FlexConnect, previously known as Hybrid Remote Edge Access Point (HREAP) mode, is supported with central authentication configuration deployment starting from WLC 7.2.110.0. For additional details regarding FlexConnect support, refer to the release notes for the applicable wireless controller platform.
http://www.cisco.com/c/en/us/td/docs/security/ise/1-2/compatibility/ise_sdt.html#79546
Cisco ISE Central Web Authentication (CWA)
Customers may choose to use Cisco ISE as their guest management solution. Using Mac Based Authentication (MBA) on a open network, Cisco ISE can instruct the AP to redirect the client to the guest portal hosted on the Cisco ISE server. After the client satisfies the guest portal requirements, Cisco ISE will instruct the AP using CoA to grant elevated network access.
https://documentation.meraki.com/MR/Encryption_and_Authentication/Change_of_Authorization_with_RADIUS_(CoA)
Regards
Gagan
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