Encryption in emails: How does email work?
Updated: Jun 28, 2022
If you're like me, you first heard about encryption while watching The Da Vinci Code. And then ignored it for years, till you found that encryption makes the modern world go round - featuring in emails, cash withdrawals and online transactions.
The idea of encryption is simple - a message can be converted into a secret code no one can read, unless they know how to decode it (like Robert Langdon). Thanks to technology, cracking most modern day encryption is almost impossible.
So how did I get interested in encryption? Well I was trying to find out about Verifiable Credentials (VCs) and found that VC encryption is quite similar to Email encryption. Which's great, except I knew nothing about Email encryption.
I did eventually find out a few things, most notably that it's a rabbit hole. So it's only fair that I share my notes around encryption here and shorten the introduction for a few other non-techies. Here're the parts we're gonna talk about:
Let's start with...
What's new with Email?
Not much really, they've been around for a while. The point of this article is to talk about encryption, so I'm going to skip the history lesson. Tl;dr being they ruled the world before their cooler instant messaging cousins came along. But not everyone's moved to Slack and / or Telegram - I still use Email and I bet a lot of other people do.
Feel free to imagine three paragraphs here about how useful Email is, how it has changed our lives, made us better people, blah blah. Meanwhile, I'll move on and talk about...
How do emails work?
For most of us, sending an Email seems like a simple two step process:
Reality, however, is a tad different:
In reality, sending your message off into the network cloud is a bit like sending Little Red Riding Hood into the deep dark woods. You never know what might happen.
I'm not going to talk more about how the workings of email here, largely because it'll look like a copied assignment from here and here.
But now that you know your email bounces around before reaching it's destination, the answer to...
Why encrypt Emails?
...should be obvious. More on that in the next part.