ExpressVPN has partnered with the Internet Watch Foundation (IWF) to implement a new technology called OpenBoundary, designed to restrict access to websites hosting verified child sexual abuse material (CSAM). The tool effectively blocks VPN users from reaching domains confirmed to contain illegal content, without compromising the core privacy features of the service.
How OpenBoundary Works
OpenBoundary functions as a DNS-level control, preventing access to domains flagged by the IWF as hosting CSAM. Unlike more invasive methods, it does not involve traffic inspection, encryption breaking, or user monitoring. According to ExpressVPN’s chief research officer, Peter Membrey, it’s a deliberately straightforward system designed to maintain user trust.
“OpenBoundary isn’t a breakthrough in cryptography. It’s a simple, well-scoped DNS control used to block access to known child sexual abuse material sites. No broken encryption. No traffic inspection. No monitoring.”
The tool will be rolled out across ExpressVPN, CyberGhost VPN, and Private Internet Access. ExpressVPN is also making OpenBoundary open-source, encouraging wider adoption by other VPN providers, internet service providers (ISPs), and cloud platforms. This move signals a broader industry push to enhance safety measures while preserving user privacy.
Why This Matters
VPNs, while valuable for privacy, can inadvertently facilitate access to illegal content due to their anonymity features. OpenBoundary addresses this issue head-on by selectively blocking known CSAM domains without undermining the fundamental purpose of a VPN.
This approach is significant because it demonstrates that privacy-focused technologies can be deployed responsibly to combat harmful activity without resorting to mass surveillance or intrusive data collection. It also highlights a growing recognition within the VPN industry of the need to balance user privacy with ethical obligations.
The initiative is part of ExpressVPN’s broader “Not on My Network” effort, which aims to develop further safeguards for a safer digital environment. While the company acknowledges that OpenBoundary is not a complete solution to online exploitation, it represents a concrete step toward responsible operation within the VPN sector.
Ultimately, this move sets a precedent for how privacy-preserving infrastructure can be engineered to act against illegal activity without weakening the protections millions of people rely on.
