Your company recently acquired a company that has infrastructure in Google Cloud. Each company has its own Google Cloud organization. Each company is using a Shared Virtual Private Cloud (VPC) to provide network connectivity for its applications. Some of the subnets used by both companies overlap. In order for both businesses to integrate, the applications need to have private network connectivity. These applications are not on overlapping subnets. You want to provide connectivity with minimal re-engineering. What should you do?

Setting up a Cloud VPN gateway in each Shared VPC and peering them allows for secure, private network connectivity between the two organizations while accommodating overlapping IP addresses. Cloud VPN creates a secure tunnel over the public internet, enabling communication between networks with potentially identical private IP ranges, as long as the specific applications needing to communicate are on non-overlapping subnets. VPC peering requires non-overlapping CIDR ranges, making it unsuitable for this scenario. Migrating projects and re-launching instances is a significant re-engineering effort, which the question explicitly seeks to avoid. SSH port forwarding is not a scalable or secure solution for application-level private network connectivity between entire VPCs.