Cryptography Guide for VPN Security Online
Written by  Daisie Team
Published on 9 min read


  1. What is Cryptography?
  2. Types of Cryptography used in VPN
  3. How Cryptography Ensures VPN Security
  4. Symmetric vs. Asymmetric Encryption
  5. Hash Functions and VPN Security
  6. Public Key Infrastructure and VPN
  7. Secure Sockets Layer and VPN
  8. How to Choose a Secure VPN Service

If you've ever wondered how your online data stays safe when using a VPN, you're in the right place. This guide will walk you through the exciting world of cryptography in VPN security. In simpler terms, we'll explore how secret codes keep your data protected online. So, buckle up, and let's dive into this virtual journey of online security.

What is Cryptography?

Cryptography is like the secret sauce in your favorite burger - you might not see it, but it's there, doing its job. In the world of online security, cryptography is a method of taking plain data and turning it into something unreadable. It's a bit like writing a secret message, but instead of a note passed in class, it's your personal data being sent over the internet.

Imagine you're sending a postcard to your friend. You wouldn't want anyone who picks up the postcard to read your personal messages, would you? That's where cryptography comes into play. It scrambles your message, making it unreadable to anyone who doesn't have the right tools to decode it. Now, apply that same concept to your online data, and you have the essence of cryptography in VPN security.

Now, let's break down how cryptography works:

  1. Encryption: This is the process of turning your data into the unreadable text we mentioned earlier. It's like turning 'Hello, friend!' into 'H3ll0, fr13nd!'
  2. Decryption: This is the reverse of encryption. It's the process of turning the scrambled text back into its original form. So, 'H3ll0, fr13nd!' becomes 'Hello, friend!' again.
  3. Keys: In cryptography, a key is a piece of information that determines the output of the encryption and decryption. Without the right key, the scrambled text remains a mystery.

So, in a nutshell: cryptography is all about keeping your private data private. It's the superhero of the internet world, protecting your information from prying eyes. And when it comes to cryptography in VPN security, it's even more powerful — but we'll get to that later.

Types of Cryptography used in VPN

Let's think of cryptography in VPN security like different types of locks for doors. Some locks are simpler, like the ones you might find on a bedroom door. Others are more complex, like a bank vault door. The 'lock' you choose depends on what you're trying to secure.

When it comes to VPNs, they use two main types of cryptography to secure your data:

  1. Symmetric Cryptography: This type uses one key for both encryption and decryption. Think of it as having one key to both lock and unlock a door. It's faster and requires less computational power, making it ideal for encrypting large amounts of data.
  2. Asymmetric Cryptography: Here, two different keys are used — one for encryption and another for decryption. It's like having a separate key to lock the door and another to unlock it. It's slower and requires more computational power, but it's more secure because even if someone gets hold of the encryption key, they still can't decrypt your data.

Both these types of cryptography play a vital role in the realm of VPN security. They work together to create a secure tunnel for your data to travel through. It's like having a private highway for your data, with tollbooths at either end that only let your data through.

So, next time you're using a VPN, remember: there's a lot of smart technology working behind the scenes to keep your data safe. It's not just about masking your IP address or accessing geo-restricted content - it's about ensuring that your data remains as private as possible. That's the power of cryptography in VPN security!

How Cryptography Ensures VPN Security

Imagine you're sending a secret message in a bottle across a crowded room. You wouldn't want anyone else to read that message, right? That's where cryptography in VPN security comes into play.

When you use a VPN, your data travels through the internet in packets. Think of these packets as tiny digital messages in bottles. Now, if you just send these packets as they are, anyone can intercept them and read your data. To avoid this, your VPN uses cryptography to transform these packets into unreadable gibberish.

Here's how it works:

  1. Encryption: Before your data leaves your device, the VPN applies a secret code known as encryption. This turns your data into a jumble of characters that can't be understood. It's like turning your message into a secret language that only you and your VPN know.
  2. Transmission: Your encrypted data is then sent through the internet. Even if someone intercepts your data packets during this stage, they won't be able to understand anything. It's like they've found your message in a bottle, but they can't read the secret language.
  3. Decryption: Once your data reaches the VPN server, it's decrypted or translated back into its original form using a secret decryption key. This makes your data readable again. It's like your VPN has opened your message in a bottle and translated the secret language back into English.

This process is repeated every time data is sent from your device to the VPN server and vice versa. This way, cryptography ensures that your data remains private and secure throughout its journey.

So, the next time you use a VPN, remember that there's a whole lot of cryptographic magic happening to keep your data secure. It's not just about changing your IP address—it’s about creating a secure pathway for your data. That's the power of cryptography in VPN security!

Symmetric vs. Asymmetric Encryption

Let's continue our journey into cryptography in VPN security by exploring two popular types of encryption: symmetric and asymmetric. Picture this: you have a box that you want to lock, but you also want a trusted friend to be able to open it. What type of lock would you use?

Symmetric encryption is like having one key that both you and your friend use to open the lock. When you send data over a VPN, this single key is used to both encrypt your data (lock the box) and decrypt it (open the box). This type of encryption is fast and efficient, but there's a catch: if someone else gets a hold of your key, they can open your lock.

On the other hand, asymmetric encryption is like having a pair of keys: one to lock the box, and a different one to unlock it. In the context of VPNs, one key (the public key) is used to encrypt your data, and a different key (the private key) is used to decrypt it. This method is more secure because even if someone gets your public key, they can't decrypt your data. However, this extra security comes at a cost: asymmetric encryption is slower than symmetric encryption.

So how do VPNs choose between these two types of encryption? They don't! Most VPNs use a combination of both: symmetric encryption for speed, and asymmetric encryption for secure key exchange. It's like having the best of both worlds: a lock that's both fast to open and hard to pick. That's yet another example of the role cryptography plays in VPN security.

Hash Functions and VPN Security

Imagine you're baking a pie. You add all your ingredients, mix them together and let it bake. The result is a delicious treat that you can't change back into its separate ingredients. This is essentially how a hash function works in cryptography for VPN security.

The hash function takes your data—let's say it's the recipe for your pie—and churns out a fixed length of scrambled text, this is your baked pie. The beauty of the hash function is that no matter how many times you plug in the same data (or recipe), the scrambled text (or pie) will always be the same. But if you change even one small piece of the data, the hash function will produce a completely different result.

Now, let's bring VPNs into the picture. Remember when we talked about symmetric and asymmetric encryption? Well, hash functions add an extra layer of security. When data is sent through a VPN, the hash function creates a unique 'hash value' for the data. This value is like a digital fingerprint: it's unique to the data, and it ensures that the data hasn't been tampered with during transmission.

Here's the clever part: the receiver of the data can run the same hash function on the data they receive. If the hash value they get matches the one sent with the data, they know the data hasn't been changed. If the values don't match—someone's been messing with your pie!

So, while hash functions might seem like some complicated baking recipe, they're actually a vital part of maintaining data integrity and furthering cryptography in VPN security.

Public Key Infrastructure and VPN

Let's imagine you have a secret message, and you want to send it to your friend. You could use a secret code to scramble the message, but how do you get the code to your friend without anyone else seeing it? This is where Public Key Infrastructure (PKI) comes into play in cryptography for VPN security.

PKI uses a pair of keys—a public key and a private key. The public key is like a lock, and the private key is the only key that can open it. Everyone can have a copy of the public key (the lock), but only you should have the private key (the key).

When you send a message to your friend via a VPN, your friend's public key is used to encrypt or 'lock' the message. Once it's locked, the only way to unlock it is with your friend’s private key. Anybody else who tries to unlock it without the private key will be left scratching their heads.

But it doesn't stop there. The PKI also provides a digital certificate, acting like a digital ID card. It confirms that the public key belongs to the person you meant to send the message to, assuring you that you're not sending your secret message to a stranger.

So, PKI is like giving your friend a locked box with a secret message inside and then mailing them the key in a separate package. Even if someone intercepts the box, they can't open it without the key. This is how PKI adds another level of security, enhancing the role of cryptography in VPN security.

Secure Sockets Layer and VPN

Have you ever noticed that some websites start with 'https' instead of just 'http'? The 's' stands for secure, and it's all thanks to something called Secure Sockets Layer (SSL). This technology is one of the ways cryptography ensures VPN security.

SSL creates an encrypted link between your web browser and the server. Think of it like a secret tunnel that your data travels through, safe from prying eyes. Even if someone manages to intercept your data, they won't be able to understand it because it's all jumbled up.

When you connect to a VPN, SSL makes sure that the connection between your device and the VPN server is secure. It does this by using something called 'handshake protocols.'

Here's a simple way to understand it: imagine you're meeting someone for the first time. You might shake hands, introduce yourselves, and show each other your ID to confirm you're who you say you are. SSL does a similar thing when your device tries to connect to the VPN server. They exchange keys, verify each other's identities, and then establish a secure connection.

Remember, not all that glitters is gold. Always make sure your VPN uses SSL or its updated version TLS (Transport Layer Security), because it's a reliable way to ensure the integrity of your data, and it plays a vital role in cryptography for VPN security.

How to Choose a Secure VPN Service

So, you're ready to take the plunge and start using a VPN. That's a smart move! But how do you choose a secure VPN service? Well, here are a few things to keep in mind.

Firstly, you need to find out what kind of encryption they use. Remember our talk about symmetric and asymmetric encryption? Check if the VPN uses strong encryption methods. If it uses AES-256 (Advanced Encryption Standard with a 256-bit key), then you're onto a winner. This is the same level of encryption used by governments and banks, so you know it's strong.

Next, find out if they use protocols like SSL or TLS. These protocols are like your data's armor during its journey through the internet. They ensure your data arrives safely at its destination without anyone being able to sneak a peek.

Also, consider the VPN's privacy policy. Make sure they don't keep logs of your online activity. After all, the whole point of using a VPN is to protect your privacy, right? So, a no-logs policy is a must.

Lastly, check user reviews and ratings. Nothing beats hearing about real-life experiences from people who've used the service. They can give you insights into the VPN's performance, speed, and reliability. And if you spot a lot of complaints about security issues, it's probably best to steer clear.

With these tips in mind, you're well on your way to choosing a secure VPN service. Remember, the role of cryptography in VPN security is paramount, so make sure your chosen VPN takes it seriously!

If you found this blog post on cryptography and VPN security helpful and want to learn more about the digital economy's backbone, check out Tom Glendinning's workshop, 'Crypto For Creators, Part 1: The Backbone Of The Digital Economy.' This workshop will provide you with valuable insights into the world of cryptography and its applications in the creative industry, helping you better understand and secure your online presence.