Designing Secure Multi-Region Access Using Single VPN

Yes — A Single VPN Entry Point for 7 Regions Is Achievable.

The recommended architecture is a Hub-Spoke model using AWS Transit Gateway with inter-region peering. You terminate a single Site-to-Site VPN in one "hub" region, then use Transit Gateway peering to reach the other 6 regions.

Recommended Architecture

The traffic flow is:

On-Premises → (Site-to-Site VPN) → Hub Region Transit Gateway → (TGW Inter-Region Peering) → Spoke Region Transit Gateway → Spoke VPCs

Here's how to set it up:

1. Pick a hub region (e.g., the one closest to your office for lowest latency).
2. Create a Transit Gateway in each of the 7 regions.
3. Create one Site-to-Site VPN connection from your on-premises router to the hub Transit Gateway. AWS recommends TGW-based VPN over VGW for scalability and ECMP support (source (https://docs.aws.amazon.com/whitepapers/latest/building-scalable-secure-multi-vpc-network-infrastructure/vpn.html)).
4. Create Transit Gateway inter-region peering from the hub TGW to each of the 6 spoke TGWs.
5. Attach your VPCs in each region to their local Transit Gateway.
6. Configure route tables: the hub TGW routes each spoke region's CIDRs to the corresponding peering attachment. Each spoke TGW routes on-premises CIDRs back through the peering attachment to the hub.

This is the pattern described in the AWS hybrid connectivity whitepaper for multi-region (>3 regions) (https://docs.aws.amazon.com/whitepapers/latest/hybrid-connectivity/aws-dx-dxgw-with-aws-transit-gateway-multi-regions-more-than-3.html).

Client VPN vs. Site-to-Site VPN

Site-to-Site VPN is for permanent network-to-network links (office/data center to AWS). It provides 1.25 Gbps per tunnel, supports BGP routing, integrates with TGW route tables, and costs ~$0.05/hr per connection plus data transfer. It reaches all 7 regions through TGW peering from the hub.

Client VPN is for individual user remote access (laptops, remote workers). It costs $0.10/hr per endpoint plus $0.05/hr per active connection. To reach multiple regions, you'd need either an endpoint in each region or VPC peering — neither is ideal for site-level connectivity.

Recommendation: For "office accessing resources across 7 regions," use Site-to-Site VPN on Transit Gateway. Client VPN is the wrong tool for this use case.

Cost Breakdown for 7 Regions

Using US East pricing as reference:

Fixed monthly costs:

• 1 Site-to-Site VPN connection: ~$36 ($0.05/hr × 730 hrs)
• Hub TGW — 1 VPN attachment: ~$36.50 ($0.05/hr)
• Hub TGW — 6 peering attachments (one per spoke): ~$219
• 6 Spoke TGWs — 1 peering attachment each: ~$219
• 6 Spoke TGWs — 2 VPC attachments each (12 total): ~$438
• Hub TGW — 2 VPC attachments (hub VPCs): ~$73
• Fixed total: ~$1,021.50/month

Variable costs:

• TGW data processing: $0.02/GB
• Inter-region data transfer via TGW peering: $0.02/GB (most regions)

The dominant cost is TGW attachments (~$36.50/month each), not the VPN itself. Minimize attachments by consolidating VPCs where possible.

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Summary Recommendation

1. Start with: Site-to-Site VPN → Hub Transit Gateway → TGW inter-region peering to 6 spoke TGWs
2. If operational complexity grows: Migrate to AWS Cloud WAN for policy-driven management
3. If performance/reliability demands increase: Add Direct Connect with DX Gateway, keep VPN as backup
4. Minimize costs by: Using route summarization, placing the hub in the region closest to your office, and consolidating shared services (DNS, inspection) in the hub to reduce inter-region traffic

References: · AWS VPN Pricing (https://aws.amazon.com/vpn/pricing/) · AWS Transit Gateway Pricing (https://aws.amazon.com/transit-gateway/pricing/) · Building a Scalable and Secure Multi-VPC Network Infrastructure