What Is OpenVPN?

How OpenVPN keeps your internet traffic private and safe

VPN concept image

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OpenVPN is a popular and highly secure SSL-based tunneling protocol used with VPNs (virtual private networks. Offering superior protection for data traffic and support for virtually every platform, OpenVPN is considered one of the best VPN protocols in use today.

Here's a closer look at OpenVPN, and why millions rely on it to stay private and secure on the web.

A Brief History of OpenVPN

The OpenVPN project was founded by James Yonan, Co-Founder and CTO of OpenVPN Technologies. Initially released in 2001, OpenVPN is a SSL-based encryption and authentication protocol published under the GNU General Public License (GPL). Today, millions of individuals and businesses rely on OpenVPN for privacy and security on the web.

What Is OpenVPN?

Unlike other VPN protocols (for example, L2TP and IKEv2) that use IPSec encryption, OpenVPN uses SSL for data encryption. SSL is a standard security technology used for establishing secure point-to-point or site-to-site connections. It's commonly used to provide security and encryption for web-based financial transactions, email, and other highly sensitive data.

OpenVPN supports all major operating systems in use today (Mac, Windows, and Linux), as well as Android and iOS. It also supports lesser-known platforms, including OpenBSD, FreeBSD, NetBSD, QNX, and Solaris. In addition to its strong encryption standards, OpenVPN is great at outsmarting firewalls, network address translators (NATs), and prohibitive geo-restrictions.

How OpenVPN Works

OpenVPN is a tunneling protocol that establishes a private connection between a VPN client and a VPN server. The data inside the tunnel is fully encrypted, which means it can't be seen or intercepted by outsiders. This includes your ISP, search engines, websites, marketers, and hackers.

Here's how it works is:

  1. The OpenVPN client encrypts your data packets before they exit your computer or device.

  2. The encrypted data packets are sent along to the OpenVPN server, which decrypts the data with a secret cryptographic key.

  3. The decrypted data is sent out to the internet to the server specified in your request, for example, https://netflix.com.

  4. The internet server receives the data request, and sends its data back to the OpenVPN server.

  5. The OpenVPN server encrypts the data from the internet server and sends the encrypted data to your computer or device.

  6. The OpenVPN client on your computer decrypts the data with its cryptographic key.

OpenVPN Protocols

Here's quick overview of some of the protocols and standards OpenVPN uses to establish secure connections.

  • Authentication: OpenVPN has two authentication modes. It can use a pre-shared static key between peers, or use SSL/TLS and certificates for authentication and key exchange.
  • Encryption: OpenVPN features up to 256-bit encryption via OpenSSL, a full-featured toolkit for the Transport Layer Security (TLS). For even more robust security, it can use AES, Camellia, 3DES, and CAST-128.
  • Ports: OpenVPN is designed to run over both TCP and UDP transports, and offers excellent performance over UDP (a speedier protocol than TCP).

Where Can You Get OpenVPN?

At this point, you may be wondering how to get a VPN service that uses OpenVPN. The good news is, most major VPN providers offer OpenVPN to their subscribers. Once you've chosen your preferred VPN provider, you can head over to their website and download the software.