VPN Protocols Explained: OpenVPN, WireGuard, IKEv2 and More

VPN protocols are the set of rules that determine how your data is encrypted, transmitted, and decrypted between your device and the VPN server. The protocol you choose affects your speed, security, and compatibility. In this guide, we'll explain every major VPN protocol in plain English.

Why VPN Protocols Matter

Think of a VPN protocol as the language your device and the VPN server use to communicate. Different protocols offer different trade-offs between speed, security, and compatibility. Choosing the right protocol can mean the difference between a fast, secure connection and a slow, vulnerable one.

WireGuard — The Modern Standard

WireGuard is the newest and most advanced VPN protocol. It was released in 2020 and has quickly become the preferred protocol for most VPN providers.

• Encryption: ChaCha20 (fast, modern alternative to AES)
• Key exchange: Curve25519
• Codebase: Only 4,000 lines of code (vs 100,000+ for OpenVPN) — easier to audit and secure
• Speed: Fastest protocol available, especially on mobile devices
• Best for: Everyday use, streaming, gaming, mobile

Verdict: If your VPN offers WireGuard, use it. It's fast, secure, and efficient.

OpenVPN — The Battle-Tested Veteran

OpenVPN has been the gold standard for over 15 years. While it's being superseded by WireGuard for everyday use, it remains an excellent choice for maximum compatibility.

• Encryption: AES-256-GCM
• Transport: UDP (faster) or TCP (more reliable, bypasses some firewalls)
• Codebase: Open source, extensively audited
• Speed: Slower than WireGuard due to larger codebase and overhead
• Best for: Bypassing restrictive firewalls, maximum compatibility

Verdict: Use OpenVPN when WireGuard isn't available or when you need to bypass strict firewalls.

IKEv2/IPsec — The Mobile Champion

IKEv2 (Internet Key Exchange version 2) is a protocol developed by Microsoft and Cisco. It's particularly well-suited for mobile devices.

• Encryption: AES-256
• Key feature: Automatically reconnects when switching between WiFi and cellular
• Speed: Fast, comparable to WireGuard on some platforms
• Best for: Mobile devices that switch between WiFi and cellular frequently

Verdict: Excellent for mobile use, especially when you're moving between networks.

Lightway — ExpressVPN's Proprietary Protocol

Lightway is ExpressVPN's custom protocol, designed to combine the speed of WireGuard with the reliability of OpenVPN.

• Encryption: AES-256 or ChaCha20
• Key feature: Faster connection times than WireGuard
• Speed: Comparable to WireGuard
• Best for: ExpressVPN users who want maximum speed

Verdict: Only available with ExpressVPN. Good performance, but WireGuard is just as good and available everywhere.

L2TP/IPsec — The Legacy Option

L2TP (Layer 2 Tunneling Protocol) paired with IPsec is an older protocol that's still supported by many VPNs for compatibility.

• Encryption: AES-256 (via IPsec)
• Speed: Slower than WireGuard and OpenVPN
• Security concern: May have been compromised by NSA
• Best for: Legacy devices that don't support newer protocols

Verdict: Only use if no other protocol is available. There are known security concerns.

PPTP — Do Not Use

PPTP (Point-to-Point Tunneling Protocol) is a 25-year-old protocol with critical security vulnerabilities. It can be cracked in minutes with modern hardware.

• Encryption: MPPE (insecure)
• Speed: Fast (because encryption is minimal)
• Security: Compromised — multiple known vulnerabilities
• Best for: Nothing. Do not use PPTP.

Verdict: Never use PPTP. If your VPN only offers PPTP, switch providers immediately.

Protocol Comparison Table

Which Protocol Should You Use?

For 90% of users, the answer is simple: WireGuard. It's fast, secure, and efficient. If your VPN supports WireGuard (and most do in 2026), use it as your default protocol.

If you're in a restrictive network environment (like China or a corporate firewall), switch to OpenVPN with TCP. If you're on a mobile device that switches between WiFi and cellular, IKEv2 is a good choice.

Providers like InterServer VPN support WireGuard and OpenVPN, giving you the best of both worlds.