Is VPN passthrough still relevant?

A VPN passthrough is an obscure component of routers that gets overlooked due to its passive performance. Despite its silent operation, it performs a key action of preventing disagreements between VPNs and older protocols. Most networking devices support and handle VPN traffic without any issues. However, senior routers can have trouble as they do not receive data critical to establishing connections to the web. Hence, a VPN passthrough solves such incompatibility debacles and guarantees that routers agree to accept VPN traffic.

What is a VPN passthrough?

A VPN passthrough is just another stop that web traffic makes before reaching its final destination. To understand its importance and role, we need to revisit some networking principles quickly. All internet-connected devices operate with a public IP address, given to them by the router. Gadgets on the same network are like a big happy family: they peacefully share the same address and connect to the internet.

NAT neatly packages data packets from individual devices, glues identical return (IP) addresses, and sends them on their way. Furthermore, NAT works as a supervisor, checking data packets before delivering them. A VPN strips data packets off their original data used for identification. Then, NAT might no longer recognize packets as they do not present the required details. This confrontation prevents VPN traffic from leaving the network. The good news is that the VPN passthrough restructures this path and fulfills the NAT’s requirements.

So, the VPN passthrough is essential when a VPN or router uses outdated VPN protocols (PPTP, IPSec, and L2TP). Furthermore, the VPN passthrough is a combination of workarounds, designed to adapt and replace outdated protocols with advanced ones. Hence, there are three scenarios when this passthrough is vital:

  • When people use old-time routers. Most modern networking devices have a VPN passthrough integrated.
  • With old protocols. PPTP, L2TP, and IPSec are the trio of outdated technologies that might disrupt the communication between NAT and VPN.
  • With obsolete operating systems. Older OS might use older protocols that won’t match the special NAT provisions.

Do you need to enable it?

As mentioned, most modern routers have a built-in VPN passthrough. However, due to different policies of Internet Service Providers, default configurations might have the feature disabled. To find the setting manually, you need to access the web interface of your router. Do this by typing in the router’s internal IP address as a link into any browser. Since the VPN passthrough is an umbrella term for three workarounds, you will need to look for three main settings. Enable the PPTP, L2TP, and IPSec passthrough set and guarantee that outbound VPN traffic will always reach its destination.

Hence, if you use a modern router and operating system, these configurations are not mandatory. In addition to this, pay attention to the protocols that your VPN provider uses. A VPN should not employ PPTP, L2TP, or IPSec. Atlas VPN prefers the use of current and industry-standard protocols. It operates with IKEv2, which has no issues with NAT.

Is VPN router the same as VPN passthrough?

VPN router and VPN passthrough are distinct concepts, but people seem to treat them as counterparts. In reality, they have very little in common except the fact that they involve routers. A VPN router is a networking device that has a VPN client installed through its web interface. It does not relate to the VPN passthrough at all. The latter guarantees that outbound VPN traffic reaches the internet.

After deployment of modern protocols across the VPN market, the relevance and noteworthiness of the VPN passthrough slowly fade. It was valid and necessary when archaic protocols prevented VPNs from harmonizing with NAT.

Atlas VPN is compatible with NAT, and enabling a passthrough is redundant. Be sure to try out its seamless connections, consistent high-speed performance, and continuous protection.


John C.

John C.


Tags: NAT PPTP IPSec L2TP