What Is a VPN Passthrough? How Does It Work?

Last Updated: September 21, 2021

Jason

Jason

You might have seen the term “VPN Passthrough” many times while searching about the working of a VPN and the best VPN services out there.
What is a ‌VPN‌ Passthrough and How Does it Work?
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You might have seen the term “VPN Passthrough” many times while searching about the working of a VPN and the best VPN services out there.

However, when you tried going through this information, you found it hard to understand owing to the technical jargon used for explaining it.

Don’t worry as here we will explain to you what a VPN‌ Passthrough is and how it works in simple language.

Plus, you will also get to know how a VPN Router and a VPN Passthrough are different from each other if you actually require a VPN Passthrough or not, and how you can use it.

What Is a VPN Passthrough?

A VPN Passthrough is a technique to link two secured networks through the internet.

When you enable it on the network, it lets the VPN traffic to pass the internet since old VPN protocols, like LT2P and PPTP, do not identify it and so block it.

It aids the systems connected to the router to enter a remote network and set up outbound VPN connections.

A VPN Passthrough is an in-built feature of the router.

How a VPN Passthrough Works

VPN‌ passthrough

If you have a VPN client set up on your system, then you would like to link it to a server of VPN in order to use the VPN services provided by this client.

You would have to establish this VPN connection so that the VPN traffic can pass through the router.

Every router is different from the other with its different in-built features. This means some of them can block the technology required to access a VPN connection.

In other words, the features of a router can stop your VPN client from creating the outbound VPN connection.

One of the in-built features that you will find in a lot of routers is the NAT or Network Address Translation. It is a standard feature found in several routers, which can block your VPN connection.

NAT filters the traffic to pass through the wider internet network and your network, ensuring that you only get the data you requested for.

This way NAT protects you from potential security hazards, such as malware, hackers, and viruses. Plus, NAT fixes the big issue that we face while using IPv4, that is, a shortage of IPs.

But, this feature of NAT can face incompatibility problems when outdated VPN Protocols try to pass through.

These old VPN Protocols include L2TP or Layer Two Tunneling Protocol, PPTP or Point-to-Point Tunneling Protocol, and IPsec or Internet Protocol Security.

They do not provide sufficient details to NAT in order to let it determine if these are security threats or secure connections. Due to this uncertainty, NAT blocks the VPN Protocols to protect the end-user.

This issue can be resolved with a passthrough, which is also known as L2TP Passthrough, IPsec Passthrough, or PPTP Passthrough as per the specific VPN protocol you’re using.

This passthrough facilitates VPN connections or VPN Protocols to pass the router and link to the server of the VPN.

The Difference Between a VPN Passthrough and A VPN Router

Vpn Router

There is also a device known as a VPN router, which is different from a VPN Passthrough.

A passthrough is an in-built feature that enables VPN traffic to pass a router. It does not do anything else apart from this.

However, a VPN router is a hardware device that has preset VPN components or a house router in which a VPN client has already been set up for running.

A VPN router encrypts the traffic and safeguards all devices that are linked to your network.

Is a Passthrough Necessary?

A Passthrough is a vital part of the procedure that enables your device’s VPN clients to function.

However, it’s not necessary. This is because many new routers now come with an in-built VPN Passthrough.

So, you need a Passthrough only if your VPN client uses old VPN Protocols, including PPTP, L2TP, or IPsec. Moreover, if you use a free VPN, then also it is very likely that it uses outdated VPN Protocols.

More reliable and latest protocols are available in the market now, like Internet Key Exchange version two (IKEv2/IPsec) and OpenVPN.

These updated protocols can easily traverse NAT without any Passthrough, which makes the latter useless. You only have to activate and link your VPN.

Furthermore, you might require a VPN Passthrough if your PC has an old OS or operating system.

IKEv2 and OpenVPN are compatible with operating systems till Windows XP. This means in case you have an OS older than this, then you would require a VPN Passthrough.

How to Enable a VPN Passthrough

VPN

If you require a VPN Passthrough, then don’t fret as a majority of the new routers have a pre-installed VPN Passthrough.

So, if you have the current VPN Protocols, then you do not have to worry about setting up a Passthrough.

However, if you have IPsec/LT2P or PPTP VPN Protocols, then you would require a VPN Passthrough.

Most of the routers activate it by default, but sometimes you might have to start it manually on your router.

You can do so by following these steps:

  1. First, you must check the instruction manual of your router to know its exact IP address.
  2. Then, you have to open an internet browser on your computer.
  3. After this, you must enter the IP address of your router administration program in the URL space provided.
  4. Then, you need to enter the ID and password of the administrator.
  5. After this, you have to activate PPTP VPN Passthrough within ‘Security.’
  6. Now, you must look at the instruction manual of your router to know the steps for setting port forwarding since different companies have different instructions for this process.
  7. Finally, you have to set up and connect the VPN.

If you activate your VPN Passthrough successfully, then you will see a prompt from the system asking to enter your VPN’s username and password.

And, when you enter these details properly, you can browse the web and enjoy the services provided by your VPN client.

Conclusion

Since new VPN software and hardware do not require a VPN Passthrough, the need for the same is quickly declining.

However, if you use outdated VPN devices and protocols that run on old OS, then you would require a VPN Passthrough so that you don’t face any problems while using your VPN.

Moreover, you must know that the VPN services that have old VPN Protocols are free of cost. Since they are free of cost, they do not protect you when you browse the internet.

And, the aim of a VPN is to protect you while browsing online.

This is why you must go for paid VPN clients that provide premium services. They would be a good investment for you in the long term owing to the privacy and security they provide.

Thus, if you use premium VPN clients that use new VPN protocols and devices that run on the latest OS, then you do not have to get a VPN Passthrough. Plus, you can enjoy many great VPN services.

Written by Jason

Hi! I’m the editor at EarthWeb. I have a deep interest in technology and business. I also enjoy testing products out. Contact me to be featured!