Wireless Local Area Networks (WLAN) are beginning to play a much larger role in corporate network environments and are already very popular for home networking applications. This increase in accessibility has created large security holes for hackers and thieves to abuse, that is finally being addressed by stronger security protocols and these security protocols include Wired Equivalent Privacy (WEP), Wi-Fi Protected Access (WPA) and 802.11i (WPA2). In this paper, the authors investigate the performance of Wireless Local Area Networks (WLANs) and security protocols available for WLANs. These existing security protocols have certain vulnerabilities and often hamper network performance as maintain poor trade-off between security and overhead on network performance. Here they propose their security protocol Slot Based Security Scheme (SBSS) in wireless local area network.