Don't want your messages to be read by the server responsible for transferring them between you and the recipient?
In that case, end-to-end encryption (or end-to-end encryption, abbreviated as E2EE) is the necessary solution for you.
End-to-end encryption is a method of encrypting communications between the recipient and the sender so that they are the only party that can decrypt the data. Its origins can be traced back to the 1990s, when Phil Zimmerman released the encryption program Pretty Good Privacy (also known as PGP).
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How do unencrypted messages work?
Let's talk about what a typical messaging platform looks like on a smartphone. You install the App and create an account. The App allows you to communicate with people who do the same. You write the message, enter the username, then post it to the central server. The server knows that you sent a message to your friend, so it delivers the message to its destination.
This is the client-server model. The client (your phone) doesn't do much – instead, the server does all the heavy lifting. But it also means that the service provider is the middleman between you and the recipient.
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Most of the time, the data between A <span S and S <span B in the diagram is encrypted. One example is Transport Layer Security (TLS), which is commonly used to secure connections between clients and servers.
TLS and similar security solutions prevent anyone from intercepting mail as it is moving from the client to the server. Although these measures can prevent outsiders from accessing the data, it can still be read by the server. This is where encryption techniques come into play. If data from A has been encrypted with a cryptographic key that belongs to B, the server cannot read or access it.
Without E2EE methods, the server could store information in a database along with the information of millions of others. As large-scale data breaches have occurred time and time again, this can have disastrous consequences for end users.
