Which interface type must be used in an IKEv2 deployment that needs to route non-IP traffic?
Correct Answer: C
In an IKEv2 VPN deployment, if there is a requirement to route non-IP traffic (such as IPX, AppleTalk, or other Layer 3 protocols besides IP), a GRE (Generic Routing Encapsulation) interface must be used.
IKEv2 natively supports only IP traffic when using traditional Virtual Tunnel Interfaces (VTI) or Dynamic Virtual Tunnel Interfaces (DVTI).
However, GRE encapsulates non-IP protocols within an IP packet, allowing these protocols to be transmitted over an IPsec-protected GRE tunnel.
A typical GRE over IPsec configuration looks like this:
interface Tunnel0
tunnel source GigabitEthernet0/1
tunnel destination <remote_peer_IP>
tunnel mode gre ip
ip address 192.168.1.1 255.255.255.252
Then, IPsec is applied to protect the GRE tunnel.