Internet security (Network security) is a big topic that is very important in our society communication system, but it is extremely dynamic and wide in scope. This is the reason that many companies and organizations invest heavily in a dedicated infrastructure security and highly trained specialists.The aim of security monitoring and preventing the network from cyber threats requires vigilance over the network equipment. The case study of this thesis is to provide the possible solution to the problems encountered by the namely network users such as: Internet Game Center (Centrum Halmstad, Sweden) and, the Blueville Internet Cafe (Ede, Nigeria).Our research and information collected over the telephone and a visit at the nearest office. We concluded that both companies mentioned above experienced similar cyber threats. The two companies have internal and external threats such as accessing the network via ssh by using it brute force attack, network war-driver, the installation of spyware, password sniffer, viruses, SQL injection and PHP attacks (web attacks) on the networks. The cyber threats virus and spyware are among the big internet threat to users, organization and companies.We carry out experiments in the lab to tests for threats such as brute force (ssh) attack, password sniffer and war-driver in the Wireless environment. From the results, we are able to the select WPA2 using 802.1x as the best possible way to limit and reduce the strength of cyber-attacks, and as a suggested solution to the namely café problems in our report. We also list different suggestion and solution to the cyber café attacks from our research papers and information gathers from different sources such as library, internet, seminar and textbooks.

This work deals with wireless standard 802.11, primaly about security algorithms used in them. Further there is made analysis of algorithms WEP, WPA and WPA2. This algorithms are described how coding by them works and for easier understandig are added block schemes of their principles. In practical part is realized algorithms WEP, WPA and WPA2 in program Matlab simulink. Model is complemented by graphs which shows how data changes when comming throught this systems.

I en tid då datorer, mobiler och andra enheter som kan ansluta till ett WLAN är stor, kommer säkerheten i dessa WLAN spela en stor roll. Det som skiljer WLAN och LAN när det kommer till säkerheten är att informationen måste färdas trådlöst i luften, vilket kan medföra att obehöriga kan lyssna av eller försöka koppla upp sig mot det trådlösa nätverket. Valet och implementationen av kryptering av WLAN för SME och privatpersoner har en stor inverkan på säkerheten i ens WLAN. Hur enkelt är det för en obehörig person att ta sig in på ett WLAN? Denna undersökning testar WLAN som använder WEP, WPA/WPA2 PSK och WPS med hjälp av en brute force attack för att avgöra om krypteringprotokollen är lämpliga att använda sig av. Testet simuleras med en obehörig laptop som försöker ta sig in in WLAN med brute force på WLAN som använder WEP, WPA/WPA2 PSK och WPS. Program som aircrack-ng och airgeddon används för att utföra testerna.

<p>Syftet med arbetet är att ta reda på hur väl privatpersoner informeras om hur de ska skydda sina trådlösa nätverk och varför. Genom arbetet ska följande frågor besvaras:</p><p>- Vid beställning av bredband inklusive trådlös router från en bredbandsleverantör: informerar leverantören sina kunder om att det trådlösa nätverket bör säkras upp och varför?</p><p>- Blir man informerad om säkerheten när man köper en trådlös router i en lokal affär?</p><p>- Skyddar invånare i Kalmar generellt sett sina trådlösa nätverk?</p><p>Genom användning av kvantitativa metoder i form av observationer har vi svarat på två av frågeställningarna. En kvalitativ metod användes genom att vi skickade enkäter via e-post till fem bredbandsleverantörer.</p><p>Resultaten från vår undersökning visar att majoriteten av invånarna i Kalmar skyddar sina nätverk, men att det är vanligast med en svag kryptering. Undersökningen visar att informationen från lokala affärer och bredbandsleverantörer är bristfällig.</p>

<p>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. </p><p>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. </p><p>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. </p><p>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. </p><p>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.</p>

Syftet med arbetet är att ta reda på hur väl privatpersoner informeras om hur de ska skydda sina trådlösa nätverk och varför. Genom arbetet ska följande frågor besvaras: - Vid beställning av bredband inklusive trådlös router från en bredbandsleverantör: informerar leverantören sina kunder om att det trådlösa nätverket bör säkras upp och varför? - Blir man informerad om säkerheten när man köper en trådlös router i en lokal affär? - Skyddar invånare i Kalmar generellt sett sina trådlösa nätverk? Genom användning av kvantitativa metoder i form av observationer har vi svarat på två av frågeställningarna. En kvalitativ metod användes genom att vi skickade enkäter via e-post till fem bredbandsleverantörer. Resultaten från vår undersökning visar att majoriteten av invånarna i Kalmar skyddar sina nätverk, men att det är vanligast med en svag kryptering. Undersökningen visar att informationen från lokala affärer och bredbandsleverantörer är bristfällig.

This work describes available and used standards, protocols and mechanisms used to secure IEEE 802.11 wireless networks. In the next section are listed vulnerabilities and possible attacks against different types of security. The principles of individual attacks on authentication, WEP security and WPA/WPA2 personal mode are described and realized using various software especially linux program aircrack-ng. Password for WEP security is obtained by passive eavesdropping data, using ARP replay injection and by creating own frames. The last two methods are used to generate traffic on the network, which is captured and then used to derive the WEP password. By injecting ARP frames, password was found in the number 60 000 captured frames and about 180 000 frames of data was needed for passive method. Decryption of WEP frame was done by fragment and KoreK chopchop attacks. This decrypted frame could be used to create fake frames and obtain WEP password. Brute force attack is realized for security WPA (WPA2) personal mode (often due to lack of strong password) by comparing password (passphrase) from password list. Speed of comparing is about 200 passwords/s.

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.

This master´s thesis is about 802.11 standard security techniques and their features. Particular types of this standard and its features are shown in the introduction. Wireless network security cypher alghoritm types, their features, weaknesses and principles of functions are closely described in next few chapters. Realized attacks on these security alghoritms with their principles are described and shown in the practical part of thesis. One chapter is about effectivity, accessibility and practicability valorization of these attacks in practice.

Trådlosa nätverk är av naturen sårbara for avlyssning för att kommunikationen sker med radiovagor. Därfor skyddas trådlosa nätverk med kryptering. WEP var den första krypteringsstandarden som användes av en bredare publik som senare visade sig innehålla flera sårbarheter. Följden blev att krypteringen kunde förbigås på ett par minuter. Därför utvecklades WPA som ett svar till sårbarheterna i WEP. Kort därefter kom WPA2 som är den standard som används i nutid. Den svaghet som kan påvisas med WPA2 finns hos WPA2-PSK när svaga lösenord används. Mjukvaror kan med enkelhet gå igenom stora uppslagsverk för att testa om lösenord går att återställa. Det är en process som tar tid och som därför skyddar nätverken i viss mån. Dock har grafikprocessorer börjat användas i syfte för att återställa lösenord. Grafikkorten är effektivare och återställer svaga lösenord betydligt snabbare än moderkortens processorer. Det öppnar upp for att jämföra lösenord med ännu större uppslagsverk och fler kombinationer. Det är vad denna studie avser att belysa; hur har grafikkortens effektivitet påverkat säkerheten i trådlösa nätverk ur ett verksamhetsperspektiv. / Wireless networks are inherently vulnerable for eavesdropping since they use radio waves to communicate. Wireless networks are therefore protected by encryption. WEP was the first encryption standard that was widely used. Unfortunately WEP proved to have several serious vulnerabilities. WEP could be circumvented within few minutes. Therefore WPA was developed as a response to the weak WEP. Shortly thereafter WPA2 was released and are now being used in present. The only weakness with WPA2 is in the subset WPA2-PSK when weak passwords are being used. Software could easily go through large dictionaries to verify if a password could be recovered. But that is time consuming and therefore providing wireless networks limited protection. However a new area of use with advanced graphic cards has showed that it is providing a faster way of recovering passwords than the ordinary processor on the motherboard. That opens up for the larger use of dictionaries and the processing of words or combinations of words. That is what this study aims to shed light on. How the efficiency of the graphic cards have affected security in wireless networks from a corporate perspective of view.