Google Professional Cloud Network Engineer Question 197
Single answerGoogle Cloud PlatformYour company is designing a multi-region Google Cloud VPC network to host a new application. The application has strict requirements to avoid IP conflicts with on-premises networks and with other cloud environments during hybrid connectivity. The on-premises network uses RFC 1918 address ranges extensively, including 10.0.0.0/8 and 192.168.0.0/16. What IP address strategy should you select for the VPC subnets to meet these requirements?
- A
Use RFC 1918 address ranges that do not overlap with the on-premises network.
- B
Use publicly routable IP addresses for the VPC subnets to avoid conflicts.
- C
Use privately used public IP (PUPI) addresses for the VPC subnets.
- D
Use random address ranges outside of RFC 1918 that are not publicly routable.
Show answer and explanation
Correct answer: C
Explanation
To avoid IP conflicts in hybrid connectivity scenarios where RFC 1918 address ranges are heavily used on-premises, privately used public IP (PUPI) addresses are the best choice. PUPI addresses are public IP ranges that are not actively used on the internet and can be safely utilized for private networking. This approach ensures that the VPC subnets do not overlap with on-premises networks or other cloud environments, meeting the application's requirements.
- A. Incorrect.
This is a common approach to avoid conflicts, but in this scenario, the extensive use of RFC 1918 ranges in on-premises networks increases the risk of overlap. This option does not guarantee conflict avoidance.
- B. Incorrect.
While using publicly routable IPs could avoid conflicts, it is not recommended because it would expose your internal services to the public internet unless properly secured, and it can lead to security and compliance issues.
- C. Correct.
Privately used public IP (PUPI) addresses are a suitable choice in this scenario. They are publicly routable IP address ranges that are not currently used on the internet and can be utilized privately within the VPC to avoid conflicts with on-premises RFC 1918 ranges.
- D. Incorrect.
Using random address ranges outside of RFC 1918 is not a valid approach because they could overlap with publicly routable IPs or other networks, leading to unpredictable behavior and conflicts.