L3 roaming with concentrator

[iores]

Hi,

I am reffering to the section 9 of this article.

Can someone, please, explain the traffic flow during L3 roaming using a concentrator? How exactly it works? 

If I understood correctly, the default gateways for WLANs in such case are on a core switch as opposed to distributed L3 roaming where default gateways are on distribution switches?

Or the def. gateways remain on distribution switches in both cases but with concentrator traffic gets tunneled to it and then bridged onto the network?

[Ryan_Miles]

L3 Roaming with a MX creates a L2 VPN tunnel from the AP/SSID to the MX. The wireless clients are tunneled to the MX then are placed on a VLAN either local to the MX (if MX is in Routed mode) or bridged onto a L2 VLAN (Concentrator mode) with some external L3 gateway.