ProtonVPN has a Secure Core mode to improve user privacy and data security by mitigating some of the risks from a compromised VPN server.
A common method to expose VPN traffic is by compromising the server that handles your traffic. This risk is particularly acute when the server is located in a high risk jurisdiction. To mitigate this risk, ProtonVPN employs a technique called Secure Core. This article provides an overview about the attacks that Secure Core mitigates, how it achieves higher VPN privacy, as well as instructions on how to activate Secure Core in ProtonVPN.
A. What does Secure Core protect against?
ProtonVPN’s unique Secure Core architecture allows us to defend against network attacks that other VPNs cannot defend against. A classical VPN setup involves a client passing traffic through a VPN server en-route to the final destination. This means an attacker that has control of the VPN server, or the ability to monitor the network of the VPN server, will be able to match VPN clients with their destination, nullifying the privacy benefits of the VPN.
Such timing/correlation attacks are not difficult to accomplish. In countries with restrictive Internet regulations (China, Russia, Iran, Turkey, etc), or countries with broad surveillance powers (USA, UK, etc), state surveillance agencies typically have the power to coerce either the VPN provider, or the network/server provider of the VPN provider, to assist with such network monitoring. Therefore, even though ProtonVPN is based in Switzerland, we cannot know for sure that our VPN servers in other countries such as the US or the UK are not being monitored and user privacy compromised.
B. How does Secure Core increase VPN privacy?
Secure Core allows us to defend against this threat to VPN privacy by passing user traffic through multiple servers. When you connect to a server in a high risk jurisdiction like the US, your traffic will first go through our Secure Core servers. Therefore, even if our US VPN server is being monitored, an attacker would only be able to follow the traffic back to the edge of our Secure Core network, thus making it far more difficult to discover the true IP address and location of ProtonVPN users.
We have also gone to extraordinary lengths to defend our Secure Core servers. First, servers are located in specifically selected countries with very strong privacy laws (Iceland, Switzerland, and Sweden). Secure Core servers are also located in extra high security datacenters to ensure strong physical security. ProtonVPN infrastructure in Switzerland and Sweden are located in underground datacenters, while our Iceland servers are located within a former military base. Furthermore, Secure Core servers are fully owned by us and also provisioned by us (shipped on-site directly from our offices). Finally, Secure Core servers are connected to the Internet using our own dedicated network with IP addresses that are owned and operated by our own Local Internet Registry (LIR).
These measures provide us with a much higher level of certainty that our Secure Core servers and network are not being tampered with. While there is no such thing as 100% security, Secure Core is just one of the many ways ProtonVPN delivers better VPN security and privacy by protecting against complex attacks other VPNs cannot defend against.
C. How do I activate Secure Core?
Secure Core is a feature included in our Plus and Visionary Plans and can be activated as follows:
With the Windows ProtonVPN application:
- Install ProtonVPN, start the application and log in
- Find and activate Secure Core under the country tab on the left.
- Connect to the available servers in the list underneath.
On MacOS, GNU/Linux, iOS and Android
- Follow the step by step guide to set up ProtonVPN on MacOS, Linux, iOS devices or Android devices
- When selecting a server configuration file, simply choose a config file with a name structure similar to xx-xx-00.protonvpn.com.xxxxxxx.ovpn