Research And Improvement Of Wlan Safety Standard

The security requirements for a WLAN include data confidentiality. IEEE 802.11i is designed to provide an enhanced security mechanism in the Medium Access Control(MAC) layer for 802.11 network,The802.lli specification defines the Robust Security Network Association (RSNA). RSNA Provides two data confidentiaiity protocols , called theTemporaI Key Integrity Protocol(TKlP) and the Counter-mode/CBC-MAC Protocol(CCMP),and the RSNA establishment procedure,includilg 802.1x authentication and key management protocols.The article analyzes the whole sceuirty protocol in the802.lli specification,considering data cofidentiality,integrity,mutual authentication,and availability.After researching,we find that 802.lli can provide an effective data confidentiality and integrity when CCMP is used in addition,an authenticatlon process,combining the 802.1x authentication and key manasement procedures is performed to mutrally authenticate the devices and generate a fresh session key for data transmissions. Therefor , an implementation of 802.11i protocols in a WLAN enhanced the security in the Wlans.Unfortunately,as the 802.11i does not emphasize the building efficiency when the protocol fails,there are several DoS attacks. The article reviews the known DoS attacks on unprotected management frames and EAP frames,and discusses the method to reduce the attacks in 802lli. Two new DoS attacks and possible repairs are identified:the vulneratrility in RSN IE and 4-Way Handshake. As the former, three methods are proposed: management frame confirming; authenticating RSN IE early; authenticating RSN IE unstrictly.The last one is better.As the latter, two methods are suggested:TPTK and msg1 authentication.The second method is the most safe, if AS is not attacked.Finally some tradeoffs in failure-recovery strategies are discussed and an improved scheme of 802.lli is proposed to address all the discussed vulnerabilities. As different failure stages,we can chose different recovery point, so the probability attacked will be cut down at most extent.