Cisco Systems C3850NM410G

The previous controller does not hold any state of the client that has roamed to another controller. In this

case the client traffic is CAPWAP encapsulated by the access point and terminated at the new controller

with which access point has associated.

● L3 roam occurs when the user roams from an access point connected to its controller to a different access

point connected to another controller, where the two controllers are L3 adjacent to each other.

(See Figure 18.)

Figure 18. L3 Roam in Cisco Unified Wireless Network

This is the case when individual controllers are deployed at each distribution block in the campus network, where

the client VLANs are not spanned across. In an existing Cisco Unified Wireless Network, only the PoA moves with

the user mobility, and PoP remains with the initial controller the client first joined. In this case the PoP is also called

the anchor controller, and the PoA is called the foreign controller. The anchor and the foreign controllers hold the

client state since even though the client physically moves to another controller, its traffic is still back-hauled at the

anchor for symmetric routing and policy application.