WEBVTT

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Now what does encrypting actually mean in general.

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You could say make data unreadable for thought parties only specific people or entities are allowed

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to read this data.

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I also include entities because we are maybe not talking about people but machine to machine communication

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to make the data readable again.

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We use decryption the decryption can take place just in memory take a password manager as an example

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passwords only decrypted for a short amount of time and not permanently or a decryption could be permanently.

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For instance when you decrypt a file archive encrypting takes place on the basis of secret cryptographic

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keys.

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Technically speaking in the ideal case a plain text so unencrypted data becomes seemingly pure random

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data which can only become readable again using the correct cryptographic key random data means in fact

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random numbers are stored in binary form.

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Hence through unauthorized access.

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Nobody can tell anything about content or structure of the original data.

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To get a better feeling for what encryption actually means.

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On the technical level I want to demonstrate a file encryption.

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I will now use the open source tool crock of crap file to encrypt a simple plain text file the text

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file is called license.

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I will open it quickly in a normal text editor.

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As you can see it is a simple text file containing a couple of paragraphs.

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And this I will encrypt.

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Now

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I use a simple paste based encryption.

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I am also using a very simple password but that is not important here.

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And now we have here the encrypted file which is also called license.

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I will now also open this file within the text editor.

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Compared to the original file the simple plaintext file became a binary file all the different black

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characters these special characters are Eskies special and command characters.

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The editor I am using is able to display these.

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The result of binary analysis would be that this file contains only random numbers which are stored

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in binary format as you can see from this binary data.

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You cannot tell anything about the structure nor content of the original plain text file.

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This is exactly the purpose of encryption.
