Where in the Network Should a VPN Gateway Reside?

A VPN (Virtual Private Network) is a popular tool used by private individuals, businesses, and even some large organizations. A VPN allows users to create a private network connection across a public network, such as the Internet or a corporate network, that masks their true IP address and provides them with a secure connection to authorized computers or mobile devices. The VPN connection is secured by default and requires no special setup or configuration on either end.

VPNs allow users to setup a secure connection between two points that would be otherwise unreachable. In the event that one of the devices is accessed by a third party, the VPN can be configured to require a username and password prior to establishing a network connection. This password-protected VPN connection can then be secured with a strong encryption key such as IPSec or SSL.

The most basic use-cases for a VPN involve connecting two points locally, such as a Private Laptop to a Private Server or vice versa. However, modern VPNs can provide much more, such as enabling users to connect to remote sites via a Secure Shell (SSH) tunnel, hiding their IP address, allowing for untrusted networks, and more.

In this guide, we will discuss the various advantages and disadvantages of having a VPN located at different points in your network architecture. Specifically, we will explore the use of VPNs within a DMZ (Demilitarized/Zone-less) and examine the various options for securing VPNs.

VPNs Within a DMZ

A DMZ (Demilitarized/Zone-less) is a layer of security that separates your internal network from the rest of the internet, allowing you to block unauthorized access while still having internet-connected devices within your network. The concept of a DMZ is to provide you with an additional layer of security to prevent attacks from the outside, whether those are from hackers, foreign intelligence agencies, or internet giants like Facebook or Google that may have corporate interests that conflict with your own.

As the name implies, a DMZ does not have any “zones” (areas of security) within it. A DMZ is typically a portion of a network that is physically disconnected from the rest of the network and shares a physical connection with the internet. This allows network traffic to pass through unimpeded, as there are no firewalls or other security devices within the DMZ that would otherwise impede or block the traffic.

The benefit of having a DMZ is that it provides one more layer of security between your internal network and the internet. While this may seem like an advantage, it also makes the network more accessible to potential hackers or other unauthorized users who may be trying to gain access to your network.

There are typically three types of VPNs that work within a DMZ: clientless, client-based, and hybrid.

Clientless VPNs

A clientless VPN is a type of VPN that exists solely within your DMZ, connecting two or more untrusted devices (computers, tablets, or mobile phones) to provide secure and private interconnection. While your own devices are connected, all network activities are not necessarily secured. That is, a clientless VPN does not require any special setup or configuration on the part of the user, as the VPN itself is responsible for securing all traffic.

The disadvantage to a clientless VPN is that without a server to secure and terminate the VPN connection, all network traffic remains vulnerable to interception by outsiders. Therefore, a clientless VPN lacks the functionality of a traditional VPN. However, as mentioned before, this security risk is eliminated if you have a dedicated DMZ and its own VPN server.

Client-Based VPNs

A client-based VPN is a type of VPN that requires at least one trusted device to be present within your network. This device, referred to as a “client,” provides the security for the entire network. As long as the client is able to connect to the VPN and transmit VPN credentials (username, password, and encryption keys) to the server, network activities are completely secure. The client-based VPN can be set up in a similar fashion to a traditional VPN, with a server located on the internal network and connected via a virtual private connection (VPC) or PPTP over a secure channel on the internet. Once the VPN credentials are received by the server, all network activity is secured by default.

The advantage of using a client-based VPN is that it provides a dedicated point of security and reduces the risks of eavesdropping as compared to a clientless VPN. Furthermore, the existence of a trusted device within the network provides the opportunity for the network to be monitored and accessed by authorized individuals. For example, network activity can be monitored and recorded by IT administrators and law enforcement agencies to ensure that the network is operated according to standards and protocols.

Hybrid VPNs

A hybrid VPN is a type of VPN that combines the security of a clientless VPN with the functionality of a client-based VPN. This type of VPN requires at least one trusted device within the network — the “gateway” — which terminates the VPN connection and acts as a secure relay between two other untrusted devices. Thus, a hybrid VPN has the security of a clientless VPN (no network activity is ever exposed or vulnerable) along with the functionality of a client-based VPN (secure and private network interconnection).

The gateway device in a hybrid VPN is usually a server that is physically located within your network and has a public IP address. This server connects to the internet via a secure channel (such as a VPN or SSL connection) and receives data from clients that are also connected to the internet via a secure channel. Once the gateway receives the data, it encrypts it and transmits the encrypted data over the secure channel to the other clients. To prevent the data from being intercepted by outsiders, all network traffic is encrypted as it passes through the gateway server.

The advantage of using a hybrid VPN is that it provides a dedicated point of security within the network while also enabling users to connect to remote sites securely. Furthermore, the ability to connect to remote sites via a secured tunnel creates a greater degree of trust when compared to a standard VPN connection. Thus, a hybrid VPN has the benefits of both a traditional VPN and a DMZ without any of the risks and exposure that come with a DMZ.

Use Cases For A VPN

Now that you are familiar with the various types of VPNs and their use-cases, let’s examine some of the more common ones.

The most basic use-cases for a VPN involve connecting two points locally, such as a Private Laptop to a Private Server or vice versa. However, modern VPNs can provide much more, such as enabling users to connect to remote sites via a Secure Shell (SSH) tunnel, hiding their IP address, allowing for untrusted networks, and more.

Here are some of the more common use-cases for VPNs:

VPN for Sensitive Data

One of the most common reasons for having a VPN is to protect sensitive data. For example, if you are a financial institution that handles payments and other sensitive transactions online, you may want to use a VPN to prevent any unauthorized access to your network and the data stored within it. Similarly, if you are a manufacturer that exports sensitive information such as manufacturing specs or customer contact details, implementing a VPN may provide additional protection against hacking and industrial espionage. Finally, if you are a business that offers a specialized product or service and don’t want your customers to know about your proprietary operations, implementing a VPN may be the answer.

In these three examples, having a VPN server that is physically located within your network (either at the same location as your other servers or in a remote data center) is a common approach. However, this does not have to be the case. At least one device within your network — either a client or a gateway — must be trusted. That is, this device must hold the encryption keys for the VPN, and the user must trust that this device will not be compromised. This way, all network activities are at least as secure as if the VPN server itself was located within your network and was able to protect all traffic as it passed through. Furthermore, if you want to be especially careful, you can have the VPN server and gateway communicate over a secured connection (such as an SSH tunnel) even when they are in different data centers to ensure that no one else can access or tamper with the data being transmitted back and forth. This way, even if your internet connection is compromised, the data being transferred between the server and gateway is still secure.

Similar Posts