Which protocol is used to encrypt and authenticate the data that is sent across a DMVPN tunnel?
- IPsec
- NHRP
- GRE
- mGRE
Explanation: IPsec is the component of DMVPN that provides cryptographic transmission protection for data. While GRE and mGRE provide the tunneling and encapsulation for multiprotocol and multicast traffic, they offer no built-in security; therefore, they must be combined with IPsec to ensure data is encrypted and authenticated.
Related exam: Checkpoint Exam: MPLS and VPN Technologies
