Yet how do emails actually find their way to their recipients? What at first seems simple (sending a message from point A to B) is actually a bit more complicated when you look behind the scenes. But people don’t normally catch wind of any of this.
The long journey through the internet
The process for sending your email starts in your email software or webmail platform. Once you’ve clicked the Send button, the message is first split into two parts. The “header” contains information about the sender and recipient as well as the subject line and date, while the actual content is found in the “body”, which contains the text and any images or attachments.
Then your email embarks on its long journey. The email client contacts our mail server and first transfers the header and then the body. The first thing our mail server then does is to scan the message with which it has just been entrusted. Does it contain any viruses or malicious content? How big is the message, and is the recipient’s inbox big enough to receive it? Once these items have been resolved, the email can then be sent to the next mail server based on the recipient’s address.
Encryption whenever possible
Upon initial contact, our mail servers immediately query whether the recipient’s mail server also supports encryption. If so, we establish an encrypted connection with the recipient sever and send the entire email in encrypted form in order to protect against snoopers hanging about on the transatlantic cable or who might easily eavesdrop on an internet node. This is important, because without encryption the content of an email is sent over the internet in plain text – much like a postcard. Even in the year 2016 there are still providers who do not yet support encryption between mail servers!
You’ve got mail!
Not so fast! The email isn’t in the recipient’s inbox yet because the mail server first has to check whether the recipient’s email address actually exists on the other end. And the next step is to check whether the message is too big. Each provider has the freedom to set its own individual email size limit. The email is also scanned for things like spam and viruses. Only then is the email finally delivered to its destination in the recipient’s inbox.
So whenever you simply click the Send button, remember that behind the scenes you’re actually setting a complex system of machinery in motion.