In which VPN type are the Virtual Tunnel interfaces (VTI) used?

Route-based VPN is a VPN type that uses Virtual Tunnel interfaces (VTI) to establish IPSec tunnels between an NSX Edge node and remote sites2. A VTI is a logical interface that is assigned an IP address and is associated with a physical or virtual interface. The VTI acts as an end point of the IPSec tunnel and routes traffic between the NSX Edge node and the remote site2. Route & SSL based VPNs, Policy & Route based VPNs, and SSL-based VPN are not VPN types that use VTI. References: Virtual Private Network (VPN)