What Is OpenVPN? The Ultimate Beginner‘s Guide

In an age where our digital lives are increasingly intertwined with our physical ones, online privacy and security have become paramount concerns. From hackers and cyber criminals to government surveillance and data harvesting by tech giants, the threats to our personal information are numerous and ever-evolving.

Consider these alarming statistics:

• Cybercrime costs the global economy over $1 trillion annually, with damages expected to reach $10.5 trillion by 2025. (Source)
• Over 37 billion records were exposed in data breaches in 2020 alone. (Source)
• Global internet users have an average of 100 passwords to remember. 59% reuse their passwords across multiple accounts, putting their data at risk. (Source)

In this treacherous online landscape, Virtual Private Networks (VPNs) have emerged as an essential tool for safeguarding your privacy and security. And when it comes to VPN protocols, few are as widely trusted and battle-tested as OpenVPN.

What Makes OpenVPN Special?

At its core, a VPN creates a secure, encrypted tunnel between your device and a remote server, preventing anyone from intercepting your data along the way. But not all VPN protocols are created equal. Some, like PPTP, have known security vulnerabilities. Others, like IPsec, can be difficult to configure and may not work well with restrictive firewalls.

Enter OpenVPN. Born out of the open-source software movement, OpenVPN has been vetted and improved by thousands of developers worldwide since its initial release in 2001. This transparency and community scrutiny give OpenVPN a level of trustworthiness that proprietary VPN protocols simply can‘t match.

But OpenVPN isn‘t just secure—it‘s also incredibly versatile. It can run on any port, including TCP port 443 which is used for HTTPS traffic, making it very difficult to block. It supports a wide range of cryptographic algorithms and ciphers, allowing for robust encryption without sacrificing performance.

	OpenVPN	IPsec	WireGuard	PPTP
Security	High	High	High	Low
Speed	Moderate	Fast	Very Fast	Fast
Key Exchange	TLS	IKE	Noise	MS-CHAP
Default Port	1194	500	51820	1723
Open Source	Yes	No	Yes	No

How OpenVPN Works: A Step-by-Step Breakdown

Now that we understand what sets OpenVPN apart, let‘s dive into how it actually establishes a secure connection.

1. TLS Handshake: When you initiate an OpenVPN connection, the first thing that happens is a TLS handshake between your client and the OpenVPN server. This handshake authenticates the server‘s identity and negotiates the encryption parameters for the session.

2. Authentication: Next, the OpenVPN server authenticates your client to ensure you‘re authorized to access the VPN. This can be done with username/password credentials, a static key, or certificates. The latter two options are more secure as they‘re harder to crack than passwords.

3. Tunnel Creation: Once authentication is successful, the OpenVPN client and server establish a secure tunnel. They accomplish this by using the parameters agreed upon during the TLS handshake to encrypt all the data flowing between them.

4. Data Transfer: With the encrypted tunnel up and running, you can now send data through the VPN. When your device sends a packet, OpenVPN encrypts it, encapsulates it, and sends it through the tunnel to the server. The server then decrypts the packet and routes it to its intended destination. Replies follow the reverse path, being encrypted by the server and decrypted by your client.

Here‘s a simplified diagram of this process:

Your Device <--> OpenVPN Client <==encrypted tunnel==> OpenVPN Server <--> Internet

All of this happens seamlessly in the background, giving you a secure and private internet connection without needing to be a cryptography expert. OpenVPN uses the OpenSSL library to handle the heavy lifting of encryption and decryption, benefiting from OpenSSL‘s frequent security updates and optimizations.

Advantages of OpenVPN

So why choose OpenVPN over other VPN protocols? Let‘s review some of its key strengths:

• Security: OpenVPN uses best-in-class encryption standards, including AES, Blowfish, and even ChaCha20/Poly1305 for the latest and greatest in cryptographic security. It supports both SHA-256 and SHA-3 hash functions. Additionally, OpenVPN can provide Perfect Forward Secrecy (PFS) by using ephemeral encryption keys that are discarded after each session.

• Flexibility: OpenVPN can run on any port and can even disguise itself as standard HTTPS traffic. This makes it very difficult for firewalls to block. It‘s also highly customizable through configuration options and plugins.

• Compatibility: There are OpenVPN clients available for virtually every platform, from Windows and macOS to Linux, iOS, Android, and even home routers. This broad compatibility makes it an ideal choice for securing a variety of devices.

• Open Source: Because OpenVPN‘s code is publicly available, it has been thoroughly audited by cybersecurity experts. Any vulnerabilities are quickly caught and patched. Proprietary VPN protocols don‘t have this advantage.

Potential Drawbacks

No technology is perfect, and OpenVPN does have a few potential drawbacks:

• Complexity: OpenVPN can be complex to set up and configure, especially for those who aren‘t tech-savvy. Misconfiguration can lead to security vulnerabilities. However, many VPN providers offer pre-configured OpenVPN setups to mitigate this issue.

• Speed: Due to its focus on security, OpenVPN can be slightly slower than more lightweight protocols like WireGuard. However, on most modern devices and internet connections, this difference is negligible. Advances in hardware acceleration are also helping to close this gap.

• Mobile Battery Usage: The complexity of OpenVPN‘s encryption can take a toll on mobile battery life. For always-on VPN connections on smartphones, a more lightweight protocol like IKEv2/IPSec or WireGuard may be preferable.

OpenVPN Use Cases and Deployment Models

OpenVPN‘s flexibility makes it suitable for a wide variety of use cases, from personal privacy to business security. Let‘s look at a few common deployment models:

Site-to-Site VPN

In this model, OpenVPN is used to connect two or more physical locations, such as office branches. This allows secure sharing of resources and data between sites without the need for expensive leased lines. Each site has an OpenVPN server, and the servers connect to each other to form a mesh network.

Site A <---> OpenVPN Server A <==tunnel==> OpenVPN Server B <---> Site B

Remote Access VPN

This is the most common use case for individual VPN users. Your device connects to a remote OpenVPN server operated by a VPN provider. All your internet traffic is routed through this server, hiding your real IP address and encrypting your data.

Many businesses also use this model to enable secure remote work. Employees can connect to the company‘s OpenVPN server to access internal resources as if they were on the office network.

Remote User <---> OpenVPN Client <==tunnel==> OpenVPN Server <---> Corporate Network  

Peer-to-Peer VPN

OpenVPN can also be configured to enable direct peer-to-peer (P2P) connections without a central server. This can be useful for securely connecting devices in a local network or for direct file sharing between individuals.

In this model, each device runs both an OpenVPN client and server. The devices authenticate each other and establish direct encrypted tunnels.

Device A <---> OpenVPN Client/Server <==tunnel==> OpenVPN Client/Server <---> Device B

Setting Up OpenVPN: A Quick Guide

To get started with OpenVPN, you‘ll need to either subscribe to a VPN service that provides OpenVPN configuration files or set up your own OpenVPN server. The latter option provides more control but requires significant technical knowledge.

For most users, using a reputable VPN provider is the simplest and most secure option. Here‘s a quick guide:

1. Choose a VPN Provider: Select a VPN service that supports OpenVPN and has a good reputation for security and privacy. Some well-regarded providers include ProtonVPN, Mullvad, and ExpressVPN.

2. Download Config Files: Most VPN providers offer pre-configured OpenVPN configuration files. Download these from your provider‘s website or generate them using their configuration tool.

3. Install an OpenVPN Client: There are official OpenVPN clients available for Windows, macOS, iOS, and Android. Many VPN providers also have their own custom clients that simplify the setup process.

4. Import Config Files: Open your OpenVPN client and import the configuration files you downloaded. You may need to provide your VPN username and password or use an authentication file provided by your VPN service.

5. Connect and Verify: Initiate the VPN connection and verify it‘s working by checking your IP address on a site like WhatIsMyIP.com. If it shows the IP of your VPN server instead of your real IP, you‘re all set!

For maximum security, always use the strongest encryption options available and enable features like a kill switch, which will block all internet traffic if your VPN connection drops unexpectedly.

OpenVPN and the Future of VPNs

As powerful as OpenVPN is, it‘s not the only player in the VPN game. In recent years, a newer protocol called WireGuard has been gaining traction. WireGuard aims to be simpler and faster than OpenVPN while still providing robust security.

Feature	OpenVPN	WireGuard
Codebase Size	70,000+ lines	4,000 lines
Speed	Moderate	Very Fast
Encryption	AES, ChaCha20	ChaCha20
Stability	Highly Stable	New, But Promising

While WireGuard shows a lot of potential, it‘s still relatively new and hasn‘t been battle-tested like OpenVPN. For now, OpenVPN remains the gold standard for secure VPN connections.

Looking further into the future, the rise of quantum computing could pose a threat to current encryption methods. Quantum computers, when they become powerful enough, could theoretically break many of the cryptographic algorithms we rely on today.

Fortunately, OpenVPN is already adapting to this potential threat. The latest versions support quantum-resistant ciphers like NTRU, ensuring that OpenVPN connections will remain secure even in a post-quantum world.

The Bottom Line

In the ever-evolving landscape of internet security threats, VPNs like OpenVPN are becoming increasingly essential tools for protecting your privacy and data online. By providing robust encryption, flexible configurations, and broad compatibility, OpenVPN enables secure internet access for everyone from casual web surfers to businesses with complex networking needs.

Whether you‘re working from a coffee shop, accessing sensitive business data, or simply trying to stream your favorite show, OpenVPN ensures that your online activities stay private and secure.

But as with any security tool, proper configuration and use are critical. Always choose a reputable VPN provider, use the strongest encryption settings available, and regularly check for updates to keep your OpenVPN setup current.

By understanding how OpenVPN works and following best practices for its use, you can take a significant step towards reclaiming your privacy and security in the digital age. As our lives become increasingly connected, tools like OpenVPN will only become more vital in protecting our digital identities and information.