As shown in Figure 1, there are three shared key authentication techniques available:

WEP is no longer recommended. Its shared WEP keys have proven to be flawed and; therefore, should never be used. To counteract shared WEP key weakness, the very first approach by companies was to try techniques, such as cloaking SSIDs and filtering MAC addresses. These techniques have also proven to be too weak.

Following the weakness of WEP-based security, there was a period of interim security measures. Vendors like Cisco, wanting to meet the demand for better security, developed their own systems while simultaneously helping to evolve the 802.11i standard. On the way to 802.11i, the TKIP encryption algorithm was created, which was linked to the Wi-Fi Alliance WPA security method.

Modern wireless networks should always use the 802.11i/WPA2 standard. WPA2 is the Wi-Fi version of 802.11i and; therefore, the terms WPA2 and 802.11i are often used interchangeably.

Since 2006, any device that bears the Wi-Fi Certified logo is WPA2 certified.

Note: Wireless-N networks should use the WPA2-Personal security mode for best performance.

The table in Figure 2 summarizes the three types of shared key authentication methods.