Nowadays, wireless computer networks catch the attention of many customers with their advantages. They are mobile, easy to install and easy to expand. Wireless computer networks technology finds many new applications as data transfer capabilities improve and cooperation among the hardware/software producers, via standardization, increases. Also, depending on the hardware price drops, the number of users increases rapidly. Wireless local area computer networks can run on various standards, but only one of them is used widely which is the main reason of these networks' popularity today. This wireless local area network standard is IEEE 802.1 1 standard. In addition to their various advantages, wireless computer networks are expected to provide with data security. The medium for data transfer in these networks is the air, which gives access to any data to anyone. This eases data sniffing. To provide security, IEEE 802.11-1999 standard requires two ways authentication and data encapsulation. However, in year 2000, some published studies pointed out that IEEE 802.1 1-1999 standard is far away from providing any security as it have claimed. To fix the security holes and related security problems, IEEE established 802.11i research group and after four years of research, in 2004, this group announced IEEE 80 l.lli-2004 standard. This thesis studies the security protocol in IEEE 802.11-1999 standard and investigates the related problems along with the new security protocol and its measure in the new 802. 1 li standard. Also, a simulation program is written for the 802.11 networks. In this program, 802.1 1 wireless networks are simulated on a computer environment and the stages of a user communication over the network are shown. This simulation program mimics and runs all the new security measures announced in 802.11i standard including the new data encapsulation mechanism. The security architecture and other mechanisms of new 802.11i standard are investigated individually in this thesis. Thus, this thesis sequentially analyses each step of the new standard and explores the security shortcomings. |