Networking — VPC, Subnets & Firewall Rules
Use Google's global VPC with regional subnets and control traffic via firewall rules.
A GCP VPC is distinctive in being global: a single VPC spans all regions, and subnets are regional (each has a CIDR in one region) but all belong to one global network, so resources in different regions communicate over Google's private backbone without peering. This simplifies multi-region architectures dramatically compared with the per-region VPCs of other clouds. You still design tiers with subnets and route control, with Cloud NAT giving private instances outbound internet access.
A single nationwide company intranet where every regional office (subnet) is already on the same private network — no leased lines to connect branches. Security desks (firewall rules) check badges (network tags) at each office rather than at the perimeter of each separate building.