Wireless endpoints in Cisco SD-Access are registered through the fabric wireless integration process, and the fabric WLC is the component that updates endpoint information as clients join the wireless network. The Host Tracking Database stores endpoint identifier and location information used by the SD-Access control plane.
For wired endpoints, the fabric edge detects the endpoint and registers the binding. For wireless endpoints, the fabric WLC is integrated with the fabric and has the client session context, so it provides the endpoint information needed for HTDB updates. Border nodes do not first register ordinary wireless endpoints; their role is to connect the fabric to external networks and other domains. Fabric APs also do not own the complete EID-to-RLOC registration function in the way the controller does. The design implication is that fabric wireless requires correct WLC integration with Cisco Catalyst Center, fabric site configuration, control-plane reachability, and policy integration through Cisco ISE. Client registration, mobility, and policy enforcement depend on this controller-to-fabric relationship being stable. Reference topics: SD-Access wireless, fabric WLC, Host Tracking Database, endpoint registration, LISP control plane.