DMVPN combines hub-and-spoke simplicity with full mesh efficiency. Spokes initially connect only to the hub. When spoke A needs to reach spoke B, the hub helps them create a direct tunnel dynamically.
DMVPN uses NHRP (Next Hop Resolution Protocol) to discover spoke addresses. After the initial hub-assisted introduction, spokes communicate directly. When the direct conversation ends, the spoke-to-spoke tunnel closes. You get on-demand full mesh without preconfiguring every possible tunnel.