Standards

Exchanging email is straightforward thanks to the many standards (RFCs) that have enabled its worldwide adoption. If you're looking for independence, tech sovereignty, or to be able to tweak something to make your life easier, then configuring and managing your own mail server could be just what you need.

Tech sovereignty

When you manage your own infrastructure you have sovereignty over your email for your domains, you can be confident that you're in control of receiving, managing and sending your emails. Open source means you have access to the source code, you can see how it works and modify or update it if necessary.

There is ample help, both paid and free, for when you're looking for feedback, get stuck, unsure how to implement a feature, or just want the confidence to know your email is under your control.

The history of email

An email message is often cited as RFC 822, created in 1982. The concept of sharing messages can be easily traced back to 1973 with RFC 524 in "A Proposed Mail Protocol". It has since been superseded by a number of standards that define in much more detail how a message is sent between servers and how an email is constructed.

As much as an organisation might prefer a monopoly with hidden techniques, public standards enables everyone to share the benefits creating a much larger ecosystem, email is one of those global standards. Looking at that original RFC and following the links in "Document type" and you quickly realise there are many related standards, by way of example the 822 Document type is:

Document type
RFC - Internet Standard
August 1982
Obsoleted by RFC 2822
Updated by RFC 1123, RFC 1138, RFC 1148, RFC 2156, RFC 1327
Obsoletes RFC 733

There are standards for authenticating an email RFC 6376 (DKIM), authenticating a sender RFC 7208 (SPF), and in RFC 7489 combining them enabling more comprehensive Domain-based Message Authentication, Reporting, and Conformance (DMARC).

Standards

It's these agreed upon standards that enables the largest providers and the smallest independents to work together exchanging email across countries, languages and time zones.

The following is an incomplete list of standards (RFCs) that impact DBMail.

RFC 822

Obsoleted by RFC 2822.

Standard for the format of ARPA internet text messages https://datatracker.ietf.org/doc/html/rfc822

RFC 1939

Post Office Protocol - Version 3 https://datatracker.ietf.org/doc/html/rfc1939/

RFC 2033

Local Mail Transfer Protocol https://datatracker.ietf.org/doc/html/rfc2033

RFC 2045

Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies https://datatracker.ietf.org/doc/html/rfc2045

RFC 2046

Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types https://datatracker.ietf.org/doc/html/rfc2046

RFC 2047

MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text https://datatracker.ietf.org/doc/html/rfc2047

RFC 2048

Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures https://datatracker.ietf.org/doc/html/rfc2048

RFC 2049

Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and Examples https://datatracker.ietf.org/doc/html/rfc2049

RFC 2060

The Internet Message Access Protocol, Version 4rev1 (IMAP4rev1) allows a client to access and manipulate electronic mail messages on a server.  IMAP4rev1 permits manipulation of remote message folders,
called "mailboxes", in a way that is functionally equivalent to local mailboxes.  IMAP4rev1 also provides the capability for an offline client to resynchronize with the server.

IMAP4rev1 includes operations for creating, deleting, and renaming mailboxes; checking for new messages; permanently removing messages; setting and clearing flags; [RFC-822] and [MIME-IMB] parsing; searching; and selective fetching of message attributes, texts, and portions thereof.  Messages in IMAP4rev1 are accessed by the use of numbers.  These numbers are either message sequence numbers or unique identifiers.

https://datatracker.ietf.org/doc/html/rfc2060

RFC 2086

IMAP4 Access Control List (ACL) Extension - See RFC 4314 below.

RFC 2184

MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations https://datatracker.ietf.org/doc/html/rfc2184

RFC 2231

MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations https://datatracker.ietf.org/doc/html/rfc2231

RFC 2798

Definition of the inetOrgPerson LDAP Object Class https://datatracker.ietf.org/doc/html/rfc2798

RFC 2822

Internet Message Format https://datatracker.ietf.org/doc/html/rfc2822

RFC 3463

Enhanced Mail System Status Codes https://datatracker.ietf.org/doc/html/rfc3463

RFC 3503

Message Disposition Notification (MDN) profile for Internet Message Access Protocol (IMAP) https://datatracker.ietf.org/doc/html/rfc3503

RFC 4314

IMAP4 Access Control List (ACL) Extension

The Access Control List (ACL) extension (RFC 2086) of the Internet Message Access Protocol (IMAP) permits mailbox access control lists to be retrieved and manipulated through the IMAP protocol.

This document is a revision of RFC 2086.  It defines several new access control rights and clarifies which rights are required for different IMAP commands.

https://datatracker.ietf.org/doc/html/rfc4314

RFC 4871

DomainKeys Identified Mail (DKIM) Signatures https://datatracker.ietf.org/doc/html/rfc4871

RFC 5228

Sieve: An Email Filtering Language https://datatracker.ietf.org/doc/html/rfc5228

RFC 5321

Simple Mail Transfer Protocol https://datatracker.ietf.org/doc/html/rfc5321

RFC 5322

Internet Message Format https://datatracker.ietf.org/doc/html/rfc5322

RFC 5424

The Syslog Protocol. Used to convey event notification messages. https://datatracker.ietf.org/doc/html/rfc5424

RFC 5788

IMAP4 Keyword Registry https://datatracker.ietf.org/doc/html/rfc5788

RFC 5804

A Protocol for Remotely Managing Sieve Scripts https://datatracker.ietf.org/doc/html/rfc5804

RFC 7162

IMAP Extensions: Quick Flag Changes Resynchronization (CONDSTORE) and Quick Mailbox Resynchronization (QRESYNC) https://datatracker.ietf.org/doc/html/rfc7162

RFC9051

Internet Message Access Protocol (IMAP) - Version 4rev2 https://datatracker.ietf.org/doc/html/rfc9051