"A solution would be to know which is a computer and which is a real user, it's not impossible to do so."
It seems like you have revolutionary knowledge that could change the course of human history. Or you're just trolling. Since you are not pointing to any actual approaches and hundreds of thousands of engineers have not yet come up with what to you is just "a solution" that doesn't even require further specification, I will go with trolling.
Figuring out remotely whether you are dealing with "a human" without any interaction (or, particularly, interaction less than a captcha, or even -gasp!- a two word captcha) is very definitely impossible. Think about it - how do you know whether it's a human? Well, you say, the black box device that he is sitting at has made sure that he is! And how does that machine transmit data to you? Over that data line that this supposed human is sitting right next... I guess you will see where I'm going with this.
It seems like you have revolutionary knowledge that could change the course of human history. Or you're just trolling. Since you are not pointing to any actual approaches and hundreds of thousands of engineers have not yet come up with what to you is just "a solution" that doesn't even require further specification, I will go with trolling.
Figuring out remotely whether you are dealing with "a human" without any interaction (or, particularly, interaction less than a captcha, or even -gasp!- a two word captcha) is very definitely impossible. Think about it - how do you know whether it's a human? Well, you say, the black box device that he is sitting at has made sure that he is! And how does that machine transmit data to you? Over that data line that this supposed human is sitting right next... I guess you will see where I'm going with this.