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After the client successfully passes the authentication stage, the appliance stores the MAC address of the client in the MAC address filter for the authenticated range. When the client tries to renew its IP address, it receives a new IP address from the authenticated DHCP range.
Note that if the MAC address filter has an expiration period, the member automatically deletes expired MAC addresses from the filter. Therefore, if a DHCP client tries to renew its IP address after the expiration period, the client is redirected to the captive portal because its MAC address is no longer in the MAC address filter. For more information, see Defining MAC Address Filters .
If the user chooses to sign in as a guest, as shown in Figure 32.3, the user can fill in the guest registration page provided by the captive portal.
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