Learn OpenVPN - History, Background & Why OpenVPN

#Introduction

Before building configurations, it is important to understand why OpenVPN exists. VPNs are not a new technology — IPsec has existed since the 1990s, and PPTP was even bundled by Microsoft. But both left behind major problems: IPsec was too complex to configure, while PPTP was insecure.

In episode 1 we trace the evolution of VPNs, the birth of OpenVPN in 2001, the problems it solved, and why even today OpenVPN remains the top choice for millions of organizations. This history is not mere trivia — the architectural decisions James Yonan made two decades ago still shape the way we write configuration in episodes 3 through 22.

#The Evolution of VPNs Before OpenVPN

We start with the two main predecessors of OpenVPN, along with the weaknesses of each that ultimately created the need for a new approach.

#IPsec: Powerful but Complex

IPsec is a family of protocols for securing IP communication at layer 3, using AH and ESP for integrity and encryption. Its security is widely recognized as strong, and to this day IPsec is still used for site-to-site.

The problem lies in complexity. Building an IPsec tunnel requires understanding IKE, ISAKMP, Phase 1 and Phase 2, transform sets, and cipher proposals that must match on both ends. In many implementations, a single wrong character in the configuration is enough to make the tunnel fail with an error that is difficult to debug.

#PPTP: Simple but Insecure

On the other hand, PPTP (Point-to-Point Tunneling Protocol) was popular because it was very easy to configure and already integrated with Windows. Unfortunately, PPTP uses the MS-CHAPv2 authentication protocol, which has been proven to be breakable.

Public security testing shows that PPTP credentials can be cracked within hours. Today PPTP is considered obsolete, and nearly all vendors advise against using it at all.

#OpenVPN Is Born in 2001

It was amid these two extremes that James Yonan started the OpenVPN project in 2001, later working with Francis Dinha to develop and popularize it through the open-source community. The core idea was simple but revolutionary: why not build a VPN on top of the already mature SSL/TLS?

By building on OpenSSL, OpenVPN inherited battle-tested cryptographic standards that are continuously updated. The following verification command shows the OpenVPN version and build running in your lab:

openvpn --version

The output shows the version number, build date, and the linked OpenSSL version. This information is useful when looking up changelogs at github.com/OpenVPN/openvpn.

#The Problems OpenVPN Solved

The birth of OpenVPN was no accident — it answered three concrete problems that plagued IPsec and PPTP.

#Flexibility and Ease of Configuration

OpenVPN is configured through a single plain-text file with no special tools. One directive per line, comments with hash marks, and common errors are easy to spot. The same configuration can be used on both server and client with minor adjustments.

There are no more transform set concepts or phase negotiation. You simply write the port, protocol, certificates, and encryption parameters in one file, then run openvpn --config server.conf to start the daemon.

#Based on TLS, Not Raw IPsec

By using SSL/TLS, OpenVPN leverages years of hard work by the cryptography community. X.509 certificates, renegotiation, perfect forward secrecy, and a variety of cipher suites can all be used directly without being rewritten.

This approach also makes it possible to integrate OpenVPN with an existing PKI in your company. If your organization already has an internal CA, OpenVPN simply requests certificates from it.

#Getting Through NAT and Firewalls

The biggest problem with old VPNs: many networks interfere with exotic tunneling protocols. OpenVPN answers this by encapsulating everything over UDP or TCP, including port 443, which is almost always open in firewalls.

This is why OpenVPN is often the last resort that still works on restrictive hotel, airport, or office networks. To firewalls, OpenVPN traffic looks like ordinary HTTPS.

#Adoption and Ecosystem

Since 2001, OpenVPN has grown into a large ecosystem, not just a single daemon.

#Open Source and Multi-Platform

OpenVPN is available for Linux, Windows, macOS, BSD, Android, and iOS. Clients come in both GUI and CLI flavors. Its open-source nature ensures continuous security audits and customizable features.

The OpenVPN Connect client is the gateway for non-technical users, while a single .ovpn file can be distributed to employees without special training.

Because its configuration format is text-based, clients on different platforms can all use the same file. This is one of the reasons OpenVPN is widely used as a Bring Your Own Device solution in companies.

#Cloudflare WARP and Corporate VPNs

The most visible mass adoption is Cloudflare WARP, which uses the WireGuard protocol — but on the other hand, thousands of corporate VPNs still run on OpenVPN. Many router and commercial firewall distros even bundle OpenVPN as a standard feature.

Another piece of evidence: nearly all commercial VPN providers offer OpenVPN profiles for import into third-party applications. This de facto standard is why OpenVPN skills remain highly sought after in the job market.

#Community and Documentation

OpenVPN is backed by complete documentation at openvpn.net, community wikis, and an active mailing list. Regular releases come out periodically — version 2.7.x, which we use, is the latest stable release at the time this series was written.

#Verifying the History in Your Lab

Let's verify what is installed in your lab, while also seeing the version history available in your repositories:

apt-cache policy openvpn
openvpn --version

The first line apt-cache policy openvpn shows the installed version and the version available for update. Compare it with openvpn --version to make sure you are running the right release before continuing to episode 3.

In addition, make a habit of recording the release date of each version. Knowing which version you are running is very helpful when looking up changelogs and security advisories on the official OpenVPN release pages.

#OpenVPN's Position in Summary

A brief conclusion from this episode:

• IPsec wins on security but loses on ease of configuration.
• PPTP wins on ease but loses decisively on security.
• OpenVPN offers a balance: modern TLS security with simple configuration.
• The ability to pass through NAT and firewalls makes OpenVPN very practical in the real world.
• Its ecosystem is mature: clients for every platform, plugins, and complete documentation.
• OpenVPN 2.7.x is the stable release used as the basis for this series.

By understanding this context, you will appreciate every directive we will learn starting with the next episode.

#Conclusion

Key takeaways:

• IPsec is powerful but complex; PPTP is easy but insecure.
• OpenVPN was born in 2001 by James Yonan as an SSL/TLS-based VPN.
• Three problems it solved: configuration flexibility, TLS security, and NAT/firewall traversal.
• TCP port 443 lets OpenVPN get through strict firewalls.
• OpenVPN is the de facto standard for multi-platform remote access VPNs.
• Save the version info from openvpn --version as a reference for the next episodes.

In the next episode, episode 2, we will dissect core concepts and the main OpenVPN architecture — how SSL/TLS works for key exchange, the difference between tun and tap modes, and the components that make up a connection. This is the theoretical foundation that will make all the configuration in episodes 3 through 22 feel logical.