Moderate NAT is a feature useful mainly to online gamers. Depending on your threat model, enabling this setting makes you slightly more vulnerable to correlation attacks, but it can solve connection problems when playing multiplayer online games, having video conversations using WebRTC, or other activities that require a direct peer-to-peer connection.
The setting should be familiar to anyone who owns a games console (on Xbox devices it is called NAT Type Moderate, while on PlayStation devices it is called NAT Type 2).
Moderate NAT is a feature available to everyone on a paid Proton VPN plan. If you are on our Free plan, you can upgrade to unlock this and many other features. To do this, log in to account.protonvpn.com, go to Subscription → Plans, and select a paid plan.
What is NAT?
Network address translation (NAT) maps the IP address of your device to an external IP address that can be accessed from the internet.
NAT is typically performed on a router, but when using a VPN, it is performed on the VPN server.
NAT options
Strict NAT
Strict NAT randomly maps the connection between the VPN server’s IP address and the IP address of your device. This is good for privacy because it makes it more difficult to correlate traffic between the two devices. An outside observer cannot see that two internet connections come from the same device.
Because it is good for privacy, strict NAT is enabled by default for all Proton VPN users. However, it prevents direct connections with others on the internet, and can therefore cause problems when playing multiplayer online games. These problems can include:
- Slow connection speeds
- High ping rates (resulting in lag)
- Problems joining or hosting multiplayer games
- Not being able to hear your teammates when playing games
Other issues include:
- Slower or less reliable videoconferencing sessions using WebRTC-based systems
- Unreliable Slack connections
Unless you are an online gamer who is experiencing such problems, we strongly recommend leaving strict NAT enabled.
Moderate NAT
Moderate NAT disables randomization of the mapping between the VPN server and your device. This slightly reduces your privacy. but allows direct connections to be established with other users, thus eliminating the problems strict NAT can cause for online gamers.
If you are experiencing connection problems when online gaming, enabling moderate NAT should solve your issues.
How to use moderate NAT
Windows and macOS
1. On Windows, open the Proton VPN app and go ≡ (top right) → Settings → Connection tab.
On macOS, open the Proton VPN app and go to the Menu bar → Preferences → Connection tab.
2. Toggle the Moderate NAT switch on to enable moderate NAT, or off to disable it.
Android and iOS/iPad OS
Open the Proton VPN app and go to Settings (Android ≡ → Settings) → Advanced → Moderate NAT and toggle the switch on to enable moderate NAT, or off to disable it.
Linux
Open the Proton VPN app and go to Menu (V) → Settings → Connection and toggle the Moderate Nat switch on.
On our old (v3) Linux CLI tool, enable non-standard ports with the following command:
protonvpn-cli config --moderate-nat enable
And disable them with:
protonvpn-cli config --moderate-nat disable
