Operation Modes
There are two modes of operation for the FlexConnect AP.
Connected mode: The WLC is reachable. In this mode the FlexConnect AP has CAPWAP connectivity with its WLC.
Standalone mode: The WLC is unreachable. The FlexConnect has lost or failed to establish CAPWAP connectivity with its WLC. A WAN-link outage between a branch and its central site is a example of such a mode of operation.
FlexConnect States
A FlexConnect WLAN, depending on its configuration and network connectivity, is classified as being in one of the following defined states.
Authentication-Central/Switch-Central: This state represents a WLAN that uses a centralized authentication method such as 802.1X, VPN, or web. User traffic is sent to the WLC via CAPWAP (Central switching). This state is supported only when FlexConnect is in connected mode.
Authentication Down/Switching Down: Central switched WLANs no longer beacon or respond to probe requests when the FlexConnect AP is in standalone mode. Existing clients are disassociated.
Authentication-Central/Switch-Local: This state represents a WLAN that uses centralized authentication, but user traffic is switched locally. This state is supported only when the FlexConnect AP is in connected mode.
Authentication-Down/Switch-Local: A WLAN that requires central authentication rejects new users. Existing authenticated users continue to be switched locally until session time-out if configured. The WLAN continues to beacon and respond to probes until there are no more existing users associated to the WLAN. This state occurs as a result of the AP going into standalone mode.
Authentication-local/switch-local: This state represents a WLAN that uses open, static WEP, shared, or WPA2 PSK security methods. User traffic is switched locally. These are the only security methods supported locally if a FlexConnect goes into standalone mode. The WLAN continues to beacon and respond to probes. Existing users remain connected and new user associations are accepted. If the AP is in connected mode, authentication information for these security types is forwarded to the WLC.

The Cisco DNA Center open platform for intent-based networking provides 360- degree extensibility across multiple components, including:
+ Intent-based APIs leverage the controller to enable business and IT applications to deliver intent to the network and to reap network analytics and insights for IT and business innovation. These enable APIs that allow Cisco DNA Center to receive input from a variety of sources, both internal to IT and from line-of-business applications, related to application policy, provisioning, software image management, and assurance.
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Reference:
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