What is end-to-end encryption? How does end-to-end encryption keep communications private? I will explain so that even non-experts can understand.
In recent years, various communication services have announced implementations of end-to-end encryption, from WhatsApp to Zoom.
“End-to-end encryption”—you might have thought it was a term you saw a lot these days. “Encryption” means transforming data so that it is unreadable. So what is “end-to-end”? What can end-to-end encryption do and what it can’t do?
Now, let’s try to explain it as simply as possible without going into the mathematics that is the basis of encryption and relying on technical terms as much as possible.
What is end-to-end encryption and what other communication methods are there?
End-to-end encryption is the practice of encrypting a message on one device (e.g. a smartphone or PC) and ensuring that it can only be decrypted on the device to which it is sent. From the time it leaves the sender to the time it reaches the recipient (this is called “end-to-end”), the message remains encrypted.
What other methods of communication are there? First, there is a way to send the message in plain text (i.e. without encryption). This is the least secure method. For example, data sent by SMS (short message) is not encrypted and can theoretically be intercepted by anyone. Luckily, it’s practically impossible to intercept without special equipment, which limits the number of people who can snoop on your text messages to some extent.
There is also a way to encrypt messages in transit. Messages are encrypted by the sender, sent to the server, decrypted on the server, encrypted again, and delivered to the recipient, where they are decrypted. This method protects the information in transit, but allows the intermediary server to know the contents of the message. Problems can arise if the person or entity that owns the server is unreliable.
A method that encrypts data during transmission also has the advantage that it can be used for purposes other than just sending data because it communicates through a server. For example, you can store message history on our servers, add participants to conversations using alternate communication channels (such as joining a video conference by phone), and take advantage of automatic moderation.
This method is also a solution to the primary problem of data being intercepted and read as it travels from user to server and server to user. This is the most easily intercepted point in the message transmission chain, but if the intercepted message is encrypted, it cannot be read. For that reason, there are many services that adopt this method regardless of end-to-end encryption. For those who value convenience and access to additional services over increased data security, this may be a better choice.
What end-to-end encryption protects
The main advantage of end-to-end encryption is that only the recipient can see the data being sent. It’s like sending a letter in a physically unopenable box that cannot be opened with a sledgehammer, saw, or pick, but only by the recipient. End-to-end encryption keeps your communications confidential.
Creating a box that can never be opened is impossible in the real world, but possible in the information world. Mathematicians are constantly working on developing new cryptographic systems and improving the strength of old ones.
Another advantage is that the message cannot be decrypted by anyone other than the recipient. Therefore no one can change the message. With modern encryption methods, if someone modifies the encrypted data, the decrypted message will be garbled, making it immediately obvious that someone has messed with it. The inability to make predictable changes to encrypted messages means that the text cannot be changed.
In this way, communication consistency is guaranteed. If you receive a successfully decrypted message, it is identical to what the sender wrote and was not tampered with during transmission (in fact, messenger apps automatically do this for you). functioning like this).
What end-to-end encryption cannot protect
After seeing the benefits of end-to-end encryption, you may feel that this is the way to solve all your information communication problems. But no… end-to-end encryption has its limits.
First, with end-to-end encryption, no one can see the content of your message, but the fact that you sent a message to (or received a message from) a specific person is clear. Servers can’t read your messages, but they know for sure that you exchanged messages at a particular time on a particular day. The mere fact that you are interacting with a particular person can draw unwanted attention.
Second, if the device you’re using to communicate falls into someone else’s hands, they can read all your messages, and they can even write and send messages pretending to be you. Therefore, if you secure your communications with end-to-end encryption, you should also protect your device and apps. At least set a PIN number. That way, if your device is lost or stolen, it will help prevent others from knowing what you exchanged or being the victim of identity theft.
However, if your smartphone is infected with malware, your messages can be read in the same way that someone would physically hold your smartphone. No matter what kind of encryption you use, the danger is the same. For these reasons, you should keep your device protected with security software.
Finally, even if all your devices are fully protected and no one can access the messages stored on them, you still have no way of knowing what the device you are talking to is doing. End-to-end encryption, too, can’t do anything about it.
Despite these limitations, end-to-end encryption is still the most secure way to transmit sensitive data, and more and more telecommunications services are adopting end-to-end encryption.