Abstract: The WAPI certificate authentication protocol implements the peer mutual authentication between AE and ASUE and guarantees the access of the legislate users, to the legislate network. But because in general the public key computation is complex, this introduces an access bottle-neck for the network. The trusted third party is made full use of and the counts of public key computation in AE and ASUE are reduced when they operate in frequent handover environment or their power is limited in some applications, so an improved protocol is presented. PCL-based analysis and test result show that the new protocol has the same security features as that original one and its efficiency and system acceptance are obviously improved.

Key words: WLAN, WAPI, security protocol, performance analysis