If you approach the question so simply "it can't be", it's hard to say. Assuming that it is possible, I can describe the essence of the idea. Let's imagine that we need to encrypt and pass one byte octet, which is 8 bits. Agree that if we can encrypt one byte without a key, we will probably be able to encrypt the other. If this level of discussion suits you, then you can play logic games and try to explain the essence of this method to you.  Let's agree again on the terms. If we use a key, we choose an encryption scheme in the encryption system. You don't know the key yet - you just don't know what algorithms to use to work with the code (either to encrypt it or to decrypt it). Is there a disagreement on this point?

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If you agree with that, we'll continue. In modern cryptography (let's talk about symmetrical one so far), astronomical numbers and Calculus are usually used. There are known problems, but in general it is a great achievement of human thought. These are the key-type systems. The key is the rules of encryption and deciphering. In the keyless symmetric system, there are also encryption and deciphering rules. There is no difference in the principles of operation, the only difference is the absence of a key itself. Now, what is a key, as we understand it, what is its function? It's some kind of digital code that the user keeps secret, which should be exactly the same for another user (we're talking about symmetric systems, like the EE2E, often based on AES for encrypting information and an asymmetric system for generating the initial keys). If this information disappears, your communication is either tapped or modified. In a keyless system, there is an encryption scheme, but no stored and used key information. The question was asked correctly - this encryption scheme will be calculated very quickly. That's right. To protect against such simple hacking move, a keyless system uses a constant change of system, as often as possible. It is possible to do this on a single packet of transmitted information. Minimum packet size is 304 bits. This means that it is harder to find a rule to convert such a packet by brute force than in AES with a 256 bit key. Let's stop here and take a look at the comments. I said less that one percent of the information about the keyless deviceso far, consider that this is only the beginning (and already there is so much text).

It's unusual to understand. But it is possible to arrange everything in a logical order. First, you have your encryption settings, let's call them initial, initial settings. Then you want to connect to your partner. It is important that the partner has the same encryption settings as the partner. Well, if you are more accustomed to other words, let it be one key, the same for two. Agree that in one encryption system, the key creates specific system settings, the key selects the encryption scheme. But in a normal key system (a double ratchet will be discussed later), the logic of the process is as follows: the system takes your information, takes your key, and creates a cipher. In a keyless system there are other processes going on. The system takes your information with the initial settings - it generates a cipher. But the trick is that the next information will be encrypted in a completely different way, as you used to - under a different key, the scheme itself will be chosen by the system based on many factors, and the external observer can not see them and can not calculate. This is a big topic, we can talk, but we need to be clear that there are no logical contradictions in this idea. Moreover, unlike the key system, the information itself is not encrypted. There is one method that is used, it is a method of temporary correspondence of your information - the internal element of the system. But this element will not be encrypted either. Only a temporary link to this element will be encrypted. Then the cipher will be a digital description of the link. Then, it is logical to assume that deciphering the link itself, to an external observer who does not know the initial settings of the system - without meaning, as well as without meaning to decipher the link to the Internet, link. You have to go and see what this link points to. So this system works.

Maybe the answer is in a different cryptography. In keyless cryptography, in a system from which it is not possible to steal keys or passwords. I know that such developments are now in progress. Yes, they are probably very closely related to passwordless authentication. With one that never uses biometric data. The question remains what such authentication uses. And there is an answer - a variable numeric identifier. The beauty of this idea is that if you have a password or a key, your identifiers are numeric but seemingly permanent. The new technology proposes to make variable identifiers. So much variable that it is impossible for an outside observer to catch or predict the next identifier. And its changes are so rapid that stealing the current one is also useless. Here is the real way to a new cryptography and to a new level of security for the user. Probably, the keyless and passwordless system, is an only possible answer for the ordinary user today, in the world of quantum computers and quantum calculations.

Maybe the answer is in a different cryptography. In keyless cryptography, in a system from which it is not possible to steal keys or passwords. I know that such developments are now in progress. Yes, they are probably very closely related to passwordless authentication. With one that never uses biometric data. The question remains what such authentication uses. And there is an answer - a variable numeric identifier. The beauty of this idea is that if you have a password or a key, your identifiers are numeric but seemingly permanent. The new technology proposes to make variable identifiers. So much variable that it is impossible for an outside observer to catch or predict the next identifier. And its changes are so rapid that stealing the current one is also useless. Here is the real way to a new cryptography and to a new level of security for the user. Probably, the keyless and passwordless system, is an only possible answer for the ordinary user today, in the world of quantum computers and quantum calculations.