300-320 Question #87: Real Exam Question with Answer & Explanation

The correct answer is A: GRE. Basic IPsec VPNs encrypt traffic between endpoints but do not natively support dynamic routing protocols because they lack a routable interface. GRE (Generic Routing Encapsulation) creates a logical tunnel interface over which routing protocols like OSPF or EIGRP can run, and is

Question

Which two VPN solutions extend the routing capabilities of basic IPsec VPNs? (Choose two.)

Options

AGRE
BNVI
CDES
DVTI
EAES

Explanation

Basic IPsec VPNs encrypt traffic between endpoints but do not natively support dynamic routing protocols because they lack a routable interface. GRE (Generic Routing Encapsulation) creates a logical tunnel interface over which routing protocols like OSPF or EIGRP can run, and is commonly combined with IPsec for security. VTI (Virtual Tunnel Interface) provides a routable, point-to-point interface for IPsec, enabling dynamic routing without the overhead of GRE. DES and AES are encryption algorithms, not VPN architectures, and NVI (NAT Virtual Interface) is related to NAT, not routing extension.

Community Discussion

No community discussion yet for this question.

Full 300-320 Practice