IEEE802.11i密钥管理方案的研究与改进

Research and improvement of IEEE802.11i key management program

802.11i的密钥管理方案需要经过四次握手产生PTK,然后经过组播握手产生GTK,加重了STA的计算负担,影响了无线漫游的效率,为此提出一种改进的密钥产生机制。改进后的方案采用EAPOL-Key来传输消息,不修改其帧结构,保持了对原802.11i协议的兼容,同时将四次握手加组密钥握手完成PTK和GTK分发变成只需四次握手就可以同时实现PTK和GTK分发。该方案缩短了密钥分发的过程,减少了分发环节,从而使得漫游环境下的密钥分发效率大大提高,减少了用户接入WLAN的延迟。

Aiming to 802.11 i key management program that can generate PTK and GTK via the way of the four-step handshakes and the multicast handshakes separately, which adds the burden of STA on a large scale and affects the efficiency of the wireless roaming. The key improved-based mechanism is proposed, the improved program uses EAPOL-Key to transmit messages, which not modifying the frame structure, maintaining the 802.11 i protocol compatible. It implements a program that distributed PTK and GTK from four-step handshakes and group-key handshakes reduce to four-step handshakes. Studies show that the program reduced the key distribution process and the distribution chain, so the efficiency of key distribution is greatly improved in roaming environment, and the delay of WLAN user access is reduced.