Amazon Virtual Private Cloudhigh

• AWS VPC is regional with CIDR /16-/28.
• OpenStack Networks project-scoped L2 with flexible CIDR.
• AWS requires IGW for public.
• OpenStack provider nets or floating IPs.

Virtual Network (VNet)high

• Azure VNets are strictly regional Layer 3 overlays scoped to one subscription with no L2 VLAN support ().
• VNets and subnets creation free, but subnets min /29 with Azure reserving 5 IPs per subnet ().
• Managed via ARM REST APIs/PowerShell/CLI vs Neutron REST API.
• Isolated per subscription; peering for cross-VNet connectivity vs OpenStack project networks connected via routers.

VPC (VPC Network)high

• Region-scoped: a VPC network is created in a specific datacenter region and resources must be in that same region to be attached, whereas OpenStack Neutron networks/subnets are generally available across all AZs in a region and attachments are controlled by network reachability rather than an explicit region slug ().
• Resource migration is limited: Droplets require snapshot/recreate to move between VPCs and some resources (Kubernetes clusters, load balancers, NAT gateways) cannot be migrated between VPCs, whereas in OpenStack you typically can attach/detach ports or move router interfaces without recreating servers (behavior depends on deployment, but Neutron’s object model supports it) ().
• NAT is a managed NAT Gateway with tiered capacity (1–16 increments; each increment gives 25 Mbps symmetrical bandwidth and 100 GiB outbound transfer/month) and can be set as the default gateway for the VPC, whereas OpenStack commonly expresses egress via Neutron routers with SNAT and does not use this specific ‘size tier’ model ().
• Security-policy coupling differs: DigitalOcean notes Cloud Firewall rules affect both public and VPC traffic and rules must specify whether they apply to the public or private IP range, whereas in OpenStack security groups are generally applied to ports and are not framed as “public vs private IP range” rule modes ().

VPC Networkhigh

• GCP VPC is global (spans all regions) whereas OpenStack Neutron networks are project-scoped and region-local.
• GCP uses shared VPC for cross-project networking (requires org-level config); OpenStack uses shared networks via admin.
• Subnets in GCP are regional, auto-mode creates one per region automatically; OpenStack requires explicit subnet creation.
• GCP VPC Flow Logs per-subnet; OpenStack has no native equivalent without external tools.

Networkshigh

• Private networks (vSwitch-like but called Networks) created via API, up to 10.0.0.0/8 subnets, attach to servers/LBs.
• CCM supports route controller for pod networking when enabled; no native provider networks like OpenStack.
• Limited to Hetzner regions, IPv4 only for private (IPv6 public).
• Networks are free with no usage charges, unlike potential metering in OpenStack clouds ().