Question

When was the first SMTP email sent?
What is the history of SMTP emails?

Summary

In this article we look at the history of emails and the protocol SMTP.

1970s

Electronic Mail has existed since the 1960s, but in 1971 the first email to use an ‘@’ symbol was sent over a computer network. That email was sent by Ray Tomlinson at the time he worked for BBN Technologies (Bolt, Beranek and Newman). Ray worked on various projects at BBN including the ARPANET Network Control Program.

The first email was sent on a program called SNDMSG where Ray had modified the software from just sending messages on a TENEX system to being able to send messages over a network. Originally SNDMSG allowed users of a time-share computer to send messages to one another, but it was a closed system and limited to users of a single computer.

Using some code Ray had written in another program called CPYNET (a program used for file transfers) he modified SNDMSG to be able to send messages over the ARPANET system. This was a result of personal interest of Ray’s and not something BBN had commissioned as a project.

Of course, to send messages over the network Ray needed a way to determine the user from the destination, so the @ symbol was used as a separator, and is still used in email addresses today.

During the 1970s the mechanism of sending messages over the network was in full development. There were many US universities all with their own ARPANETs and looking for a common method of communicating between the different systems.

1980s

Just like the battle between VHS and Betamax there were two rising methods for communications across networks. That being X.400 and SMTP.

In 1982 the first RFC for SMTP (Simple Mail Transfer Protocol) was published and SMTP became the clear winner of protocols for transferring messages from different systems over local networks and wide networks (like the Internet).

Jonathan Postel published the RFC821 in early August 1982 detailing the SMTP protocol. Later in the same month David Crocker published the RFC822 which detail the way message (like SMTP) could be transmitted over Internet capable networks.

Together these RFCs formed the basis of emailing today. The SMTP protocol has since been updated overs the years, namely RFC5321 in 2008 turning SMTP into Extended SMTP. There are many other protocols and RFCs that combine together to make an email system.

SMTP deals with the way emails are sent from server to server, i.e from sender to recipient’s mail server. How the recipient collects that email is governed by a serious of other protocols like POP3 (RFC1081), IMAP (RFC1730), and later years to come; MAPI, Exchange ActiveSync and various Web methods.

1990s

In 1991 a British scientist called Tim Berners-Lee invented the World Wide Web where communications between a client and server on the Internet was made possible using another protocol HTTP (HyperText Transfer Protocol), later to be published as RFC1945.

The mid 90s the Internet became more available to the ordinary people and Internet access by dial up modems was about to take off. This meant emailing was more available and a real competition to the traditional postal office (nick named snail mail).

By 1998 the best dial up speeds to the Internet were 56Kbps and a serial modem would cost up to £399. So, for the masses we’d stick to 28.8Kbps and the more affordable modems, with manufacturers like USRobitics.

2000s

In the 90s we saw the birth of the mobile (cellular) phone but it wasn't till the 00s (aka Noughties) did fast Internet access come to the portable devices. Known as 3G and 4G with speeds faster than modems and catching up ADSL broadband speeds, meant you could communicate with anyone on the move. This was great news for SMTP a protocol that was invented in the 80s but having a rebirth to cater for more and more devices and people communicating by email.

Of course, the down side to more people communicating by email meant there was also an increase in junk emails, unsolicited emails and malicious attacks by email. We now needed anti-virus software to protect us from email-borne threats as well.

Along with anti-virus protection users of email also needed to incorporate the use of spam-filtering applications or services. Services like profilter which offer a hosted protection against spam. They work kinda like a washing machine. You put all the emails in the washing machine and only the good emails (aka ham, i.e. not spam) get delivered to the recipient’s server and the bad emails (aka spam) get kept in the washing machines quarantine area.

The future

Email has seen its fair share of competition of the times. From Text Messaging (SMS) to more popular instant messaging services like Facebook Messenger, Instagram, WhatsApp, etc… And of course, video platforms like Skype, Zoom and MS Teams.

The future for emailing is still looking good, with tighter integration with groupware application and seeing the competition mentioned above not be competition anymore but working together as integrated services.
Applications like CRMs, Accounting software, eCommerce solutions all working seamlessly with emailing over SMTP and API Gateways. Integrating with services like outMail an outgoing SMTP (and API) email relay service.

Security of emailing

Remember sending emails using SMTP, a protocol from the 80s means technology has progressed and so have the scammers. There needs to be a way of protecting emails from being spoofed, for the recipients to know with confidence that the email arrived has come from the true sender, and for emails to be digitally signed and encrypted.

To support these requirements, we have seen the addition of SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail) and DMARC (Domain-based Message Authentication, Reporting & Conformance)