What is end-to-end encryption and how does it work?

Online privacy is the need of the hour. Especially when there is a steady increase in the number of methods of capturing user data. However, there is one particular space on the Internet where maximum privacy is needed, and that is messaging apps. Recognizing this need, major Internet messaging services use end-to-end encryption techniques to keep your conversations safe and secure.

But what does that even mean and how does it actually work? Does it really work? Well, we are sure you have all these questions on your mind. Therefore, we have written this article to help you find answers and understand the concept of encryption. Let’s get started.

First, let’s understand what encryption and decryption mean.

Understand the basics of encryption

  • Encryption means converting information into a code that hides the true meaning of the information.
  • Decoding means converting this code to the original information and returning its value. This is a reverse encryption mechanism.

However, to truly understand this, we obviously need more context.

Why do you need encryption?

When you post something online, whether it’s a message, a comment, or a picture, it carries some kind of “information.” That is, if you send me a message, I will be able to interpret the information you are trying to convey. Likewise, if you send me an image, I will be able to see and interpret the content of the image.

We need to understand that this message or image is not valuable in itself, but it is valuable in the information it provides. It is valuable for information that can be interpreted as you see it. What if the message or image you send has been seen online by someone other than me?

They will learn the information you are trying to convey and that is a concern because you only want me to interpret it. So, what about using encryption and decryption? Exactly – and this is where end-to-end encryption comes into play.

What is end-to-end encryption

You encrypt the message/image you are trying to send and it is transmitted over the internet as a “secret” code. And it is done in such a way that only I can decipher this “secret” code. That way, once it reaches me, I can decipher and interpret that information.

However, as mentioned earlier, what matters is the ultimate meaning. In this way, it is possible to transfer the message/image as secret codes from the sender to the receiver. This process is called end-to-end encryption.

In simple terms, end-to-end encryption ensures a secret communication between the sender and the recipient, preventing third parties from gaining access to this information. The tools and technologies that help us carry out this process are built into the messaging apps and other software we (may) use.

Let’s dive into it.

How end-to-end encryption works

We clearly understand the purpose of end-to-end encryption, which is to prevent attackers from stealing information between sender and receiver. Now let’s understand this concept through a situation we used earlier – you send me a message.

When we use an end-to-end encryption service, it gives us a pair of public and private keys. These keys help us in encryption and decryption. Along with this, the messaging app has an algorithm that consists of mathematical functions that need to be solved to either encrypt or decrypt the data.

When you send me a message, you will receive a public key that is tied to my chat. The public key is used to encrypt the message using an algorithm present in the messaging application. This public key will help you recognize my device and what I should receive the message.

Now I will use the private key which helps me to decrypt the message and interpret the information of the message sent by you. This private key is only available for my device. This way, no one else will be able to decrypt the message – so the end-to-end encryption will be successful.

This is the fundamental working principle of end-to-end encryption. However, if you want to learn more, we recommend that you delve into the concepts of cryptography.

However, not all services use end-to-end encryption. Some typically use transport layer encryption instead. So, let’s look at the difference between the two.

End-to-end encryption vs. transport layer security encryption

As mentioned earlier, not all services have end-to-end encryption. But that doesn’t mean they don’t have encryption tools at all. The most common form of encryption for websites is TLS – Transport Layer Security encryption.

The only difference between this and the final one is that in TLS the encryption happens on the sender’s device and is decrypted on the server. So it’s not really end-to-end encryption, but it does provide a good degree of security and protection for your information.

Illustration of TSL – where decryption happens on the server, at the final stage.

It is also called encryption in transit. This means that the service provider can access all your messages through their servers. That’s why you can easily see your old messages on Instagram when you just download the app, but not on WhatsApp. You can restore the messages only by downloading the backup file and decrypting it on your device.

Now that we have a clear idea about end-to-end encryption, let’s learn about the main advantages and disadvantages.

Advantages and disadvantages of end-to-end encryption

Here are some of the benefits of end-to-end encryption.

  • Every step of the way is fully protected.
  • Messages and related information cannot be accessed by messaging service servers.
  • Unauthorized people on the Internet cannot access the information.
  • You cannot restore messages through a new login – unless there is an encrypted backup. Consider the example of Instagram Messenger and WhatsApp Messenger described above.

Here are some disadvantages of end-to-end encryption.

  • Metadata such as date, time, and participant names are not encrypted.
  • If the endpoints (sender or receiver) are vulnerable to attack, end-to-end encryption can do little.
  • In some cases, a man-in-the-middle attack is possible despite end-to-end encryption. Therefore, if someone decides to impersonate the sender or recipient physically, the messages and information can be read by unintended people.

So those were all the pros and cons of end-to-end encryption. If you’re still wondering whether you should enable end-to-end encryption even if you’re not sending secret messages, the answer is a resounding YES. Why let others access your data at all?

So, if you plan to use this service, the following section details which popular messaging services provide end-to-end encryption.

Popular messaging apps with end-to-end encryption

Here are some of the best messaging apps with end-to-end encryption for iPhone and Android. You can use any of the following to add a layer of security to your messages.

1. WhatsApp Messenger

The ever so popular messenger WhatsApp supports end-to-end encryption. You can use the links below to download and install for both iPhone and Android.

2. Signal Private Messenger

Signal is another all-in-one messenger for iPhone and Android with end-to-end encryption. We believe it provides a more modern user interface compared to WhatsApp.

3. iMessage

iMessage as we all know is the vanilla messaging app for all Apple users. All messages and files in iMessage are end-to-end encrypted. However, it is not cross-platform and thus not available for Android.

4. Telegram

Telegram is another multi-purpose messenger that we all want to use as our primary messaging app and want all WhatsApp users to switch to it. It offers end-to-end encryption, albeit on an add-on basis. This option is called “secret chat”.

These are all popular apps we can recommend for private encrypted messaging. And with that, we’ve written everything you need to know about end-to-end encryption. If you have more questions, check out our FAQ section below.

Frequently asked questions about end-to-end encryption

1. Does Instagram Messenger have end-to-end encryption?

No, both Instagram and Facebook Messenger do not have end-to-end encryption.

2. Does the Internet connection require end-to-end encryption?

Yes, the end-to-end encryption service requires an Internet connection.

3. Is Gmail end-to-end encrypted?

No, Gmail does not have end-to-end encryption. If you want an encrypted email service, you can check out Proton Mail.

4. What is the difference between a private key and a public key?

Public keys can only be used to encrypt data, while private keys can be used for both encryption and decryption.

5. How can you tell your data is encrypted?

You will only be able to access the encrypted data on one specific device and no one else will be able to access it. So this is one way to check if your data is actually encrypted. What’s more, the app or service that provides encryption also tells you when your data and files are encrypted.

Keep your messaging private with end-to-end encryption

That’s all you need to know about end-to-end encryption. We hope you found this article easy to understand. Now, the next time you see a banner that says “your messages are end-to-end encrypted” – you know what it means!