/System/Library/Frameworks/NetworkExtension.framework/NetworkExtension With the NetworkExtension framework, you can customize and extend the core networking features of iOS and macOS. Specifically, you can: change the system's Wi-Fi configuration; integrate your app with the hotspot network subsystem (Hotspot Helper); create and manage VPN configurations, using the built-in VPN protocols (Personal VPN) or a custom VPN protocol; implement an on-device content filter; create and manage system-wide DNS configurations, using the built-in DNS protocols or a custom on-device DNS proxy.