Exercise 8: Securing Email Pretty Good Privacy Introduction to Cryptography NOTE: To change the image on this slide, select the picture and delete it. Then click the Pictures icon in the placeholder to insert your own image.

Background Tools: Pretty Good Privacy (PGP) - OpenPGP Mozilla Thunderbird OpenPGP is a email encryption standard. PGPTool is an application that is used to create OpenPGP keypairs and encrypt/decrypt OpenPGP messages. Mozilla Thunderbird is an email client where Enigmail, an OpenPGP add-on, is used to encrypt, digitally sign, and verify email messages. Installation: (Both tools are compatible with Windows, Linux and Mac Operating Systems) Go to the website for both tools. Install and download PGP Tools - https://pgptool.github.io/ Mozilla Thunderbird - https://www.thunderbird.net/en-US/

Background OpenPGP, or Pretty Good Privacy, using public key encryption to encrypt/decrypt messages. The receiver’s public key is used to encrypt the message. The receiver’s private key is used to decrypt a message. Communicating parties exchange public keys with each other creating a “web a trust.” Example: Sasha and Kareem want to securely communicate using OpenPGP. They 1. Create OpenPGP public/private keypairs 2. They exchange public keys 3. When Sasha sends Kareem a message, Sasha uses Kareem’s public key to encrypt the message. Kareem uses his private key to decrypt to message 4. When Kareem sends Sasha a message, Kareem encrypts the message with Sasha’s public key. Sasha uses her private key to decrypt the message.

Scenario Sasha and Kareem want to communicate securely using Pretty Good Privacy or OpenPGP. Sasha and Kareem create OpenPGP keypairs and exchange public keys. To simulate two people communicating using OpenPGP, we will use two different OpenPGP tools. Tasha is using PGPTool for OpenPGP communications, and Keith is using Mozilla Thunderbird mail client for Open PGP Communications.

Setting Up Email Addresses To simulate communication between two people using OpenPGP, you need two email addresses to complete this exercise. Most of us have one email address from Gmail, Hotmail, Yahoo etc. However, most of use do not have two email addresses. If you already two personal email addresses, you are good to go. If you do not have two email addresses, or only have one email addresses, you need to create them. You can use whatever email client you want to create the email addresses. You can use Gmail, Hotmail or Yahoo, or another email client of your choice, to create two separate email accounts, if you don’t have an email address(es) at all. Create an additional email address in your existing email client if you already have one email address. Here are links to Gmail, Hotmail, and Yahoo email setup sites if you want to use them to create the two email addresses. Write down your two email 1st Email: _____________ 2nd Email: _____________

Creating OpenPGP Public/Private KeyPairs in PGP Tools You should have installed and downloaded PGPTool. Open it to its homepage.

Creating OpenPGP Public/Private KeyPairs in PGP Tools You first have to create public/private keypairs for Sasha. Click on “Key ring” (in the upper left corner) “Create PGP key” In “Full name” type “Sasha”. You are going to associate Sasha with your first email address that you wrote down. Type that email in “Email.” Create a strong paraphrase and click “Create.”

Creating OpenPGP Public/Private KeyPairs in PGP Tools On the PGP Tool homepage, click The keypair you create for “Sasha” is now placed in the key ring.

Title and Content Layout with Chart

Two Content Layout with Table First bullet point here Second bullet point here Third bullet point here Class Group 1 Group 2 Class 1 82 95 Class 2 76 88 Class 3 84 90

Title and Content Layout with SmartArt Task description Step 1 Title Step 2 Title Step 3 Title Step 4 Title

Picture with Caption Layout

Add a Slide Title - 1

Add a Slide Title - 2

Add a Slide Title - 3

Add a Slide Title - 4

Add a Slide Title - 5