Wireless Lan Security Technology Research

With the rapid development of computer network,WLAN is applied to various fields widely for its flexible removing,low price and high transmitting rate.WLAN is a wireless media transmitting with open channel,therefore it has higher security requirement than that with wire.The current WLAN security mechanism design has flaws which seriously hampered the development of WLAN,so it's of significant importance to do research on WLAN security.The security mechanisms of IEEE802.11 serial protocols use a lot of technology on cryptology impertinently,and can't realize the goal of its design at all.The WLAN protocols of national standards of our country,WAPI,have higher securities,but have not got extensive implementation yet at present.The dissertation makes a deep study on security mechanisms of WLAN,and summarizes experiences and lessons in previous protocol design. The dissertation proposed principle of designing security protocol,and proposed an Authentication scheme based on Public Key Infrastructure (PKI).Authentication server authenticates AP;Therefore stations can authenticate AP by using Authentication server. Because there are no shared keys between AP and station,station can but authentiate AP with the help of Authentication server. Authentiation server distributes encrypted temporal key to AP and station,which greatly increases security of temporal key. Propose three key hierarchy,private key,session key,temporal key,and achieve separation of encryption key and Authentication key.Finally, the thesis took the PKI-based authentication scheme for WLAN protocol as an example to demonstrate how to make protocol test.Through the test we verified the completeness and superiority of the improved scheme.