VPN Protocols Explained: WireGuard vs OpenVPN vs IKEv2
Marketing says "military-grade encryption." Here's what actually matters.
⚡ Quick Answer
WireGuard is the best protocol for most users in 2025 — it's faster, more efficient, and uses modern cryptography. OpenVPN remains excellent for maximum compatibility. IKEv2 works well on mobile. Avoid PPTP entirely.
In This Guide
What is a VPN Protocol?
A VPN protocol is the set of rules that determines how your data travels between your device and the VPN server. Think of it as the language your device speaks to create a secure tunnel.
The protocol affects three critical things:
- Speed — How fast your connection runs
- Security — How well your data is protected
- Stability — How reliably the connection stays up
Most VPN apps handle this automatically, but understanding protocols helps you troubleshoot issues and make informed choices.
WireGuard: The New Standard
WireGuard is the newest major protocol, released in 2020 after years of development. It's become the default choice for good reason.
Why WireGuard Wins
Speed: WireGuard is typically 20-50% faster than OpenVPN. The leaner codebase (around 4,000 lines vs OpenVPN's 400,000+) means less processing overhead.
Modern cryptography: Uses ChaCha20 for encryption, Poly1305 for authentication, and Curve25519 for key exchange. These are considered state-of-the-art.
Battery efficiency: The lightweight design uses less CPU, which translates to better battery life on mobile devices.
Quick connections: Handshakes complete in milliseconds, not seconds. Switching networks (WiFi to cellular) is nearly seamless.
WireGuard Concerns
IP address storage: By design, WireGuard keeps the last-used IP address in memory. Privacy-focused providers solve this with wrapper implementations (NordVPN's NordLynx, Mullvad's approach) that regularly rotate keys.
Newer track record: OpenVPN has been audited for decades. WireGuard's shorter history means less time for vulnerabilities to be discovered. That said, multiple audits have found it robust.
OpenVPN: The Reliable Veteran
OpenVPN has been the industry standard since 2001. It's open source, extensively audited, and supported on virtually every platform.
OpenVPN Strengths
Proven security: Two decades of security audits and real-world use. Vulnerabilities get found and fixed. You know what you're getting.
Flexible configuration: Can run on any port (including TCP 443, which looks like regular HTTPS traffic). This helps bypass network restrictions and VPN blocks.
Universal support: Works on everything — routers, old devices, niche operating systems. If a device supports VPNs, it probably supports OpenVPN.
OpenVPN Drawbacks
Slower speeds: The larger codebase and older architecture mean more processing overhead. Expect 10-30% slower than WireGuard on the same server.
Complex setup: Manual configuration requires dealing with certificate files and config files. Most users should stick to apps that handle this automatically.
IKEv2/IPsec: Mobile Champion
IKEv2 (Internet Key Exchange version 2) paired with IPsec provides strong security with excellent mobile performance.
Why IKEv2 Works for Mobile
MOBIKE support: The protocol handles network switching gracefully. Moving from WiFi to cellular doesn't drop your connection.
Native support: Built into iOS, macOS, and Windows. No additional software needed for basic functionality.
Fast reconnection: Dropped connections restore quickly without full re-authentication.
IKEv2 Limitations
Easier to block: Uses fixed UDP ports (500 and 4500), making it identifiable by firewalls.
Closed development: Originally developed by Microsoft and Cisco. The specification is open, but it doesn't have OpenVPN's transparent development history.
Protocols to Avoid
⚠️ PPTP — Never Use This
Point-to-Point Tunneling Protocol dates from 1999. Its encryption has been broken for years. The NSA can crack PPTP connections.
If a VPN provider offers PPTP as your only option, find a different provider immediately.
L2TP/IPsec — Outdated
Not broken like PPTP, but slow and potentially compromised by NSA (per Snowden documents). No reason to use it when better options exist.
SSTP — Windows-Only Concern
Secure but proprietary Microsoft protocol. Works fine, but vendor lock-in and lack of transparency make it less desirable than open alternatives.
Head-to-Head Comparison
| Feature | WireGuard | OpenVPN | IKEv2 |
|---|---|---|---|
| Speed | ★★★★★ | ★★★☆☆ | ★★★★☆ |
| Security | ★★★★★ | ★★★★★ | ★★★★☆ |
| Stability | ★★★★★ | ★★★★☆ | ★★★★★ |
| Mobile Battery | ★★★★★ | ★★★☆☆ | ★★★★☆ |
| Bypasses Blocks | ★★★☆☆ | ★★★★★ | ★★☆☆☆ |
| Audit History | ★★★☆☆ | ★★★★★ | ★★★★☆ |
| Code Lines | ~4,000 | ~400,000 | ~15,000 |
Which Protocol Should You Choose?
For General Use → WireGuard
Fastest speeds, modern security, works great on all devices. This should be your default.
For Bypassing Restrictions → OpenVPN (TCP)
When networks block VPNs, OpenVPN on TCP port 443 looks like regular HTTPS traffic.
For iOS/Mobile (if WireGuard unavailable) → IKEv2
Native support and excellent network switching. Good fallback when WireGuard isn't an option.
For Maximum Privacy → Mullvad's WireGuard
Mullvad's implementation solves the IP storage concern with regular key rotation. See our Mullvad review.
Best VPNs by Protocol Implementation
NordVPN
Best WireGuard Implementation (NordLynx)
NordLynx wraps WireGuard with double NAT to solve the IP storage concern. Fastest speeds in our testing.
Visit NordVPN →Mullvad
Best for Privacy Purists
Open-source WireGuard implementation, anonymous accounts, no email required. We recommend them despite earning $0.
Visit Mullvad →Frequently Asked Questions
Does the protocol affect what I can access? ▼
No. The protocol handles the secure tunnel, but what you access depends on the server location. All protocols let you reach the same content.
Can my ISP see which protocol I use? ▼
They can see encrypted traffic patterns that suggest VPN use, and some protocols are more identifiable than others. OpenVPN on TCP 443 is hardest to detect. WireGuard's UDP traffic is recognizable but still encrypted.
Should I worry about WireGuard's IP storage? ▼
For most users, no. Reputable providers have implemented solutions (NordLynx, Mullvad's approach). The IP is stored in RAM and cleared on disconnect. It's a theoretical concern that's been addressed in practice.
Why do some VPNs offer proprietary protocols? ▼
Some are genuine improvements (NordLynx, Lightway). Others are marketing. Be skeptical of proprietary protocols that haven't been independently audited. We prefer open-source protocols that security researchers can examine.
The Bottom Line
For 95% of users, WireGuard is the right choice. It's faster, more efficient, and uses modern cryptography. OpenVPN remains valuable for bypassing restrictions, and IKEv2 works well as a mobile fallback.
The best VPN providers support all three and let you switch easily. Don't overthink it — pick WireGuard as your default and switch to OpenVPN TCP if you hit connection issues.