A sequence number based WLAN authentication scheme for reducing the MIC field overhead

Authentication and integrity per frame is an implicit necessity for security in Wireless LANs (Local Area Networks). The existing security frameworks (WPA, 802.11i) provide message integrity code (MIC) for maintaining the integrity and authentication for each data frame. MIC is kept in separate field in the frame and hence adds to the communication overhead. We propose a novel sequence number based scheme to reduce the MIC overhead in the WLANs. The scheme provides per frame message integrity and authentication. It requires only trivial operations like hash evaluation, XOR and addition. It does not require extra bits or extra frame for this purpose and also no change in the existing frame format is required.