ANS-C01 Question 171
Select 2Your organization has a hybrid cloud architecture where the on-premises network and the AWS VPC use overlapping CIDR ranges (192.168.0.0/16). You need to establish secure communication between the two environments using AWS VPN while avoiding IP conflicts. Which of the following solutions can address this issue?
- A
Use AWS Transit Gateway with VPN and employ route propagation to manage overlapping IP ranges.
- B
Configure Network Address Translation (NAT) Gateway in the VPC to translate the overlapping IP ranges into non-overlapping ranges.
- C
Use AWS Transit Gateway's Transit Gateway Network Manager to automatically resolve overlapping IP ranges.
- D
Implement a VPN connection with policy-based routing to control traffic for specific subnets, avoiding conflicting IP ranges.
- E
Use a third-party appliance in AWS to perform IP address translation between the on-premises and AWS VPC networks.
Show answer and explanation
Correct answers: B, E
Explanation
When dealing with overlapping CIDR ranges, IP address translation is required to map conflicting ranges into unique, non-overlapping ranges. This can be achieved using NAT Gateway or a third-party appliance that performs IP address translation. Other methods, such as AWS Transit Gateway or policy-based routing, cannot directly resolve IP conflicts caused by overlapping CIDR blocks.
- A. Incorrect.
AWS Transit Gateway does not natively resolve overlapping IP ranges. Route propagation helps manage routes but cannot eliminate IP conflicts caused by overlapping CIDR blocks.
- B. Correct.
A NAT Gateway can be used to translate overlapping IP ranges into a non-overlapping space, allowing communication between the on-premises network and the VPC.
- C. Incorrect.
Transit Gateway Network Manager is a monitoring and visualization tool for network resources and does not resolve IP overlap issues.
- D. Incorrect.
Policy-based routing is not sufficient to address overlapping IP ranges directly, as it does not perform IP address translation.
- E. Correct.
A third-party appliance can be configured to handle IP address translation and resolve conflicts caused by overlapping CIDR ranges.