Private connectivity vs VPN: when to upgrade your network architecture

A VPN gives you encrypted connectivity over the public internet. Private connectivity (Direct Connect / ExpressRoute / Interconnect) gives you a dedicated path with steadier latency and higher throughput but it usually doesn’t encrypt traffic by default, so you often layer IPsec or MACsec on top. 

Upgrade when VPN jitter breaks SLOs, tunnel sprawl becomes ops debt, or you need predictable bandwidth for replication and AI data pipelines. 

What we’re comparing

You can’t pick up the right tool if you’re mixing transport, encryption, and routing in the same sentence.

• VPN (site-to-site IPsec): encrypted tunnels over the public internet. AWS calls each tunnel “an encrypted link,” and a connection ship with two tunnels for HA. 
• Private connectivity: dedicated transport from your edge to the provider edge (BGP, circuits, cross-connects). Great for consistency. Not automatically encrypted on most platforms. 

How VPN behaves in production

VPN works fast. Then traffic shows up and starts acting like traffic.

What VPN is good at

This is why teams start here.

• You can deploy it in days, not weeks.
• You get encryption by design (IPsec).
• It’s fine for bootstrap migrations, admin access, and “good enough” hybrids. 

Where VPN starts hurting

These are the failure modes I see in tickets.

• Jitter and random loss. Your tunnel is stable; the internet path isn’t.
• Throughput ceilings. Encryption and tunnel count become the throttle.
• Tunnel sprawl. One tunnel becomes 20, then nobody remembers why half exists.

If you’re “fixing the VPN” every month, you’re already paying the upgrade tax—just in engineer hours.

How private connectivity behaves in production

Private connectivity buys you a cleaner transport layer. It doesn’t buy you security unless you configure it.

What you get

This is what people actually pay for.

• More consistent latency and throughput than internet paths (especially under load). 
• BGP-based routing. You can route traffic with explicit preferences and failover instead of praying.

What you don’t get by default: encryption

This is the part that security reviewers will flag, correctly.

• Amazon Web Services: Direct Connect traffic is not encrypted by default. AWS says you must use transit encryption options (IPsec overlays, MACsec on supported links). 
• Microsoft Azure: ExpressRoute provides private connectivity but doesn’t encrypt data in transit by default; Microsoft tells you to add encryption and security measures. 
• Google Cloud: Google documents HA VPN over Cloud Interconnect specifically to encrypt traffic traversing Interconnect. 

When to upgrade: the triggers that justify the work

If you’re not seeing these, stay on VPN and spend money elsewhere.

Upgrade to private connectivity when you hit two or more of these:

1. Replication misses windows. Database/DR sync falls behind because latency and loss swing.
2. Steady high-volume data movement. Large backups, model artifacts, embeddings, logs—every day.
3. You’ve built a tunnel zoo. Many sites, many VPCs/VNETs, many peers.
4. SLOs care about tail latency. p95/p99 is the product, not a vanity metric.
5. Compliance wants controlled transport. Then you add encryption on top (IPsec/MACsec), because “private” ≠ “encrypted.” 

Decision matrix

This is the table I’d drop into a design review.

The pattern that usually wins: private transport + encrypted overlay

You don’t have to choose “VPN or private.” You can stack them.

• Private link for the path
• IPsec on top for encryption
• BGP underneath for routing control

All three major clouds document some version of this (Direct Connect + VPN/IPsec, ExpressRoute + additional encryption options, HA VPN over Interconnect). 

Migration plan that doesn’t torch prod

Cutovers should be reversible. If they aren’t, you’re gambling.

1. Inventory and fix CIDRs first. Overlaps will ruin your day.
2. Stand up private connectivity in parallel. Don’t rip-and-replace the VPN on day one.
3. Bring up BGP with route filters. Only advertise what you mean to advertise.
4. Shift traffic by routing preference. Change route preference; don’t restart fleets.
5. Keep VPN as failover until you trust the link. Then decide if you keep it as “break glass.”

Where AceCloud fits

This matters if you’re building hybrid or multi-cloud and want consistent primitives.

AceCloud.ai documents IPsec VPN and private connectivity options as part of its cloud networking stack, plus isolated VPC networking you can use to segment environments.
If you need routing control without new hardware, they also position “virtual routers” with support for VPN types like IPsec and GRE.

For internet-facing applications, layering in secure CDN solutions helps extend that private, controlled architecture to the edge. A secure CDN can offload TLS termination, provide DDoS mitigation, enforce WAF policies, and cache static or dynamic content closer to users, reducing origin load while improving performance and resilience. In hybrid or multi-cloud setups, this also gives you a consistent security perimeter across providers.

(You still do the same engineering work: route design, failover design, encryption policy. The provider just gives you the building blocks.)

Conclusion

Stay on VPN when you need encrypted connectivity fast and your workloads tolerate internet behavior. Upgrade to private connectivity when network variance starts breaking SLOs, data transfer becomes steady and heavy, or tunnel sprawl becomes an ops problem. Then add encryption deliberately because private transport is usually not encrypted by default on AWS, Azure, or Google Cloud.