300-440 Question 176
Select 3An enterprise network engineer is tasked with deploying a point-to-multipoint VPN solution using GRE tunnels. The engineer decides to implement mGRE (Multipoint GRE). Which of the following statements are correct regarding mGRE and its configuration?
- A
mGRE eliminates the need for manually defining tunnel destination addresses in point-to-multipoint environments.
- B
mGRE tunnels require a unique tunnel interface for each remote site.
- C
Dynamic routing protocols such as EIGRP or OSPF can be used over mGRE tunnels to exchange routes.
- D
mGRE relies on NHRP (Next Hop Resolution Protocol) for resolving remote tunnel endpoints in point-to-multipoint configurations.
- E
mGRE inherently provides encryption for data traffic over the tunnel.
Show answer and explanation
Correct answers: A, C, D
Explanation
mGRE is a scalable solution for point-to-multipoint VPNs, eliminating the need to define static tunnel destinations for each remote site. It integrates with dynamic routing protocols and relies on NHRP for resolving remote endpoints. However, mGRE does not provide encryption by itself, so additional configurations like IPsec are required for secure data transmission.
- A. Correct.
Correct. One of the key advantages of mGRE is that it supports multipoint configurations, which eliminates the need to manually define tunnel destinations for each remote site.
- B. Incorrect.
Incorrect. Unlike traditional GRE, mGRE allows a single tunnel interface to support multiple remote sites, making it more scalable.
- C. Correct.
Correct. mGRE supports dynamic routing protocols like EIGRP or OSPF, which are often used to simplify routing and provide failover capabilities in point-to-multipoint environments.
- D. Correct.
Correct. mGRE relies on NHRP to dynamically resolve the IP addresses of remote tunnel endpoints, enabling scalable point-to-multipoint configurations.
- E. Incorrect.
Incorrect. mGRE itself does not provide encryption. For secure communication, additional configurations such as using IPsec with mGRE are required.