In this paper I describe my research project in the area of wireless network security. Since in the area of wireless communication, information is propagated through the air instead of through wires, a number of new security risks occur when using the new wireless technologies. Research dealing with these risks and vulnerabilities is, however, rarely seen. Reports about hacker attacks against wireless networks is almost non-existent, but it is only a matter of time before serious attacks will target these systems. Therefore, security aspects of mobile networks 3G and 4G systems and wireless standards like Wireless Application Protocol (WAP), HiperLAN, Bluetooth and wireless LAN standard IEEE 802.11b are central standards of investigation in my research. The main questions, which my research project is concerned with, are whether it is possible to achieve end-to-end security in a wireless network, and, if so, to what costs.