Is OpenVPN obfuscated?

Answered by Douglas Hiatt

OpenVPN can be obfuscated or scrambled to hide its traffic from firewalls or gateways. This obfuscation feature is designed to make the VPN traffic appear as something else, making it more difficult for network administrators or ISPs to detect and block it.

When OpenVPN obfuscate is enabled, the VPN traffic is disguised to look like regular HTTPS traffic or other types of encrypted traffic. This can help bypass VPN blocks or restrictions that some networks or countries may impose. By making the VPN traffic blend in with other types of encrypted traffic, it becomes harder for firewalls or deep packet inspection (DPI) systems to identify and block it.

To enable OpenVPN obfuscation, you typically need to use a special obfuscation configuration or plugin provided by the VPN service. This configuration or plugin modifies the way OpenVPN packets are sent and received, making them harder to recognize as OpenVPN traffic.

Obfuscation works by adding an extra layer of encryption or obfuscation to the VPN traffic. This can involve encrypting the OpenVPN packets within another layer of encryption, or modifying the packet headers to resemble a different protocol. The exact method used may vary depending on the obfuscation technique employed by the VPN service.

One popular obfuscation technique is called “Stunnel” or “SSL tunneling”. This involves encapsulating the OpenVPN traffic within an SSL/TLS connection, making it appear as regular HTTPS traffic. This can be effective at bypassing firewalls or DPI systems that are configured to block OpenVPN traffic but allow HTTPS traffic.

Another obfuscation technique is called “Obfsproxy” (short for obfuscation proxy). This involves using a proxy server that can obfuscate the VPN traffic. The proxy server acts as an intermediary between the client and the VPN server, modifying the traffic to make it look like something else. This can help bypass VPN blocks that are specifically targeting OpenVPN traffic.

It’s important to note that while obfuscation can help bypass some VPN blocks, it’s not foolproof. Some advanced firewalls or DPI systems may still be able to detect and block obfuscated VPN traffic. Additionally, obfuscation may introduce additional latency or performance overhead, as the VPN traffic needs to be modified and processed before being sent over the network.

In my personal experience, I have encountered situations where obfuscation has been effective in bypassing VPN blocks. In some countries or networks where VPN usage is restricted, enabling obfuscation has allowed me to successfully connect to VPN servers and access blocked websites or services. However, it’s important to keep in mind that the effectiveness of obfuscation can vary depending on the specific circumstances and the capabilities of the network or firewall being used.