VPN Protocols Explained: WireGuard, OpenVPN, and More for UK Users

When you look at VPN specifications, you will often see references to protocols like WireGuard, OpenVPN, and IKEv2. These protocols determine how your VPN encrypts data and establishes connections, and choosing the right one can significantly affect your speed, security, and reliability. This guide explains each major protocol in plain English for UK users.

What Is a VPN Protocol?

A VPN protocol is the set of rules that governs how data is transmitted between your device and the VPN server. Think of it as the language your device and the server use to communicate securely. Different protocols offer different trade-offs between speed, security, stability, and compatibility.

Most modern VPN apps handle protocol selection automatically, but understanding the options allows you to optimise your connection for your specific needs. Whether you prioritise speed for streaming, security for sensitive work, or stability for reliable connections, the right protocol choice matters.

WireGuard: The Modern Standard

WireGuard has rapidly become the gold standard VPN protocol since its official release. It uses state-of-the-art cryptography, has a remarkably small codebase (approximately 4,000 lines compared to OpenVPN's 600,000+), and delivers exceptional performance.

For UK users, WireGuard typically provides the fastest speeds of any protocol. In our testing, WireGuard connections retained 85-95% of baseline internet speeds, significantly outperforming OpenVPN. Connection establishment is nearly instantaneous — typically under one second — making it ideal for mobile users who frequently switch between Wi-Fi and mobile data.

The small codebase is a significant security advantage. With fewer lines of code, there are fewer potential vulnerabilities, and the entire protocol can be thoroughly audited. WireGuard is available on NordVPN (as NordLynx), Surfshark, CyberGhost, Mullvad, PIA, Proton VPN, and most other major providers.

OpenVPN: The Proven Veteran

OpenVPN has been the industry standard for over two decades. It is open source, extensively audited, and highly configurable. While it does not match WireGuard's speed, it remains a rock-solid choice with a proven security track record.

OpenVPN operates in two modes: UDP (faster, less reliable) and TCP (slower, more reliable). TCP mode is particularly useful when connecting from networks that block VPN traffic, as it can operate on port 443 — the same port used by HTTPS — making it indistinguishable from normal web browsing.

For UK users, OpenVPN is the best fallback protocol when WireGuard is unavailable or when you need maximum compatibility. It works on virtually every platform and is the most widely supported protocol across VPN providers. Speed is adequate for all everyday tasks, though you may notice a difference during speed-intensive activities like 4K streaming.

IKEv2/IPSec: The Mobile Champion

IKEv2 (Internet Key Exchange version 2) paired with IPSec is particularly well-suited for mobile devices. Its standout feature is MOBIKE support, which seamlessly handles network transitions. When you move from your home Wi-Fi to mobile data, or between different Wi-Fi networks, IKEv2 re-establishes the connection almost instantly without dropping your VPN tunnel.

For UK commuters who frequently switch between Wi-Fi and mobile data during train journeys or while moving between locations, IKEv2 provides the most seamless experience. Speed is competitive with WireGuard in many scenarios, and the protocol is natively supported on iOS and Windows, requiring no additional software.

Proprietary Protocols

Several VPN providers have developed proprietary protocols. NordLynx (NordVPN) is built on WireGuard with an additional double NAT system for enhanced privacy. Lightway (ExpressVPN) is a custom protocol designed for speed and reliability. Chameleon (VyprVPN) is designed to defeat VPN blocking through traffic obfuscation.

These proprietary protocols generally offer excellent performance and are specifically optimised for their respective services. Use our VPN comparison tool to see which protocols each provider supports.

Which Protocol Should UK Users Choose?

For everyday browsing, streaming, and general use, WireGuard or a WireGuard-based protocol is the best choice. It offers the fastest speeds and strongest modern encryption. For maximum compatibility and working on restrictive networks, OpenVPN TCP is the most reliable option. For mobile use with frequent network switching, IKEv2 provides the smoothest experience.

Most VPN apps have an automatic protocol selection feature that chooses the best protocol based on your current network conditions. For most UK users, this automatic selection works well and requires no manual intervention.

Conclusion

Understanding VPN protocols helps you get the most from your VPN service. While WireGuard has emerged as the clear leader for most use cases in 2026, OpenVPN and IKEv2 remain valuable tools for specific situations. The good news is that all major VPN providers now support modern protocols, ensuring UK users can enjoy fast, secure, and reliable VPN connections regardless of their chosen provider.