Bài Thực Hành Số 5 E-mail Encryption Using Gmail, Firefox & GNUPG (FirePGP)

Step 1: The Programs Needed

This is the simplest combination of programs for encryption.

You will need windows, a Firefox browser and a Gmail account as well as GPG4Win and FireGPG.

GPG4Win does the encryption on a windows machine.
FireGPG adds encryption functionality in Gmail.

Step 2: How Encryption Works

Encryption is really very simple, but many people try to make it sound complicated.

• Every person have a pair of keys. 
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• Each key is a number that fits in an equation.
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• One key is shared with everyone, and is called the "public key".
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• One key is private and you hide it on your computer or on you flash disk and this is called a "private key".

The e-mail cannot be opened without using both keys.

The person sending you an encrypt e-mail must know your public key in order to encrypt it. The e-mail cannot be opened except with your private key which you only have.

 

Step 3: Sending Encrypted e-mail

If Bond wants to send Q an encrypted message he needs Q's public key.

There are three ways for Bond o get Q's public key:

1. Q can give his public key to Bond physically, like, say, on a flash disk or some other physical media. This the safest most secure method of communication. Because anybody that tries to decrypt need to know the two keys.

2. Q can e-mail his public key to bond. This is slightly less secure.

3.Q can post his public key on a server, like a keyserver or his website or even Instructables. Now one key is known to the public but the other key is unkown. This exactly half as secure as method 1.

I will post Q's public key here. It also available on the keyserver http://subkeys.pgp.net.

Q's e-mail is quartermaster007@gmail.com.

You can send to antoanthongtin.edu.vn@gmail.com encrypted messages as practice.