OpenVPN vs. Modern WireGuard® Architecture

See how Defguard's WireGuard-based solution compares to legacy OpenVPN. Select a topic to explore the differences.

OpenVPN Performance

OpenVPN runs in userspace, requiring data to pass between kernel and application space for every packet. This creates significant overhead.

  • Runs in userspace (slow context switching)
  • 100,000+ lines of code to process
  • Multi-second connection establishment
  • Drops connection on network changes
Result: ~50-100 Mbps typical throughput

Defguard + WireGuard® Performance

WireGuard operates directly in the kernel with a minimal, audited codebase. Packets never leave kernel space during encryption.

  • Runs in kernel space (zero context switching)
  • ~4,000 lines of auditable code
  • Sub-100ms connection establishment
  • Seamless roaming between networks
Result: Near-gigabit throughput

OpenVPN Security Model

OpenVPN uses legacy TLS/SSL with configurable cipher suites, creating complexity and potential misconfiguration risks.

  • Multiple cipher options (easy to misconfigure)
  • Complex certificate management
  • Large attack surface (100k+ LOC)
  • Stateful connections (vulnerable to attacks)

Defguard Security Model

WireGuard uses modern, fixed cryptographic primitives with no configuration options—eliminating misconfiguration vulnerabilities.

  • Fixed modern cryptography (ChaCha20, Curve25519)
  • Simple key exchange (no PKI complexity)
  • Minimal attack surface (~4k LOC)
  • Stateless design (cryptokey routing)

OpenVPN Authentication

OpenVPN's MFA is typically bolt-on, authenticating only at login time. Once connected, the tunnel stays open.

  • Login-time 2FA only
  • Requires third-party plugins
  • Certificate + password combo
  • No per-connection reauthentication

Defguard True MFA

Defguard implements protocol-level MFA. Every connection attempt can require fresh authentication with multiple factors.

OpenVPN Management

OpenVPN Access Server provides basic management, but advanced features require complex configuration or third-party tools.

  • Manual client configuration distribution
  • Limited SSO integration
  • No real-time config sync
  • Basic user management UI

Defguard Enterprise Management

Defguard provides comprehensive management features designed for enterprise-scale deployments.

OpenVPN Codebase

OpenVPN's large C codebase has accumulated technical debt over 20+ years, making security audits challenging.

  • 100,000+ lines of C code
  • Memory safety vulnerabilities possible
  • Complex dependency chain
  • Difficult to audit comprehensively

Defguard Codebase

Defguard is written entirely in Rust, eliminating entire classes of vulnerabilities at compile time.

  • Memory-safe by design (Rust)
  • WireGuard: ~4,000 audited lines
  • Core open-source (Apache 2.0)
  • Public penetration test reports
  • Reproducible builds

Why WireGuard is Faster Than OpenVPN

Your remote teams deserve a VPN that doesn't slow them down. Here's the performance gain when you migrate from OpenVPN to WireGuard.

3x Faster Throughput

WireGuard's kernel-level processing delivers near-gigabit speeds. Large file transfers, video calls, and cloud applications run without the latency tax of OpenVPN.

Instant Connections (<100ms)

WireGuard's stateless handshake connects instantly. No more waiting seconds for OpenVPN to negotiate ciphers and establish tunnels.

Seamless Network Roaming

Switch from Wi-Fi to cellular without dropping your connection. WireGuard maintains the tunnel transparently—OpenVPN requires reconnection.

Enterprise VPN Features Missing from OpenVPN

Defguard includes enterprise capabilities that OpenVPN Access Server doesn't offer—making large-scale VPN deployments manageable.

Zero-Touch Enrollment

Deploy VPN to thousands of devices without manual configuration. Integrate with Intune, GPO, or your existing MDM. Users launch the app and connect—no setup required. Learn more in our 1.6 release notes →

Pre-logon VPN for AD

Enable Windows login against Active Directory before user authentication. Critical for remote workers who need domain resources from day one. See documentation →

Biometric MFA

Use your phone's biometrics (Face ID, fingerprint) to authenticate desktop VPN connections. True multi-factor without tokens or codes. Learn about MFA →

Trusted by Organizations Worldwide

Companies have already made the switch from legacy VPNs to Defguard's modern architecture.

Trusted by:

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OpenVPN Access Server vs. Defguard: Full Feature Comparison

A detailed comparison showing why enterprises are replacing OpenVPN with WireGuard-based solutions like Defguard.

Feature Defguard OpenVPN Access Server
VPN Protocol WireGuard® — Kernel-level, ~4k lines of code OpenVPN — Userspace, 100k+ lines of code
Typical Throughput Near-gigabit (depends on hardware) 50-100 Mbps typical
Connection Time <100ms (instant) 2-5 seconds
Network Roaming Seamless — maintains connection Drops and reconnects
MFA Implementation Protocol-level, per-connection Login-time only, plugin-based
Biometric Auth Yes — Mobile biometrics for desktop No
Zero-Touch Enrollment Yes — MSI, PKG, GPO, Intune Limited — manual config distribution
Pre-logon VPN (AD) Yes — Connect before Windows login No
SSO Integration Native OIDC — Entra ID, Okta, Google, etc. Limited — SAML with extra config
Real-time Config Sync Yes — Changes push instantly No — Manual redistribution
Built-in Firewall ACLs Yes — NFTables/PF management Basic access rules only
Open Source Core — Server, gateway, and clients Partially — Community Edition limitations
Self-Hosted Yes — Full data sovereignty Yes
Language Rust (memory-safe) C (memory vulnerabilities possible)

How to Migrate from OpenVPN to WireGuard

Moving from OpenVPN to Defguard doesn't require a forklift upgrade. Follow this step-by-step OpenVPN migration guide for zero downtime.

1

Deploy Defguard Alongside OpenVPN

Install Defguard on your infrastructure using Docker, Kubernetes, or our one-line install script. Both VPN solutions can run in parallel.

2

Configure SSO & User Sync

Connect Defguard to your identity provider (Entra ID, Okta, Google, LDAP). Users are automatically provisioned—no manual account creation.

3

Pilot with Power Users

Roll out Defguard clients to a pilot group. They'll immediately notice the performance improvement and seamless reconnections.

4

Enterprise Rollout

Use zero-touch enrollment to deploy to all users via Intune, GPO, or your MDM. Decommission OpenVPN when ready.

Ready to Leave OpenVPN Behind?

OpenVPN was revolutionary in its time, but the world has moved on. WireGuard represents the next generation of VPN technology, and Defguard makes it enterprise-ready with the management features, security controls, and deployment options your organization needs.

Join the organizations that have already made the switch to faster, more secure, and easier-to-manage VPN infrastructure.

OpenVPN Migration FAQ

How much faster is WireGuard compared to OpenVPN?

WireGuard is significantly faster than OpenVPN—typically 3x or more in real-world conditions. This is because WireGuard operates at the kernel level with only ~4,000 lines of code, while OpenVPN runs in userspace with over 100,000 lines. WireGuard's stateless design also enables instant connections (<100ms) versus OpenVPN's multi-second handshakes.

Can I migrate from OpenVPN Access Server to Defguard?

Yes. Defguard is designed as a complete replacement for OpenVPN Access Server. It provides all enterprise features including user management, SSO integration, MFA, and centralized administration—but with the performance benefits of WireGuard. Our documentation includes step-by-step migration guides.

Does Defguard support the same authentication methods as OpenVPN?

Defguard supports more authentication options than OpenVPN. In addition to TOTP and certificate-based auth, Defguard offers biometric MFA (using mobile device biometrics for desktop authentication) and native SSO integration with providers like Microsoft Entra ID, Google Workspace, Okta, and JumpCloud.

How does Defguard handle network changes compared to OpenVPN?

WireGuard handles network changes (like switching from Wi-Fi to cellular) seamlessly without dropping connections. OpenVPN typically loses the connection during network transitions and requires reconnection. This makes Defguard ideal for mobile workers and users who frequently change networks.

Is Defguard open-source like OpenVPN?

Defguard's core components are open-source under the Apache 2.0 license, including the server (Core), gateway, and clients. Some enterprise features require a license. All core code is fully auditable, and we publish public penetration testing reports.

Can I deploy Defguard alongside my existing OpenVPN setup?

Absolutely. Many organizations run Defguard in parallel with their existing OpenVPN infrastructure during migration. You can gradually move users to Defguard while keeping OpenVPN operational, ensuring zero downtime during the transition.

What enterprise features does Defguard offer that OpenVPN doesn't?

Defguard includes features not available in standard OpenVPN: true protocol-level MFA (not just login-time auth), biometric authentication via mobile, zero-touch enrollment at scale, pre-logon VPN for Active Directory, real-time configuration sync to all clients, built-in Access Control Lists with firewall management, and comprehensive audit logging with SIEM integration.