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Encrypt and sign your emails

using gpnupg public key cryptography to encrypt and sign email

The way public key cryptography works is you generate a key and upload it to a public key server. Someone wishing to send you an encrypted email or verify your email signature downloads your public key from the key server. To send someone an encrypted email, you'll need their public key.

This example uses my public key, replace with your own after generating it in step one. On Debian based systems:

Generate a gpg key:

gpg --gen-key

Enter your email address, and a password. System defaults will work for other options.

To list all keys:

gpg --list-keys

Add your key to bashrc by opening ~/.bashrc in a text editor and adding the line:

export GPGKEY=7890D0B4

Upload your public key to public keyservers:

gpg --send-keys --keyserver keyserver.ubuntu.com 7890D0B4

gpg --send-keys --keyserver wwwkeys.eu.pgp.net 7890D0B4

Another user can retrieve your key with the command:

gpg --keyserver keyserver.ubuntu.com --recv 7890D0B4

For browser webmail based encryption try the firegpg firefox extension. For Thunderbird/Iceweasel - apt-get install enigmail. A more detailed gnupg guide is here.

  1. gravatar

    # by Anonymous - June 13, 2009 at 10:50 PM

    Voltage SecureMail at http://www.voltage.com/vsn is another great email and file encryption tool. Your email address is your public key instead of a PGP key or a certificate. You can send ad-hoc email to anyone and recipients don't need any special software to read and reply securely. Encrypted mail is only stored in a sender's sent folder or a recipient's inbox.