was successful and protection of WLAN was completely cracked. Later was created new security protocol called WPA, which had to fix the cryptography weakness of previous WEP. WPA was only temporary security protocol, during standard 802.11 was developing which had to offer highest security and integrity protection of transferred data trough WLAN. For this reasons was created new version of WPA called WPA2 which satisfy requirements of standard 802.11i. Both protocols WPA/WPA2 contain weakness, which can crash security of WLAN. This crack is based on authentication PSK. Attacker during authentication is using information from four-way handshake between user of WLAN and access point. Based on this information attacker can crack password with the aid of password list attack which took approximately 30 minutes. Based on previous result is important to chose strong password contains alphanumeric string or special strings with satisfy length.
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Modelling the wireless transmission channel in OPNET Modeler simulation environment
Spiglazova, Světlana ; Koutný, Martin (referee) ; Hošek, Jiří (advisor)
This diploma thesis deals with modeling wireless transmission in simulation environment OPNET Modeler. In theoretical part, there is described the very substance of spreading the signal via electromagnetic wave including impact of the surroundings that affects the spreading. These impacts have an influence on described selected parameters of wireless transmission of the signal characterizing its quality. Furthermore, there is described the OPNET Modeler setting, which allows designing the wireless transmission and by means of simulation verifies its functionality and acquires it is parameters. The transmission of the signal from transmitter to receiver itself is divided to individual steps, which are described in detail considering the implementation in aforementioned environment. In practical part, there is configured the basic model of wireless network and also executed series of simulations with different variants of commonly adjustable basic parameters of the transmission, as signal modulation, antenna types and network topology. Additionally, attention is turned to the stages of transmission itself, philosophy of their cooperation based on sharing the information via data units called TDA and their implementation in source code of the C++ language called transmission models. Based on these foundations is beyond beforehand defined created new user TDA and by means of simulation verified its correct implementation within packet switching. Values of the selected including user TDA are written in the window of simulation console with the help of the C++ language. Acquired results of the simulations are analyzed and documented in the conclusion. Source codes are available in the diploma thesis appendix.
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Desing of New Network Infrastructure for Youth Home
Pexa, Marek ; Jordán, Vilém (referee) ; Ondrák, Viktor (advisor)
This bachelor thesis is focused on design network infrastrcture and telecommunication outlets in the fourth floor for needs of Domov mládeže. This work is based on analasys which was accomplished from requirements of the investor. This bachelor thesis contains teoretical resources which help better understand the issues of this topic. The aim of this bachelor thesis is to design active and pasive elements of network and economical assesment.
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Attacks on Standard 802.11
Burian, Vojtěch ; Horváth, Tomáš (referee) ; Novotný, Bohumil (advisor)
Thesis is concerned about standard 802.11 especially wireless network security in historical and in current way. First part is focused on WEP secured wireless network problematics. Consequently, in different point of view we are focused on network security which was developed recently, for example WPA and WPA2 security. It will be marked the basic functioning and brief overview of standard 802.11, introduction to the known attacks on wireless network security and also indicate the main mistakes. Many older devices have only WEP security. Therefore, in this thesis is designed better and more coherent system of security of the WEP protocol. As well modern methods of security WPA and WPA2 are included. Second part is focused on the simulation of attack on security networks. In this part the problematic with beaking security WEP, WPA and WPA2 is discussed.
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Wireless Network Aspects
Pluhař, Ondřej ; Ponížil, Michal (referee) ; Koch, Miloš (advisor)
The bachelor’s thesis is about wireless communication, concretely wireless fidelity networks. It deals about IEEE 802.11 standard and also about its modulations. History, development, kinds and properties of wireless network and security is also mentioned. Current situation of one particular company is viewed in further part of the thesis. Some innovations in internet access and security of wireless communication in company network is suggested.
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Wireless Fidelity Networks
Gurka, David ; Boráň, Tomáš (referee) ; Koch, Miloš (advisor)
In the bachelor’s thesis I solve the problems of wireless networks. This theme includes all information about the main terms in wireless networks, amplification of questions about network security and proposal of solution with complications in creation of this network. I will take a look on usage of wireless technology in a company network, to see possible risk origins. I will try to propose and choose optimal usage policy of wireless network.
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Wireless Sensor Network Base on Android Platform
Bělohoubek, Tomáš ; Zbořil, František (referee) ; Samek, Jan (advisor)
Mobile devices on Android platform includes many sensors, wireless modules and methods for determining the position. This makes them interesting for use in area of sensor networks. This thesis examines the potential of these devices and their practical use in wireless sensor networks. Design and implementation of the custom application is based on these findings.
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Analysis of Quality of Service Assurance in Wireless Networks
Hornyak, Tomáš ; Kouřil, Jiří (referee) ; Hošek, Jiří (advisor)
This Bachelor thesis deals especially with possibilities of quality of service assurance and mobility implementation in wireless networks. It deals primarily with the possibilities of the IEEE 802.11e standard, with the applicability of the Mobile IPv4 protocol and with the computer simulation of their mutual coactions in the OPNET Modeler 12.0 environment. In the first part of the thesis the standard IEEE 802.11e is first of all analysed from the theoretical point of view. It is followed by the detailed description of the IEEE 802.11e standard, its individual parts and implementation possibilities of advanced technologies of the access to the medium which are included in the standard. In this part even the individual advantages and disadvantages of the original access methods of wireless networks of IEEE 802.11 standards are briefly outlined. Further part of this work deals with the theoretical analysis of mobility service assurance in the IP networks and with the mobility implementation in individual layers of the ISO/OSI models. Then the Mobile IPv4 protocol is presented here that carries out the mobility in the IP networks. The principle of this protocol is mentioned here and its individual components and the network architecture are presented. In the next part, on the basis of theoretical pieces of knowledge in the environment of the OPNET Modeler simulation tool the effect of the standard IEEE 802.11e implementation is examined on the selected statistics of the wireless local network. Furthermore the effect of the load in the network is followed up and standard modifications are discussed here to reach optimum results. The last part deals with the computer simulation of the Mobile IPv4 protocol in the wireless networks. Then the support of the IEEE 802.11e standard is implemented into the functioning network model and the reciprocal coactions of both technologies and a possible appearance of any problems are examined. For comparison, it is here in the OPNET Modeler environment even the mobility simulated which is based solely on the link layer.
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