Captive Portal and the other standard user mapping methods might not work for certain types of user access. For example, the standard methods cannot add mappings of users connecting from a third-party VPN solution or users connecting to a 802.1x-enabled wireless network. For such cases, you can use the PAN-OS XML API to capture login events and send them to the PAN-OS integrated User-ID agent. See Send User Mappings to User-ID Using the XML API for details.