Subsidiary US (10.0.0.0/12) Provider / region GCP · us-west1 (Oregon) Environment prod VPC Global, custom-mode (us-gcp-prod-vpc) Region block 10.4.0.0/16 (us-west1) Subnets 4 regional subnets — one per tier, each spanning all 3 zones 1. How GCP differs from AWS The same four-tier design maps onto
Subsidiary US (10.0.0.0/12) Provider / region AWS · us-west-2 (Oregon) Environment prod VPC CIDR 10.1.0.0/20 (4,096 addresses) Subnets 12 — 4 tiers × 3 availability zones 1. Where this VPC sits in the plan The VPC inherits its range top-down from the enterprise IPAM hierarchy:
Version 1.0 Date 2026-06-22 Status Reference design Scope 3 subsidiaries (US, Japan, UK) · AWS, GCP, Azure · on-premises datacenters Supernet 10.0.0.0/8 (RFC 1918) 1. Purpose and scope This document defines a single, hierarchical IPv4 addressing scheme and the governance model that keeps it accurate across multiple