What is VPN and How It Works?

As a cyber security engineer, knowing about and working with VPNs is bread and butter. Which brings us to the question, “What is a VPN?

A VPN is short for virtual private network. It's like a secret hiding space on the internet that helps keep your online activities private.

When you use a VPN in computer network, it takes your internet data and scrambles it up, making it hard for others to understand what you're doing. This encryption renders your online activities unintelligible to entities like your ISP or government authorities. Being connected to a VPN ensures that your online actions remain private and secure, shielded from potential monitoring or surveillance

In this Virtual Private Network tutorial, I’ll take you through the functions, types, and pros and cons of using a VPN in a computer network.

How Does a VPN Work?

Imagine sending a postcard via the mail, where anybody who handles it may read the writing on it. However, the message will only be visible to you and the person holding the key if you place that postcard inside a locked box. And a VPN protects your online data in just that way.

The VPN also makes it seem like you're using the internet from somewhere else. Let's say you're in New York and you connect to a VPN server in New Jersey. To websites, it looks like you're browsing from New Jersey, not New York.

This helps you stay private online. It can also help you see websites or watch videos that you couldn't see in your home country because they're blocked or not available.

What Is VPN Tunneling?

The method to secure your device's connection to a VPN server is called VPN tunneling. A regular internet server that has been set up with VPN software is called a VPN server. All data is divided into packets before being transmitted over the internet.

Encapsulation lies at the heart of VPN tunneling. With a VPN, the original data packet is encrypted and protected from surveillance by an outside packet, or protocol.

What Are VPN Protocols?

Usually, VPN apps will give you at least two or three protocols to choose from. Before we talk about each one, let's also answer the question, what is a VPN protocol?

A VPN protocol is essentially a collection of protocols that enable your devices to connect to a private network.

Every VPN protocol interacts with the VPN network using a unique collection of processes, rules, and programs. However, different protocols handle it in different ways, which is why each has advantages and disadvantages.

Let’s take a look at the different types of VPN on offer:

1. OpenVPN

Let's start with the gold standard of VPN protocols. OpenVPN. Why is it the standard? Well, that is because of its support and the fact that it is open source. OpenVPN has been available since 2001 and it works on pretty much everything, including Androids, Windows, Linux, Apple devices, and more.

OpenVPN is extensively supported by several router manufacturers as well; some models even come pre-configured with it.

As a result of its extremely secure data transport mechanism, OpenVPN has significant limitations despite being wonderful, secure, and having amazing compatibility for a wide range of devices.

In terms of speed, OpenVPN isn't bad, but it wouldn't be my first option if I were in an encrypted internet speed race.

2. IKEv2

IKEv2 is an improvement on the IKE protocol that was originally released in 1998. This is a great protocol. It's secure, very stable, and surprisingly fast.

Generally, in my own testing, I found IKEv2 to be around slightly less secure than OpenVPN. So, does it have any drawbacks? Well, for one, IKEv2 isn't supported by many router manufacturers and those who do support it require you to have a science engineering degree to set it up.

3. WireGuard

If OpenVPN and IKEv2 were comparable to exquisite four-door sedans, WireGuard would be a high-performance sports vehicle with a V12 engine. In 2020, WireGuard began to show up in VPN apps, offering blazingly quick speeds.

The way WireGuard is built is what accounts for all of this speed. It is incredibly lightweight and open-source. Additionally, it is more technologically advanced than OpenVPN, and it allows you to use your brand-new phone or computer to its fullest potential.

Excellent compatibility with all main systems is another feature of WireGuard. Additionally, a lot of routers began integrating WireGuard into their firmware.

So which protocol should you use?

What are the best types of VPN protocols? Well, it depends.

Elements like, your internet service provider, the device you're using, your configurations, and others can affect VPN performance and stability. So, for you, much like me, WireGuard might be the perfect protocol. But for someone else, IKEv2 or OpenVPN might be the better option.

Types of VPNs

Though we have referred to VPNs as a whole so far in this tutorial, there are many different types. The three most common types of VPN are:

Client-Based VPNs

When most people hear the term "VPN," they think of client-based VPNs. By using a browser extension, app, or desktop software, these VPNs build a private network surrounding a single user and a remote network.

The most well-known client-based VPN service providers are ExpressVPN, StrongVPN, and NordVPN.

Site-to-Site VPNs

Site-to-site Local Access Networks (LANs) are surrounded by protected bubbles created by VPNs that are only available by other (authorized) networks. Large companies with multiple branches that require access to each other's intranets are the ones that use these VPNs the most.

You can connect several intranets to a single Wide Area Network (WAN) via a site-to-site VPN.

SSL VPNs

SSL VPNs are frequently used by companies that have mobile employees to allow employees to access their work internet remotely from home or when they are not in the office.

With the help of these VPNs, users can access their work network from private devices as well, shielding both the employee's device and the company network from harmful actors.

Pros and Cons of Using a VPN

As a cyber security engineer, I cannot help but overstate the importance of VPN in cyber security, as when it comes to protecting myself on the internet, VPNs make the experience tenfold better.

But what’s amazing to me might not be something that you find attractive, so let’s take a look at the pros and cons of VPNs to see if they’re worth it or not:

Pros

• Increased privacy and security

When you're using a VPN, it will encrypt all of your traffic, which makes it harder for anyone to spy on your online activities, steal sensitive data, or hack into your accounts, especially if you're using public Wi-Fi.

• Access to restricted content

Let's imagine that certain content is just blocked from your network because you live in a country with restrictions. You can access websites and services that might not be available in your country by connecting to an encrypted Virtual Private Network (VPN) server.

• Improved anonymity

VPNs provide more anonymity since you can mask your IP address and route your traffic through a VPN server, making it more difficult for services and websites to monitor your online activities.

Cons

• Reduced speed

One drawback of using a VPN is that it can slow down your internet speed when it encrypts and routes it through a server that is located far away.

• Configuration and compatibility issues

Compatibility and configuration are another drawback since setting up a VPN can be difficult, particularly for non-technical people. Some devices may not support VPN functionality and will need you to install the VPN on your router. This in turn requires that your router be VPN-compatible, and so on.

• Potential legal issues

Last but not least is, well, potential legal issues, there could be legal issues. Depending on your nation's laws, using a VPN might be illegal and result in fines, particularly if you use it for illegal purposes.

Wrapping Up

I hope by this point I’ve answered your “What is a VPN?” question. VPNs play a crucial role in ensuring online security and privacy, especially in today's digital landscape where data protection is paramount. 

With the increasing threats of data breaches and surveillance, VPNs provide a layer of encryption and anonymity that helps users safeguard their sensitive information and browsing activities. Individuals and organizations need to understand how VPNs work and how they can benefit from using them. Exploring courses like those offered by upGrad can definitely deepen one's knowledge and skills in this area. 

Frequently Asked Questions

1. How does using a VPN enhance cybersecurity?

The importance of VPN in cyber security cannot be understated. VPNs help create a secure tunnel between your computer in the VPN server, hiding your online location and activity.

2. Are VPNs safe?

Using a VPN in computer network is generally safe since VPN connections are made through highly secure protocols with the best encryption mechanics.

3. Can using a VPN bypass all security risks?

VPNs only offer a way to connect to the internet with anonymity, they are not designed to bypass cyber threats, viruses, or malware.

4. Are VPNs legal to use?

VPNs are legal to use, but using VPNs to commit criminal acts or visit government-banned websites is illegal.

5. Which VPN type is best?

If you’re struggling with how to choose a VPN, my recommendation would be to use the Wireguard type because of its fast speed and stability. If you want something else, you can opt for an OpenVPN or IKEv VPN type.

6. How to test if a VPN is working?

You can visit websites such as IPLocation or WhatIsMyIP to check your IP address, if your VPN is working you should see a different location and IP address.

7. Are VPN free?

Yes, there are free VPN services available, but they often come with limitations or drawbacks compared to paid options.

8. Can I install VPN for free?

You can install a VPN in computer network for free, but the VPN will only offer limited features.

9. Can a VPN be hacked?

VPN services can be hacked, but it is extremely difficult to do so because of the protection behind the VPN services, however, in some cases, smaller VPN providers can be targeted for their vulnerabilities.

10. Do hackers use VPN?

Hackers frequently use VPNs to mask their location and IP addresses.