Wireless Network Security Mechanisms

Wireless LAN has some advantages as follows: its agility and convenience to organize the network, fast to access, costs low on maintenance. There's a huge market in front of its application because of such advantages. But companied with the fast development of the WLAN technology, people become more and more concerned about its security issue. So, at the year of 1997, the IEEE established the 802.11 standard for WLAN, and such standard uses the mechanism of WEP(Wired Equivalent privacy), which based on the algorithm of RC4, to improve its security. However, several kinds of security leaks have been discovered in the WEP during some later work of analysis and research. It just failed to guarantee the data's confidentiality and integrity; neither can it do the identity authentication to the accessed users.This paper has done research on those two aspects of the safe leakages and digital encryption techniques of WEP, which is based on the analysis of security mechanism in existence. Firstly, it introduces an authentication technology of digital certificate based on the authenticated structure of 802.1x. This method can solve the problems of the hidden trouble of secret key share and AP's bidirectional authenticated trouble. Secondly, it introduces AES algorithm and uses it on the updating secret key, it also can solve IV's excessively short problem effectively and the trouble of secret key repetition. So, the encrypted intensity has been promoted a lot. On the aspect of digital integrity verify, it introduces the Michael algorithm, solving the problem that in WEP mechanism, CRC can not guarantee the verity of information integrity. In the end, making the secrecy transfers to documents become true.In this paper, the encrypted intensity and digital verify capacity of secrecy transfers system has promoted a lot compared to WEP. Comparing to TKIP, the speed is faster and also the agility is better. The AES secret key updating module can be used to make a DSP chip in some day, because the 802.11 TGi team prescribed that the products of 802.11RSN could support AES algorithm. So, the computing speed of digital encrypted module has been greatly promoted, and also promoted the document transfer speed.