This paragraph was taken from the link https://www.cisco.com/c/en/us/support/docs/wireless- mobility/wlan-security/69340-web-auth-config.html#c5: "The next step is to configure the WLC for the Internal web authentication. Internal web authentication is the default web authentication type on WLCs." In step 4 of the link above, we will configure Security as described in this question. Therefore we can deduce this configuration is for Internal web authentication.