Inhalt der Diplomarbeit sind Untersuchungen zur Authentifizierung und Verschlüsselung von drahtlosen Netzwerkverbindungen.

This thesis investigates how Ericsson AB should do to achieve fast and secure handover when roaming in a WLAN. It also provides a security analysis of the system that the wireless access point is part of. The reason for this is that Ericsson is selling an access point called the ABS 2200 aimed at the public hotspot market. The premise was that they wanted a standardized way of handling the roaming issue. At the outset the 802.11F standard looked like a good alternative (in fact the only standardized alternative). Towards last stages of the work though, it was discovered that the 802.11F standard is no longer supported by IEEE. Despite this fact, the conclusion is that secure and fast roaming can be attained if 802.11F is combined with the security standard 802.11i. The security analysis concludes that Denial Of Service is a major threat to WLAN hotspots. It also points out the link between the access point and authentication server is the weakest link in the system. The recommendation is that this link receives an additional layer of protection through IPsec withESP. The algorithm recommendations for ESP are AES for confidentiality and SHA-1 for integrity. This thesis can also be used as a primer on security in WLAN and contains an extensive glossary making it useful as a reference when reading 802.11 standards.

This diploma thesis is focused on implementation of application for security monitoring of network communication of other applications in mobile device with Android platform. Provides users information about security risks that may harm his/her privacy or device. It uses a local VPN to tunnel all data sent to the wireless network. These can be linked to an application that has sent them because the Android kernel is derived from the Linux kernel and can be used to retrieve information about established network connections and the application identifier associated with the connection. This mapping allows to get more information about an app that is potentially dangerous for your mobile device.

This thesis analyzes the wireless network security of the Internet service provider company Net-Connect s.r.o. It identifies its weak points and suggests measures that lead to the increase of the wireless network security.

The healthcare environment is a complex one, saturated by wireless medical devices and sensitive patient data flowing through the network traffic. With the increased popularity of wireless medical devices in the healthcare domain together with the announcement of the new wireless security standard WPA3 comes a need to prepare for a new generation shift in wireless security. The goal of this study is therefore to investigate what challenges the healthcare sector can encounter when faced with the inevitable transition to WPA3. By performing a literature review on the security state of WPA3 compared to its predecessor and performing qualitative interviews with network technicians working in the healthcare sector, three major challenges were identified. IT professionals in the healthcare domain struggle with integrating legacy software systems, keeping middleware software solutions secure, and with handling hardware medical devices that come with outdated wireless standards. By analysing existing literature, several mitigating actions to battle these challenges were presented in this study.

The goal of this thesis is an exploration of the possibilities of Espressif's ESP32 chips in combination with Espressif IoT Development Framework with intention of implementing well-known Wi-Fi attacks on this platform. In this work, multiple implementation proposals were done for deauthentication attack in two variants followed by WPA/WPA2 handshake capture, attack on PMKID, creation of rogue MitM access point, or brute-force attack on WPS PIN, and more. A universal penetration tool ESP32 Wi-Fi Penetration Tool was proposed and implemented, including deauthentication attacks with WPA/WPA2 handshake capture. This tool provides an easy way to configure and run malicious Wi-Fi attacks without any domain knowledge required from the user. The outcome of this work opens new attack vectors for the attacker, thanks to cheap, ultra-low powered, and lightweight ESP32 chips.

The master's thesis deals with the issue of Wireless Local Area Network (WLAN) from the viewpoint of the security and functional principle of security mechanisms. The transition to the issue concerning the security is accompanied by the methods of wireless data transmission operating on the level of physical layer (FHSS, DSSS, OFDM, MIMO), which is followed by the summary of individual 802.11 standards. The next part deals with the issue of shared transmission medium (CSMA/CA), influence of interference and correcting mechanisms (RTS/CTS). Within the security, the principles of the authentication along with the commonly used methods of security (WEP, WPA, WPA2) are described in detail. The first part concerning security deals with the security in the form of the WEP protocol, which is considered insufficient nowadays and points out the imperfect implementation and the consequent risks. The following part describes the security in the form of WPA which eliminates the implementation weaknesses of the previous WEP security protocol. The description of commonly used mechanisms of authentication (PSK, 802.1x), required temporary key management (PTK, GTK), data integrity (MIC) and encryption which uses TKIP protocol are also included. The last part, possible WLAN security, is aimed at the full support of 802.11i standard, which is called WPA2 (sometimes RSN). That part describes the basic encryption security element CCMP, which is based on the AES block cipher modes. The practical part of the thesis deals with the security verification of current wireless networks. In the process of verification the accessible HW means and programming tools of Open Source Software (OSS) are used. By means of verification it has been pointed out that there are possible security risks resulting from the security method which has been used. Also several recommendations how to reduce the security risks of the used method to minimum are mentioned.

Inhalt der Diplomarbeit sind Untersuchungen zur Authentifizierung und Verschlüsselung von drahtlosen Netzwerkverbindungen.

På grund av Covid 19 har de flesta människor valt att jobba hemifrån och de flesta hushåll har en accesspunkt som möjliggör kommunikation mellan flera enheter. Attacker mot Wi-Fi accesspunkter har ökat under de senaste åren på grund av sårbarheter som kan finnas i accesspunkten. När en sårbar väg hittas i accesspunkt kan detta ledda till att angriparen använder den sårbara vägen för att göra ett intrång och skada en eller flera enheter i hemnätverket och även företagens enheter. Teknikens framsteg har hjälpt oss att implementera flera säkerhetsåtgärder som kan skydda accesspunkten vid intrångsförsök. Syftet med detta arbete är att lägga fokus på att ge rätt kunskap för nya nätverkstekniker för att öka medvetenhet inom säkerheten i hemnätverk. Målet med detta examensarbete är att ge en djupare kunskap för nya nätverkstekniker för att kunna förhindra eller minimera attacker som orsakas av sårbarheter i ett hemnätverk med Wi-Fi accesspunkt och ta fram en rutin för hur det ska skyddas. Efter vi har identifierat en mängd attacker och själva utfört dem, visade resultatet att det var lätt att manipulera en sårbar accesspunkt med de valda attacksverktygen i detta arbete och experimenten har påvisat oss vikten av att implementera rätt säkerhetsåtgärder och hur väl de skyddar accesspunkten mot ett intrångsförsök. / Due to Covid 19, most people have chosen to work from home and most households have an access point that enables communication between several devices. Attacks against Wi-Fi access points have increased in recent years due to vulnerabilities that may exist in the access point. When a vulnerable path is found in the access point, this can lead to the attacker using the vulnerable path to breach and damage one or more devices in the home network and even corporate devices. Advances in technology have helped us implement several security measures that can protect the access point in case of intrusion attempts. The purpose of this work is to focus on providing the right knowledge for new network technicians to increase awareness in home network security. The goal of this thesis is to provide a deeper knowledge for new network technicians to be able to prevent or minimize attacks caused by vulnerabilities in a home network with a Wi-Fi access point and develop a routine for how to protect it. After we have identified several attacks and performed it ourselves, the result showed that it was easy to manipulate a vulnerable access point with the selected attack tools in this work and the experiments have shown us the importance of implementing the right security measures and how well they protect the access point against an intrusion attempt.

This diploma thesis deals with wireless computer networks in a point of view security. It contains security principles and standards used in these networks. It shows failings of old security methods in contras of new standards. The result of the thesis is a design of the metropolitan network and its realization. In this network appropriate solutions of security are used. The last part of the thesis deals with a design of web applications created in the PHP programming language and SQL database system.