Algorithms and OOD (CSC 207 2013F) : Handouts

Thoughts About Email and Encryption

Most of us, myself included, don't think much about email, other than that it's a convenient way to communicate. But a few recent events suggest that we should be a bit more thoughtful. Hence, I encourage you to consider using mail encryption software, particularly the GNU Privacy Guard (GPG).

Since I use GPG, I've written a really brief introduction. There are a host of more useful and more comprehensive introductions to and tutorials about GPG, so I'm not going to write much here, other than to recommend that you learn about using GPG. I will say that, depending on what email package I'm using and who I'm communicating with, encryption is either trivial (one click and one password when I'm using and sending email) or a slight pain (saving the encrypted message as a file and then running a decryption program when I'm receiving an encrypted message via Webmail).

GPG is available for all three major operating systems (and probably for others, too).

If you send me your public (or a link to your public key) and ask me to encrypt email to do you, I will do my best to remember (although I may not always succeed). You can find my public key at or at the MIT key server,

You may find it a bit strange that I'm giving you instructions for encrypting your email when I'm encouraging you to use a public IRC channel to discuss homework. But the combination is intentional. IRC channels are supposed to be public. I ask you to use an IRC channel to remind you of the benefits of working in public. In contrast, email is supposed to be private. I teach you about GPG to help you ensure that your remail remains private. You are free to judge the best balance between the two.

Copyright (c) 2013 Samuel A. Rebelsky.

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