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Now that we understand how PDP works in this lecture and the next few lectures I'm gonna show you how

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to use it to encrypt all kinds 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 case

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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 that person who is David.

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And this example will use the public key to encrypt the message send the message to John.

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

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And as you can see throughout this whole scenario the private key never left John so John never shares

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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 so like I said the first step for this is the receiver

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needs to generate a keeper 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 keeper so that we can share our public

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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 so entails.

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This is actually very very easy.

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You can do it using the clipboard applet that we have in here on the top right.

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So you can click on it and go to manage keys.

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Now in the recent versions of tales they've been moving this all over the place.

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So if you can't find it here we can go to applications utilities and click on passwords and keys.

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This will open a program that can be used to manage all your passwords entails.

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But what we're interested in is managing our g new P G keys now clicking on this as you can see we have

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a number of entries by default.

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Do not delete these entries.

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These are actually keys used to verify the integrity of updates that tells downloads and the integrity

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of packages that you can download through tables and install on your system.

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So if you delete them you won't be able to verify the integrity of these packages.

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So we're keeping everything here the same.

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And what we want to do like I said is create our own keeper so we can share our public key with others

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so we can receive encrypted data that can only be decrypted by us.

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To do that to create a keeper you can click on the plus sign in here or you can go on file new.

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Like I said This application allows you to manage all sorts of keys.

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What we're interested in is creating a PDP key.

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So I'm going to click on the second entry here and I'm going to click on continue.

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Now it's going to ask you for your name.

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So in my case I'm using John Wick next it's going to ask you for your email address.

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Now it is very important to understand that the people that you'll share the public key with will be

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able to see your name and your email address.

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Therefore if you want to stay anonymous and protect your privacy make sure you use the fake name that

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you created when you created your fake identity and make sure you use your private or anonymous e-mail

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in here.

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In my case S.J. and S.K. seven at a new dot in we're also going to click on the advanced options to

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select the encryption type.

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I'm going to keep this at RSA because this is a very strong encryption.

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We're going to set the key strength to the highest possible which is four thousand ninety six and you

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can also set an expiry date so that your key expires at the date that you specify in here.

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Now this would be good if you want to take your security to the next level.

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But for this course it's fine.

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I'm going to set it to never expire.

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I'll keep this ticked and I'm going to click on create to create my keeper.

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Now it's going to ask me to set a passphrase for the key.

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Make sure you set a strong and long one click.

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Okay.

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And this program is going to generate your key pair.

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And as you can see right here we have a new entry with my keeper.

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Now notice the icon here for this keeper contains two keys a silver and gold one.

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This means that this is a keeper.

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It contains a private key and a public key.

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Notice all of the other entries in here contain only one gold key which means that these entries only

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contain a public key so these can be used to encrypt data for someone else or verify the integrity of

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data.

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But there is no private key stored in here.

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Now to get more information about any of these entries you can right click and click on properties and

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in here you can see information about the owner for example the name John wake like we said it.

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The email again.

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The same email that we sent it to.

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You can see the key idea which can be used to verify the key.

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And we'll talk about that later.

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And if we go on the details you'll also see the fingerprint which can also be used to verify the key

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we actually use this when we downloaded the Tor browser.

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If you remember and as we go through this section actually you'll see how the verification steps we

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followed to verify the third browser makes sense and all of this will click with that.

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Now from here you can also export your secret key which is something that you should never do because

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like I said we should never share the secret key the secret key should always be kept privately.

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The only time that you might want to do this is if you're gonna completely wipe the system and still

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want to use the same key.

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You might want to export this.

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Store it in an encrypted USP device and then put it on your next installation.

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Other than that there is no need to export your key from here.

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From here you can also set the expiry so as as shown before we set the expiry to never.

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But if you change your mind you can click on this icon and set the key to expire at any date.

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You want and going back to the names and signatures you can see again your name and the email associated

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with this key and you can click on Add name to add more contacts to be associated with this key.

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But like I said be very careful when you're doing this because these contacts will be visible to anybody

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that can see your public key.

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And like I said in general we will be sharing our public key with a lot of people because this is the

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way this works so that they can encrypt data and send it to us.

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So now that we have the key power created in the next lecture we're going to talk about how to share

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our public key with our contacts and then we'll see how that can be used to encrypt data and verify

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integrity.