300-730 SVPN: Implementing Secure Solutions with Virtual Private Networks

Route-based IPsec virtual tunnel interfaces create an automatically generated Tunnel<number>-head-0 crypto-map entry and commonly use any-to-any IPsec traffic selectors. FlexVPN is built on this tunnel-interface/VTI model, so both FlexVPN and VTI can produce this form of IPsec SA output. GRE and DMVPN tunnel protection instead identifies GRE traffic with IP protocol 47, whereas a conventional crypto map is typically associated with a physical interface and ACL-selected traffic.