A VPN Passthrough is a feature that allows a router to support legacy VPN protocols, enabling the establishment of secure connections over routers that require NAT. IPsec Passthrough and PPTP Passthrough are two types of passthroughs that allow routers to pass through legacy VPN protocols, including IPsec and PPTP, respectively. These features are necessary for organizations using older protocols, such as IPsec or PPTP, and can help solve one of the shortcomings of these protocols. However, they also have disadvantages, such as increased computational time and potential security risks if not implemented correctly. Modern routers often come with passthrough functionality enabled by default, making it easier to implement VPN Passthroughs. Nevertheless, VPN technology is becoming outdated, and more secure, Zero Trust-based technologies are replacing VPNs, offering alternative solutions for organizations seeking robust networking security.