Using FVRF and IVRF in DMVPN - Cisco Systems

Using FVRF and IVRF in DMVPN
[Dynamic Multipoint VPN (DMVPN)] - Cisco Systems
The advantage of using an FVRF is primarily to carve out a separate routing table from the global routing table (where tunnel interface exists). The advantage of using an IVRF is to define a private space to hold the DMVPN and private network information. Both these configurations provide extra security from anyone trying to attack the router from the Internet by separating out routing information. These VRF configurations can be used on both DMVPN hub and spoke.