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Now that we understand how Ppgpp works.

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In this lecture and the next few lectures, I'm going to show you how to use it to encrypt all kinds

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of data, verify integrity, and so on.

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Now, as I explained in the previous lecture, for this to work, the receiver, which is John in this

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case, has to first generate a key pair, a public key and a private key.

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He will share the public key with the person who he wants to receive data from.

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That person who is David in this example will use the public key to encrypt the message.

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Send the message to John.

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The message will be unreadable unless the private key is used to decrypt it.

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And as you can see throughout this whole scenario, the private key never left John.

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So John never shares the private key.

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And it is the only key that can be used to decrypt the data.

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Therefore, this implementation is very, very secure.

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So like I said, the first step for this is the receiver needs to generate a key pair.

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A public key and a private key.

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So in this lecture, I'm going to show you how we can create our own key pair so that we can share our

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public key with the people that we want to receive data from.

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And then they can use this public key to encrypt data and send it to us so that we are the only ones

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that can decrypt this data because we have the private key.

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So we can do this in tales easily using a pre-installed program called Cleopatra.

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You can find this program in the applications under accessories, and we have it right here.

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Now, you actually would have used this program already if you installed the Tor browser on Windows.

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But anyway, we have a different use case in here and the goal is to actually use it to create a key

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pair for us.

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Now, as you can see by default it has a number of keys already installed on it.

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Now these keys are pre-installed by the developers.

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You can see the names of these keys, the emails associated with them, the dates from which they're

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valid and until when they expire.

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And the key ID.

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Now it's very important to understand that you should never delete any of these keys because these keys

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are actually used to validate the integrity of packages that tales downloads.

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So whenever you're installing updates or if you're installing programs on tales, these keys are used

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to validate that these packages or these updates are not getting modified as they're being downloaded

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from their original sources.

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So it's very important to keep these keys the same.

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What we want to do right now is to create our own key.

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And to do that, we're going to click on file and click on New key Pair.

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We're going to select the first option in here to generate a personal openpgp key pair.

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And it's asking us for the name and the email.

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As you can see, these values are optional.

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You don't actually have to put anything in here.

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It is very important to keep in mind that the values that you put in here will be visible to anybody

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that you share the key with.

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So if you're sharing it in the future with people that you are not sure you should trust, then you

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want to make sure that you use the fake name and fake ID and your private or anonymous email that we

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created earlier, or you can simply just leave it blank.

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So I'm going to just put the name as John Wick and my private and anonymous email is J and seven at

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illudin.

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And I'm going to click on the advanced Options to show you what we can change and give you an idea of

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what else can be modified.

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So you can see in here the encryption or the key type is set to RSA.

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You want to keep this the same.

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This is a very strong encryption.

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We're just going to increase its value to 4096 bits.

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And in here in the certificate usage, you can tick the boxes that you're going to use this key for.

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So as you can see right now, the key is going to be used for signing for encryption and certification.

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And we're not going to be using that key for authentication.

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That is completely fine.

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We actually only want to use it for signing encryption and certification.

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So we're going to keep all of these options the same.

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And you can also set an expiry date for this key so that it expires once it reaches the date that you

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select here, you can untick this box to keep it valid forever or just keep it ticked and set an appropriate

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date.

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Once you're happy with the options we're going to click on.

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Okay.

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And we're going to click on next to go to the next step.

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As you can see, it's showing us a summary of the values, the details that we filled.

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And you can click here to show all details, to see all of the options and the values that we selected.

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We're happy with everything.

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So we're going to click, Create, and finally, it's going to ask us to set a passphrase for this key.

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Make sure you choose a strong passphrase that is hard to brute force or to guess.

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And we're going to click on okay to finish this process.

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And perfect.

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The key is created.

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Now we have the fingerprint as well.

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We spoke about this previously when we were talking about validation and we will actually talk about

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it in more details in the next lectures.

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We'll also talk about these next steps in the next lectures.

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Anyway, so we're happy with what we did so far.

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We're simply going to click Finish and as you can see, we have the new key in here at the bottom in

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bold.

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Now this key is in bold because it actually contains two keys.

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It contains a private key and a public key.

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The public key is the one that you share with the people that you want to share encrypted data with.

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And the private one is the one that you keep yourself and you never share it.

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All of the other keys in here are not in bold because they are public keys.

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They do not contain the private key because these are actually not our own keys.

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Therefore, the creators of tales have shared their public key in here so that we can validate the packages

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downloaded are actually made by them.

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But these entries do not contain the private key, obviously, because the tales developers keep these

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private keys for themselves and use them to sign the packages that they distribute to us.

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Now, you can also get more details about any of these keys by simply right clicking the key and going

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to the details in here at the bottom.

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So as you can see, we can see the email, the name, We could see this anyway at the start.

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You can also see the dates from which it's valid.

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And when it expires, you can see the type, you can see the fingerprint.

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And like I said, this is useful for data validation, but we'll talk about that in more details later.

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You can even change the passphrase from here and the more details in here, obviously give us even more

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details and we'll talk more about exporting the keys and sharing them and sharing the certificates in

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the next lectures.

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But for now, we have our key created and stored inside this program, Cleopatra.

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And in the future, I'm going to show you how to use this program and use this key to encrypt text and

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share information privately.