Electronic Mail / Internet Fax

Cyrus IMAP / SASL

Cyrus IMAP Server Project - Carnegie Mellon University
Cyrus IMAP Server Documentation - Carnegie Mellon University
Paranoid Penguin: Secure Mail with LDAP and IMAP, Part 1 - LinuxJournal.com - Part 2 covers Cyrus IMAP and Postfix
Cyrus IMAP Mailbox Recovery - AFP548.com
Re: LMTP question - Article on LMTP Authentication appearing on one of the Cyrus lists
Re: cannot connect to saslauthd server: No such file or directory [solved] - List message re: saslauthd problem resolution (one of many with saslauthd) - irbs.net
fatal: no SASL authentication mechanisms - List message re: getting saslauthd working with postfix and Cyrus IMAPD. Good followup to this original post can be found at here - neohapsis.com
Cyrus IMAPd RPM Packages - invoca.ch
Autocreate INBOX patch for Cyrus - This was a very useful patch but no longer maintained and not applicable to current Cyrus IMAP releases - uoa.gr

Postfix

Postfix Documentation - postfix.org
Postfix Howtos and FAQs - postfix.org
Large-Scale Mail with Postfix, OpenLDAP and Courier - David Dribin and Keith Garner, LinuxJournal, February 2003
Postfix-Cyrus-Web-cyradm-HOWTO - Luc de Louw
Postfix and alternative, non-IP based relay concepts - SMTP Authentication and Certificate Based Relaying with Postfix
Postfix SMTP AUTH (and TLS) HOWTO - postfix.state-of-mind.de
saslfinger - Bash utility that seeks to help with debugging SMTP AUTH setups - Patrick Koetter - postfix.state-of-mind.de

Distribution (Mailing) List Management

Mailman - GNU Mailing List Manager - python based - list.org Documentation: List Member Manual, List Management Guide, User Guide for List Subscribers, Installation Manual, List Administration Manual

Web Mail

Horde Framework / Web Mail Client - horde.org
Roundcube Webmail - roundcube.net
SquirrelMail - Webmail For Nuts - squirrelmail.org
IMAP Proxy - Almost mandatory performance enhancement for web mail clients - imapproxy.org

Standards / Recommendations

This section was last updated August, 2015

Simple Mail Transfer Protocol (SMTP) and Other Transport Protocols

RFC 788 - Simple Mail Transfer Protocol (Obsoletes RFC 780) (Obsoleted by RFC 821) (Status: UNKNOWN)
RFC 821 - Simple Mail Transfer Protocol (Obsoletes RFC 788) (Obsoleted by RFC 2821) (Also STD0010) (Status: INTERNET STANDARD)
RFC 1047 - Duplicate messages and SMTP (Status: UNKNOWN)
RFC 1090 - SMTP on X.25 (Status: UNKNOWN)
RFC 1159 - Message Send Protocol (Obsoleted by RFC 1312) (Status: EXPERIMENTAL)
RFC 1204 - Message Posting Protocol (Status: EXPERIMENTAL)
RFC 1312 - Message Send Protocol 2 (Obsoletes RFC 1159) (Status: EXPERIMENTAL)
RFC 1425 - SMTP Service Extensions (Obsoleted by RFC 1651) (Status: PROPOSED STANDARD)
RFC 1426 - SMTP Service Extension for 8bit-MIMEtransport (Obsoleted by RFC 1652) (Status: PROPOSED STANDARD)
RFC 1427 - SMTP Service Extension for Message Size Declaration (Obsoleted by RFC 1653) (Status: PROPOSED STANDARD)
RFC 1428 - Transition of Internet Mail from Just-Send-8 to 8bit-SMTP/MIME (Status: INFORMATIONAL)
RFC 1651 - SMTP Service Extensions (Obsoletes RFC 1425) (Obsoleted by RFC 1869) (Status: DRAFT STANDARD)
RFC 1652 - SMTP Service Extension for 8bit-MIMEtransport (Obsoletes RFC 1426) (Obsoleted by RFC 6152) (Status: DRAFT STANDARD)
RFC 1653 - SMTP Service Extension for Message Size Declaration (Obsoletes RFC 1427) (Obsoleted by RFC 1870) (Status: DRAFT STANDARD)
RFC 1830 - SMTP Service Extensions for Transmission of Large and Binary MIME Messages (Obsoleted by RFC 3030) (Status: EXPERIMENTAL)
RFC 1845 - SMTP Service Extension for Checkpoint/Restart (Status: EXPERIMENTAL)
RFC 1846 - SMTP 521 Reply Code (Status: EXPERIMENTAL)
RFC 1854 - SMTP Service Extension for Command Pipelining (Obsoleted by RFC 2197) (Status: PROPOSED STANDARD)
RFC 1869 - SMTP Service Extensions (Obsoletes RFC 1651) (Obsoleted by RFC 2821) (Also STD0010) (Status: INTERNET STANDARD)
RFC 1870 - SMTP Service Extension for Message Size Declaration (Obsoletes RFC 1653) (Also STD0010) (Status: INTERNET STANDARD)
RFC 1891 - SMTP Service Extension for Delivery Status Notifications (Obsoleted by RFC 3461) (Status: PROPOSED STANDARD)
RFC 1893 - Enhanced Mail System Status Codes (Obsoleted by RFC 3463) (Status: PROPOSED STANDARD)
RFC 1894 - An Extensible Message Format for Delivery Status Notifications (Obsoleted by RFC 3464) (Updated by RFC 2852) (Status: PROPOSED STANDARD)
RFC 1985 - SMTP Service Extension for Remote Message Queue Starting (Status: PROPOSED STANDARD)
RFC 2033 - Local Mail Transfer Protocol (Status: INFORMATIONAL)
RFC 2034 - SMTP Service Extension for Returning Enhanced Error Codes (Status: PROPOSED STANDARD)
RFC 2197 - SMTP Service Extension for Command Pipelining (Obsoletes RFC 1854) (Obsoleted by RFC 2920) (Status: PROPOSED STANDARD)
RFC 2442 - The Batch SMTP Media Type (Status: INFORMATIONAL)
RFC 2476 - Message Submission (Obsoleted by RFC 4409) (Status: PROPOSED STANDARD)
RFC 2487 - SMTP Service Extension for Secure SMTP over TLS (Obsoleted by RFC 3207) (Status: PROPOSED STANDARD)
RFC 2524 - Neda's Efficient Mail Submission and Delivery (EMSD) Protocol Specification Version 1.3 (Status: INFORMATIONAL)
RFC 2554 - SMTP Service Extension for Authentication (Obsoleted by RFC 4954) (Status: PROPOSED STANDARD)
RFC 2645 - ON-DEMAND MAIL RELAY (ODMR) SMTP with Dynamic IP Addresses (Status: PROPOSED STANDARD)
RFC 2821 - Simple Mail Transfer Protocol (Obsoletes RFC 821, RFC 974, RFC 1869) (Obsoleted by RFC 5321) (Updated by RFC 5336) (Status: PROPOSED STANDARD)
RFC 2852 - Deliver By SMTP Service Extension (Updates RFC 1894) (Status: PROPOSED STANDARD)
RFC 2920 - SMTP Service Extension for Command Pipelining (Obsoletes RFC 2197) (Also STD0060) (Status: STANDARD)
RFC 3030 - SMTP Service Extensions for Transmission of Large and Binary MIME Messages (Obsoletes RFC 1830) (Status: PROPOSED STANDARD)
RFC 3207 - SMTP Service Extension for Secure SMTP over Transport Layer Security (Obsoletes RFC 2487) (Status: PROPOSED STANDARD)
RFC 3461 - Simple Mail Transfer Protocol (SMTP) Service Extension for Delivery Status Notifications (DSNs) (Obsoletes RFC 1891) (Updated by RFC 3798, RFC 3885, RFC 5337, RFC 6533) (Status: DRAFT STANDARD)
RFC 3463 - Enhanced Mail System Status Codes (Obsoletes RFC 1893) (Updated by RFC 3886, RFC 4468, RFC 4865, RFC 4954, RFC 5248) (Status: DRAFT STANDARD)
RFC 3848 - ESMTP and LMTP Transmission Types Registration (Status: DRAFT STANDARD)
RFC 3865 - A No Soliciting Simple Mail Transfer Protocol (SMTP) Service Extension (Status: PROPOSED STANDARD)
RFC 3885 - SMTP Service Extension for Message Tracking (Updates RFC 3461) (Status: PROPOSED STANDARD)
RFC 3974 - SMTP Operational Experience in Mixed IPv4/v6 Environments (Status: INFORMATIONAL)
RFC 4405 - SMTP Service Extension for Indicating the Responsible Submitter of an E-Mail Message (Status: EXPERIMENTAL)
RFC 4409 - Message Submission for Mail (Obsoletes RFC 2476) (Obsoleted by RFC 6409) (Status: DRAFT STANDARD)
RFC 4468 - Message Submission BURL Extension (Updates RFC 3463) (Updated by RFC 5248) (Status: PROPOSED STANDARD)
RFC 4865 - SMTP Submission Service Extension for Future Message Release (Updates RFC 3463, RFC 3464) (Status: PROPOSED STANDARD)
RFC 4954 - SMTP Service Extension for Authentication (Obsoletes RFC 2554) (Updates RFC 3463) (Updated by RFC 5248) (Status: PROPOSED STANDARD)
RFC 5068 - Email Submission Operations: Access and Accountability Requirements (Also BCP0134) (Status: BEST CURRENT PRACTICE)
RFC 5248< - A Registry for SMTP Enhanced Mail System Status Codes (Updates RFC 3463, RFC 4468, RFC 4954) (Also BCP0138) (Status: BEST CURRENT PRACTICE)
RFC 5321 - Simple Mail Transfer Protocol (Obsoletes RFC 2821) (Updates RFC 1123) (Updated by RFC 7504) (Status: DRAFT STANDARD)
RFC 5336 - SMTP Extension for Internationalized Email Addresses (Obsoleted by RFC 6531) (Updates RFC 2821, RFC 2822, RFC 4952) (Status: EXPERIMENTAL)
RFC 5337 - Internationalized Delivery Status and Disposition Notifications (Obsoleted by RFC 6533) (Updates RFC 3461, RFC 3462, RFC 3464, RFC 3798) (Status: EXPERIMENTAL)
RFC 6152 - SMTP Service Extension for 8-bit MIME Transport (Obsoletes RFC 1652) (Also STD0071) (Status: STANDARD)
RFC 6409 - Message Submission for Mail (Obsoletes RFC 4409) (Also STD0072) (Status: STANDARD)
RFC 6531 - SMTP Extension for Internationalized Email (Obsoletes RFC 5336) (Status: PROPOSED STANDARD)
RFC 6710 - Simple Mail Transfer Protocol Extension for Message Transfer Priorities (Status: PROPOSED STANDARD)
RFC 6758 - Tunneling of SMTP Message Transfer Priorities (Status: INFORMATIONAL)
RFC 7372 - Email Authentication Status Codes (Updates RFC 7208) (Status: PROPOSED STANDARD)
RFC 7504 - SMTP 521 and 556 Reply Codes (Updates RFC 1846, RFC 5321) (Status: PROPOSED STANDARD)

RFC 733 - Standard for the format of ARPA network text messages (Obsoletes RFC 724) (Obsoleted by RFC 822) (Status: UNKNOWN)
RFC 822 - Standard For The Format Of ARPA Internet Text Messages (Obsoletes RFC 733) (Obsoleted by RFC 2822) (Updated by RFC 1123, RFC 2156, RFC 1327, RFC 1138, RFC 1148) (Also STD0011) (Status: INTERNET STANDARD)
RFC 886 - Proposed standard for message header munging (Status: UNKNOWN)
RFC 934 - Proposed standard for message encapsulation (Status: UNKNOWN)
RFC 1049 - Content-type header field for Internet messages (Status: HISTORIC)
RFC 1153 - Digest message format (Status: EXPERIMENTAL)
RFC 1154 - Encoding header field for internet messages (Obsoleted by RFC 1505) (Status: EXPERIMENTAL)
RFC 1341 - MIME (Multipurpose Internet Mail Extensions): Mechanisms for Specifying and Describing the Format of Internet Message Bodies (Obsoleted by RFC 1521) (Status: PROPOSED STANDARD)
RFC 1342 - Representation of Non-ASCII Text in Internet Message Headers (Obsoleted by RFC 1522) (Status: PROPOSED STANDARD)
RFC 1344 - Implications of MIME for Internet Mail Gateways (Status: INFORMATIONAL)
RFC 1437 - The Extension of MIME Content-Types to a New Medium (Status: INFORMATIONAL)
RFC 1505 - Encoding Header Field for Internet Messages (Obsoletes RFC 1154) (Status: EXPERIMENTAL)
RFC 1521 - MIME (Multipurpose Internet Mail Extensions) Part One: Mechanisms for Specifying and Describing the FOrmat of Internet Message Bodies (Obsoletes RFC 1341) (Obsoleted by RFC 2045, RFC 2046, RFC 2047, RFC 2048, RFC 2049) (Updated by RFC 1590) (Status: DRAFT STANDARD)
RFC 1522 - MIME (Multipurpose Internet Mail Extensions) Part Two: Message Header Extensions for Non-ASCII Text (Obsoletes RFC 1342) (Obsoleted by RFC 2045, RFC 2046, RFC 2047, RFC 2048, RFC 2049) (Status: DRAFT STANDARD)
RFC 1806 - Communicating Presentation Information in Internet Messages: The Content-Disposition Header (Obsoleted by RFC 2183) (Status: EXPERIMENTAL)
RFC 1848 - MIME Object Security Services (Status: HISTORIC)
RFC 1864 - The Content-MD5 Header Field (Obsoletes RFC 1544) (Status: DRAFT STANDARD)
RFC 2017 - Definition of the URL MIME External-Body Access-Type (Status: PROPOSED STANDARD)
RFC 2045 - Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies (Obsoletes RFC 1521, RFC 1522, RFC 1590) (Updated by RFC 2184, RFC 2231, RFC 5335, RFC 6532) (Status: DRAFT STANDARD)
RFC 2046 - Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types (Obsoletes RFC 1521, RFC 1522, RFC 1590) (Updated by RFC 2646, RFC 3798, RFC 5147, RFC 6657) (Status: DRAFT STANDARD)
RFC 2047 - MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text (Obsoletes RFC 1521, RFC 1522, RFC 1590) (Updated by RFC 2184, RFC 2231) (Status: DRAFT STANDARD)
RFC 2048 - Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures (Obsoletes RFC 1521, RFC 1522, RFC 1590) (Obsoleted by RFC 4288, RFC 4289) (Updated by RFC 3023) (Status: BEST CURRENT PRACTICE)
RFC 2049 - Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and Examples (Obsoletes RFC 1521, RFC 1522, RFC 1590) (Status: DRAFT STANDARD)
RFC 2076 - Common Internet Message Headers (Status: INFORMATIONAL)
RFC 2077 - The Model Primary Content Type for Multipurpose Internet Mail Extensions (Status: PROPOSED STANDARD)
RFC 2111 - Content-ID and Message-ID Uniform Resource Locators (Obsoleted by RFC 2392) (Status: PROPOSED STANDARD)
RFC 2183 - Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field (Obsoletes RFC 1806) (Updated by RFC 2184, RFC 2231) (Status: PROPOSED STANDARD)
RFC 2298 - An Extensible Message Format for Messge Disposition Notifications (Obsoleted by RFC 3798) (Status: PROPOSED STANDARD)
RFC 2310 - The Safe Response Header Field (Status: EXPERIMENTAL)
RFC 2369 - The Use of URLs as Meta-Syntax for Core Mail List Commands and their Transport through Message Header Fields (Status: PROPOSED STANDARD)
RFC 2425 - A MIME Content-Type for Directory Information (Obsoleted by RFC 6350) (Status: PROPOSED STANDARD)
RFC 2426 - vCard MIME Directory Profile (Obsoleted by RFC 6350) (Status: PROPOSED STANDARD)
RFC 2822 - Internet Message Format (Obsoletes RFC 822) (Obsoleted by RFC 5322) (Updated by RFC 5335, RFC 5336) (Status: PROPOSED STANDARD)
RFC 2919 - List-Id: A structured Field and Namespace for the Identification of Mailing Lists (Status: PROPOSED STANDARD)
RFC 2927 - MIME Directory Profile for LDAP Schema (Status: INFORMATIONAL)
RFC 2938 - Identifying Composite Media Features (Updates RFC 2533) (Status: PROPOSED STANDARD)
RFC 3459 - Critical Content Multi-purpose Internet Mail Extensions (MIME) Parameter (Updates RFC 3204) (Updated by RFC 5621) (Status: PROPOSED STANDARD)
RFC 3464 - An Extensible Message Format for Delivery Status Notifications (Obsoletes RFC 1894) (Updated by RFC 4865, RFC 5337, < a href="/rfc/rfc6533.txt" target="_blank">RFC 6533) (Status: DRAFT STANDARD)
RFC 3798 - Message Disposition Notification (Obsoletes RFC 2298) (Updates RFC 3461, RFC 2046) (Updated by RFC 5337, RFC 6533) (Status: DRAFT STANDARD)
RFC 3864 - Registration Procedures for Message Header Fields (Also BCP0090) (Status: BEST CURRENT PRACTICE)
RFC 3886 - An Extensible Message Format for Message Tracking Responses (Updates RFC 3463) (Status: PROPOSED STANDARD)
RFC 3887 - Message Tracking Query Protocol (Status: PROPOSED STANDARD)
RFC 3888 - Message Tracking Model and Requirements (Status: INFORMATIONAL)
RFC 4021 - Registration of Mail and MIME Header Fields (Updated by RFC 5322) (Status: PROPOSED STANDARD)
RFC 4141 - SMTP and MIME Extensions for Content Conversion (Status: PROPOSED STANDARD)
RFC 4249 - Implementer-Friendly Specification of Message and MIME-Part Header Fields and Field Components (Status: INFORMATIONAL)
RFC 4289 - Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures (Obsoletes RFC 2048) (Also BCP0013) (Status: BEST CURRENT PRACTICE)
RFC 5064 - The Archived-At Message Header Field (Status: PROPOSED STANDARD)
RFC 5322 - Internet Message Format (Obsoletes RFC 2822) (Updates RFC 4021) (Updated by RFC 6854) (Status: DRAFT STANDARD)
RFC 5335 - Internationalized Email Headers (Obsoleted by RFC 6532) (Updates RFC 2045, RFC 2822) (Status: EXPERIMENTAL)
RFC 5451 - Message Header Field for Indicating Message Authentication Status (Obsoleted by RFC 7001) (Updated by RFC 6577) (Status: PROPOSED STANDARD)
RFC 6532 - Internationalized Email Headers (Obsoletes RFC 5335) (Updates RFC 2045) (Status: PROPOSED STANDARD)
RFC 6533 - Internationalized Delivery Status and Disposition Notifications (Obsoletes RFC 5337) (Updates RFC 3461, RFC 3464, RFC 3798, RFC 6522) (Status: PROPOSED STANDARD)
RFC 6729 - Indicating Email Handling States in Trace Fields (Status: PROPOSED STANDARD)
RFC 6854 - Update to Internet Message Format to Allow Group Syntax in the "From:" and "Sender:" Header Fields (Updates RFC 5322) (Status: PROPOSED STANDARD)
RFC 7001 - Message Header Field for Indicating Message Authentication Status (Obsoletes RFC 5451, RFC 6577) (Updated by RFC 7410) (Status: PROPOSED STANDARD)

MIME Media and Content Types

RFC 1523 - The text/enriched MIME Content-type (Obsoleted by RFC 1563, RFC 1896) (Status: INFORMATIONAL)
RFC 1563 - The text/enriched MIME Content-type (Obsoletes RFC 1523) (Obsoleted by RFC 1896) (Status: INFORMATIONAL)
RFC 1740 - MIME Encapsulation of Macintosh Files - MacMIME (Status: PROPOSED STANDARD)
RFC 1741 - MIME Content Type for BinHex Encoded Files (Status: INFORMATIONAL)
RFC 1767 - MIME Encapsulation of EDI Objects (Status: PROPOSED STANDARD)
RFC 1872 - The MIME Multipart/Related Content-type (Obsoleted by RFC 2112) (Status: EXPERIMENTAL)
RFC 1873 - Message/External-Body Content-ID Access Type (Status: EXPERIMENTAL)
RFC 1895 - The Application/CALS-1840 Content-type (Status: INFORMATIONAL)
RFC 1896 - The text/enriched MIME Content-type (Obsoletes RFC 1523, RFC 1563) (Status: INFORMATIONAL)
RFC 1927 - Suggested Additional MIME Types for Associating Documents (Status: INFORMATIONAL)
RFC 2110 - MIME E-mail Encapsulation of Aggregate Documents, such as HTML (MHTML) (Obsoleted by RFC 2557) (Status: PROPOSED STANDARD)
RFC 2112 - The MIME Multipart/Related Content-type (Obsoletes RFC 1872) (Obsoleted by RFC 2387) (Status: PROPOSED STANDARD)
RFC 2161 - A MIME Body Part for ODA (Status: EXPERIMENTAL)
RFC 2220 - The Application/MARC Content-type (Status: INFORMATIONAL)
RFC 2318 - The text/css Media Type (Status: INFORMATIONAL)
RFC 2387 - The MIME Multipart/Related Content-type (Obsoletes RFC 2112) (Status: PROPOSED STANDARD)
RFC 2503 - MIME Types for Use with the ISO ILL Protocol (Status: INFORMATIONAL)
RFC 2506 - Media Feature Tag Registration Procedure (Status: BEST CURRENT PRACTICE)
RFC 2530 - Indicating Supported Media Features Using Extensions to DSN and MDM (Status: PROPOSED STANDARD)
RFC 2533 - A Syntax for Describing Media Feature Sets (Updated by RFC 2738, RFC 2938) (Status: PROPOSED STANDARD)
RFC 2557 - MIME Encapsulation of Aggregae Documents, such as HTML (MHTML) (Obsoletes RFC 2110) (Status: PROPOSED STANDARD)
RFC 2586 - The Audio/L16 MIME content type (Status: INFORMATIONAL)
RFC 2646 - The Text/Plain Format Parameter (Obsoleted by RFC 3676) (Updates RFC 2046) (Status: PROPOSED STANDARD)
RFC 2652 - MIME Object Definitions for the Common Indexing Protocol (CIP) (Status: PROPOSED STANDARD)
RFC 2586 - The Audio/L16 MIME content type (Status: INFORMATIONAL)
RFC 2854 - The 'text/html' Media Type (Obsoletes RFC 2070, RFC 1980, RFC 1942, RFC 1867, RFC 1866) (Status: INFORMATIONAL)
RFC 2856 - Textual Conventions for Additional High Capacity Data Types (Status: PROPOSED STANDARD)
RFC 2912 - Indicating Media Features for MIME Content (Status: PROPOSED STANDARD)
RFC 2913 - MIME Content Types in Media Feature Expressions (Status: PROPOSED STANDARD)
RFC 2957 - The application/whoispp-query Content-Type (Status: INFORMATIONAL)
RFC 2958 - The application/whoispp-response Content-type (Status: INFORMATIONAL)
RFC 3003 - The audio/mpeg Media Type (Status: PROPOSED STANDARD)
RFC 3009 - Registration of parityfec MIME types (Obsoleted by RFC 5109) (Status: PROPOSED STANDARD)
RFC 3204 - MIME media types for ISUP and QSIG Objects (Updated by RFC 3459, RFC 5621) (Status: PROPOSED STANDARD)
RFC 3240 - Digital Imaging and Communications in Medicine (DICOM) - Application/dicom MIME Sub-type Registration (Status: PROPOSED STANDARD)
RFC 3236 - The 'application/xhtml+xml' Media Type (Status: INFORMATIONAL)
RFC 3391 - The MIME Application/Vnd.pwg-multiplexed Content-Type (Status: INFORMATIONAL)
RFC 3420 - Internet Media Type message/sipfrag (Status: PROPOSED STANDARD)
RFC 3534 - The application/ogg Media Type (Obsoleted by RFC 5334) (Status: PROPOSED STANDARD)
RFC 3548 - The Base16, Base32, and Base64 Data Encodings (Obsoleted by RFC 4648) (Status: INFORMATIONAL)
RFC 3676 - The Text/Plain Format and DelSp Parameters (Obsoletes RFC 2646) (Status: PROPOSED STANDARD)
RFC 3745 - MIME Type Registrations for JPEG 2000 (ISO/IEC 15444) (Status: PROPOSED STANDARD)
RFC 3778 - The application/pdf Media Type (Status: INFORMATIONAL)
RFC 3823 - MIME Media Type for the Systems Biology Markup Language (SBML) (Status: INFORMATIONAL)
RFC 3839 - MIME Type Registrations for 3rd Generation Partnership Project (3GPP) Multimedia files (Updated by RFC 6381) (Status: PROPOSED STANDARD)
RFC 3870 - application/rdf+xml Media Type Registration (Status: INFORMATIONAL)
RFC 3902 - The "application/soap+xml" media type (Status: INFORMATIONAL)
RFC 4047 - MIME Sub-type Registrations for Flexible Image Transport System (FITS) (Status: INFORMATIONAL)
RFC 4102 - Registration of the text/red MIME Sub-Type (Updated by RFC 6354) (Status: PROPOSED STANDARD)
RFC 4155 - The application/mbox Media Type (Status: INFORMATIONAL)
RFC 4180 - Common Format and MIME Type for Comma-Separated Values (CSV) Files (Updated by RFC 7111) (Status: INFORMATIONAL)
RFC 4263 - Media Subtype Registration for Media Type text/troff (Status: INFORMATIONAL)
RFC 4267 - The W3C Speech Interface Framework Media Types: application/voicexml+xml, application/ssml+xml, application/srgs, application/srgs+xml, application/ccxml+xml, and application/pls+xml (Status: INFORMATIONAL)
RFC 4288 - Media Type Specifications and Registration Procedures (Obsoletes RFC 2048) (Obsoleted by RFC 6838) (Also BCP0013) (Status: BEST CURRENT PRACTICE)
RFC 4337 - MIME Type Registration for MPEG-4 (Updated by RFC 6381) (Status: PROPOSED STANDARD)
RFC 4374 - The application/xv+xml Media Type (Status: INFORMATIONAL)
RFC 4393 - MIME Type Registrations for 3GPP2 Multimedia Files (Updated by RFC 6381) (Status: PROPOSED STANDARD)
RFC 4536 - The application/smil and application/smil+xml Media Types (Status: INFORMATIONAL)
RFC 4539 - Media Type Registration fo the Society of Motion Picture and Television Engineers (SMPTE) Material Exchange Format (MXF) (Status: INFORMATIONAL)
RFC 4573 - MIME Type Registration for RTP Payload Format for H.224 (Status: PROPOSED STANDARD)
RFC 4613 - Media Type Registrations for Downloadable Sounds for Musical Instrument Digital Interface (MIDI) (Status: INFORMATIONAL)
RFC 4627 - The application/json Media Type for JavaScript Object Notation (JSON) (Obsoleted by RFC 7159) (Status: INFORMATIONAL)
RFC 4648 - The Base16, Base32, and Base64 Data Encodings (Obsoletes RFC 3548) (Status: PROPOSED STANDARD)
RFC 4723 - Registration of Media Type audio/mobile-xmf (Status: INFORMATIONAL)
RFC 4735 - Example Media Types for Use in Documentation (Status: PROPOSED STANDARD)
RFC 4855 - Media Type Registration of RTP Payload Formats (Obsoletes RFC 3555) (Status: PROPOSED STANDARD)
RFC 4856 - Media Type Registration of Payload Formats in the RTP Profile for Audio and Video Conferences (Obsoletes RFC 3555) (Status: PROPOSED STANDARD)
RFC 5334 - Ogg Media Types (Obsoletes RFC 3534) (Status: PROPOSED STANDARD)
RFC 5877 - The application/pkix-attr-cert Media Type for Attribute Certificates (Status: INFORMATIONAL)
RFC 5955 - The application/timestamped-data Media Type (Updates RFC 5544) (Status: INFORMATIONAL)
RFC 5967 - The application/pkcs10 Media Type (Updates RFC 2986) (Status: INFORMATIONAL)
RFC 6129 - The 'application/tel+xml' Media Type (Status: INFORMATIONAL)
RFC 6207 - The Media Types application/mods+xml, application/mads+xml, application/mets+xml, application/marcxml+xml, and application/sru+xml (Status: INFORMATIONAL)
RFC 6657 - Update to MIME regarding "charset" Parameter in Textual Media Types (Updates RFC 2046) (Status: PROPOSED STANDARD)
RFC 6713 - The 'application/zlib' and 'application/gzip' Media Types (Status: INFORMATIONAL)
RFC 6838 - Media Type Specifications and Registration Procedures (Obsoletes RFC 4288) (Also BCP0013) (Status: BEST CURRENT PRACTICE)
RFC 6839 - Additional Media Type Structured Syntax Suffixes (Updates RFC 3023) (Updated by RFC 7303) (Status: INFORMATIONAL)
RFC 6922 - The application/sql Media Type (Status: INFORMATIONAL)
RFC 7303 - XML Media Types (Obsoletes RFC 3023) (Updates RFC 6839) (Status: PROPOSED STANDARD)

Languages and Character Sets

RFC 1345 - Character Mnemonics and Character Sets (Status: INFORMATIONAL)
RFC 1456 - Conventions for Encoding the Vietnamese Language VISCII: VIetnamese Standard Code for Information Interchange VIQR: VIetnamese Quoted-Readable Specification (Status: INFORMATIONAL)
RFC 1468 - Japanese Character Encoding for Internet Messages (Status: INFORMATIONAL)
RFC 1489 - Registration of a Cyrillic Character Set (Status: INFORMATIONAL)
RFC 1554 - ISO-2022-JP-2: Multilingual Extension of ISO-2022-JP (Status: INFORMATIONAL)
RFC 1555 - Hebrew Character Encoding for Internet Messages (Status: INFORMATIONAL)
RFC 1556 - Handling of Bi-directional Texts in MIME (Status: INFORMATIONAL)
RFC 1557 - Korean Character Encoding for Internet Messages (Status: INFORMATIONAL)
RFC 1641 - Using Unicode with MIME (Status: EXPERIMENTAL)
RFC 1642 - UTF-7 - A Mail-Safe Transformation Format of Unicode (Obsoleted by RFC 2152) (Status: EXPERIMENTAL)
RFC 1766 - Tags for the Identification of Languages (Obsoleted by RFC 3066, RFC 3282) (Status: PROPOSED STANDARD)
RFC 1815 - Character Sets ISO-10646 and ISO-10646-J-1 (Status: INFORMATIONAL)
RFC 1842 - ASCII Printable Characters-Based Chinese Character Encoding for Internet Messages (Status: INFORMATIONAL)
RFC 1843 - HZ - A Data Format for Exchanging Files of Arbitrarily Mixed Chinese and ASCII Characters (Status: INFORMATIONAL)
RFC 1922 - Chinese Character Encoding for Internet Messages (Status: INFORMATIONAL)
RFC 1947 - Greek Character Encoding for Electronic Mail Messages (Status: INFORMATIONAL)
RFC 2044 - UTF-8, a transformation format of Unicode and ISO 10646 (Obsoleted by RFC 2279) (Status: INFORMATIONAL)
RFC 2152 - UTF-7 A Mail-Safe Transformation Format of Unicode (Obsoletes RFC 1642) (Status: INFORMATIONAL)
RFC 2184 - MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations (Obsoleted by RFC 2231) (Updates RFC 2047, RFC 2183) (Status: PROPOSED STANDARD)
RFC 2231 - MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations (Obsoletes RFC 2184) (Updates RFC 2045, RFC 2047, RFC 2183) (Status: PROPOSED STANDARD)
RFC 2237 - Japanese Character Encoding for Internet Messages (Status: INFORMATIONAL)
RFC 2279 - UTF-8, a transformation format of ISO 10646 (Obsoletes RFC 2044) (Obsoleted by RFC 3629) (Status: PROPOSED STANDARD)
RFC 2319 - Ukranian Character Set KOI8-U (Status: INFORMATIONAL)
RFC 2482 - Language Tagging in Unicode Plain Text (Obsoleted by RFC 6082) (Status: HISTORIC)
RFC 2781 - UTF-16, and encoding of ISO 10646 (Status: INFORMATIONAL)
RFC 2987 - Registration of Charset and Languages Media Features Tags (Status: PROPOSED STANDARD)
RFC 3282 - Content Language Headers (Obsoletes RFC 1766) (Status: DRAFT STANDARD)
RFC 3454 - Preparation of Internationalized Strings ("stringprep") (Obsoleted by RFC 7564) (Status: PROPOSED STANDARD)
RFC 3629 - UTF-8, a transformation format of ISO 10646 (Obsoletes RFC 2279) (Also STD0063) (Status: STANDARD)
RFC 4042 - UTF-9 and UTF-18 Efficient Transformation Formats of Unicode (Status: INFORMATIONAL)
RFC 4645 - Initial Language Subtag Registry (Status: INFORMATIONAL)
RFC 4646 - Tags for Identifying Languages (Obsoletes RFC 3066) (Obsoleted by RFC 5646) (Status: BEST CURRENT PRACTICE)
RFC 4647 - Matching of Language Tags (Obsoletes RFC 3066) (Also BCP0047) (Status: BEST CURRENT PRACTICE)
RFC 5051 - i;unicode-casemap - Simple Unicode Collation Algorithm (Status: PROPOSED STANDARD)
RFC 5137 - ASCII Escaping of Unicode Characters (Also BCP0137) (Status: BEST CURRENT PRACTICE)
RFC 5198 - Unicode Format for Network Interchange (Obsoletes RFC 0698) (Updates RFC 0854) (Status: PROPOSED STANDARD)
RFC 5504 - Downgrading Mechanism for Email Address Internationalization (Obsoleted by RFC 6530) (Status: EXPERIMENTAL)
RFC 5645 - Update to the Language Subtag Registry (Status: INFORMATIONAL)
RFC 5646 - Tags for Identifying Languages (Obsoletes RFC 4646) (Also BCP0047) (Status: BEST CURRENT PRACTICE)
RFC 5825 - Displaying Downgraded Messages for Email Address Internationalization (Obsoleted by RFC 6530) (Status: EXPERIMENTAL)
RFC 6082 - Depreciating Unicode Language Tag Characters: RFC 2482 is Historic (Obsoletes RFC 2482) (Status: INFORMATIONAL)

Lemonade / Diverse Service Environments / Mobile

RFC 4356 - Mapping Between the Multimedia Messaging Service (MMS) and Internet Mail (Status: PROPOSED STANDARD)
RFC 4416 - Goals for Internet Messaging to Support Diverse Service Environments (Status: INFORMATIONAL)
RFC 4550 - Internet Email to Support Diverse Service Environments (Lemonade) Profile (Obsoleted by RFC 5550) (Status: PROPOSED STANDARD)
RFC 5383 - Deployment Considerations for Lemonade-Compliant Mobile Email (Also BCP0143) (Status: BEST CURRENT PRACTICE)
RFC 5442 - LEMONADE Architecture - Supporting Open Mobile Alliance (OMA) Mobile Email (MEM) Using Internet Mail (Status: INFORMATIONAL)
RFC 5550 - The Internet Email to Support Diverse Service Environments (Lemonade) Profile (Obsoletes RFC 4550) (Updates RFC 4469, RFC 4467) (Status: PROPOSED STANDARD)
RFC 5551 - Lemonade Notifications Architecture (Status: INFORMATIONAL)

X.400

RFC 987 - Mapping between X.400 and RFC 822 (Obsoleted by RFC 2156, RFC 1327) (Updated by RFC 1026, RFC 1138, RFC 1148) (Status: UNKNOWN)
RFC 1138 - Mapping between X.400(1988) / ISO 10021 and RFC 822 (Obsoleted by RFC 2156, RFC 1327) (Updates RFC 1026, RFC 987, RFC 822) (Updated by RFC 1148) (Status: INFORMATIONAL)
RFC 1327 - Mapping between X.400(1988) / ISO 10021 and RFC 822 (Obsoletes RFC 987, RFC 1026, RFC 1138, RFC 1148) (Obsoleted by RFC 2156) (Updates RFC 822) (Updated by RFC 1495) (Status: PROPOSED STANDARD)
RFC 1328 - X.400 1988 to 1984 downgrading (Status: HISTORIC)
RFC 1405 - Mapping between X.400(1984/1988) and Mail-11 (DECnet mail) (Obsoleted by RFC 2162) (Status: EXPERIMENTAL)
RFC 1465 - Routing Coordination for X.400 MHS Services Within a Multi Protocol / Multi Network Environment Table Format V3 for Static Routing (Status: EXPERIMENTAL)
RFC 1494 - Equivalences between 1988 X.400 and RFC-822 Message Bodies (Status: HISTORIC)
RFC 1495 - Mapping between X.400 and RFC-822 Message Bodies (Obsoleted by RFC 2156) (Updates RFC 1327) (Status: PROPOSED STANDARD)
RFC 1496 - Rules for downgrading messages from X.400/88 to X.400/84 when MIME content-types are present in the messages (Status: HISTORIC)
RFC 1502 - X.400 Use of Exten ded Character Sets (Status: HISTORIC)
RFC 1506 - A Tutorial on Gatewaying between X.400 and Internet Mail (Status: INFORMATIONAL)
RFC 1615 - Migrating from X.400(84) to X.400(88) (Status: INFORMATIONAL)
RFC 1616 - X.400(1988) for the Academic and Research Community in Europe (Status: INFORMATIONAL)
RFC 1649 - Operational Requirements for X.400 Management Domains in the GO-MHS Community (Status: INFORMATIONAL)
RFC 1685 - Writing X.400 O/R Names (Status: INFORMATIONAL)
RFC 1801 - MHS use of the X.500 Directory to support MHS Routing (Status: EXPERIMENTAL)
RFC 1838 - Use of the X.500 Directory to support mapping between X.400 and RFC 822 Addresses (Obsoleted by RFC 2164) (Status: EXPERIMENTAL)
RFC 2156 - MIXER (Mime Internet X.400 Enhanced Relay): Mapping between X.400 and RFC 822/MIME (Obsoletes RFC 987, RFC 1026, RFC 1138, RFC 1148, RFC 1327, RFC 1495) (Updates RFC 822) (Status: PROPOSED STANDARD)
RFC 2157 - Mapping between X.400 and RFC-822/MIME Message Bodies (Status: PROPOSED STANDARD)
RFC 2158 - X.400 Image Body Parts (Status: PROPOSED STANDARD)
RFC 2160 - Carrying PostScript in X.400 and MIME (Status: PROPOSED STANDARD)
RFC 2162 - MaXIM-11 - Mapping between X.400 / Internet mail and Mail-11 mail (Obsoletes RFC 1405) (Status: EXPERIMENTAL)
RFC 2163 - Using the Internet DNS to Distribute MIXER Conformant Global Address Mapping (MCGAM) (Obsoletes RFC 1664) (Updated by RFC 3597) (Status: PROPOSED STANDARD)
RFC 2164 - Use of an X.500/LDAP directory to support MIXER address mapping (Obsoletes RFC 1838) (Status: PROPOSED STANDARD)

Post Office Protocol (POP)

RFC 724 - Post Office Protocol: Version 3: Extended service offerings (Obsoleted by RFC 733) (Status: UNKNOWN)
RFC 918 - Post Office Protocol (Obsoleted by RFC 937) (Status: UNKNOWN)
RFC 937 - Post Office Protocol: Version 2 (Obsoletes RFC 918) (Status: HISTORIC)
RFC 1081 - Post Office Protocol: Version 3 (Obsoleted by RFC 1225) (Status: UNKNOWN)
RFC 1082 - Post Office Protocol: Version 3: Extended service offerings (Status: UNKNOWN)
RFC 1153 - Post Office Protocol: Version 3 (Obsoletes RFC 1081) (Obsoleted by RFC 1460) (Status: DRAFT STANDARD)
RFC 1225 - Post Office Protocol: Version 3 (Obsoletes RFC 1081) (Obsoleted by RFC 1460) (Status: DRAFT STANDARD)
RFC 1460 - Post Office Protocol: Version 3 (Obsoletes RFC 1225) (Obsoleted by RFC 1725) (Status: DRAFT STANDARD)
RFC 1725 - Post Office Protocol: Version 3 (Obsoletes RFC 1460) (Obsoleted by RFC 1939) (Status: INTERNET STANDARD)
RFC 1734 - POP3 AUTHentication command (Obsoleted by RFC 5034) (Status: PROPOSED STANDARD)
RFC 1939 - Post Office Protocol - Version 3 (Obsoletes RFC 1725) (Updated by RFC 1957, RFC 2449, RFC 6186) (Also STD0053) (Status: STANDARD)
RFC 1957 - Some Observations on Implementations of the Post Office Protocol (POP3) (Updates RFC 1939) (Status: INFORMATIONAL)
RFC 2449 - POP3 Extension Mechanism (Updates RFC 1939) (Updated by RFC 5034) (Status: PROPOSED STANDARD)
RFC 3206 - The SYS and AUTH POP Response Codes (Status: PROPOSED STANDARD)
RFC 5034 - The Post Office Protocol (POP3) Simple Authentication and Security Layer (SASL) Authentication Mechanism (Obsoletes RFC 1734) (Updates RFC 2449) (Status: PROPOSED STANDARD)
RFC 5721 - POP3 Support for UTF-8 (Status: Experimental)
RFC 6856 - Post Office Protocol Version 3 (POP3) Support for UTF-8 (Obsoletes RFC 5721) (Status: PROPOSED STANDARD)

Internet Message Access Protocol (IMAP)

RFC 1064 - Interactive Mail Access Protocol: Version 2 (Obsoleted by RFC 1176, RFC 1203) (Status: UNKNOWN)
RFC 1176 - Interactive Mail Access Protocol: Version 2 (Obsoletes RFC 1064) (Status: EXPERIMENTAL)
RFC 1203 - Interactive Mail Access Protocol: Version 3 (Obsoletes RFC 1064) (Status: HISTORIC)
RFC 1730 - Internet Message Access Protocol - Version 4 (Obsoleted by RFC 2060, RFC 2061) (Status: PROPOSED STANDARD)
RFC 1731 - IMAP4 Authentication Mechanisms (Status: PROPOSED STANDARD)
RFC 1732 - IMAP4 Compatibility with IMAP2 and IMAP2bis (Status: INFORMATIONAL)
RFC 1733 - Distributed Electronic Mail Models in IMAP4 (Status: INFORMATIONAL)
RFC 2060 - Internet Message Access Protocol - Version 4rev1 (Obsoletes RFC 1730) (Status: PROPOSED STANDARD)
RFC 2061 - IMAP4 Compatibility with IMAP2bis (Obsoletes RFC 1730) (Status: INFORMATIONAL)
RFC 2062 - Internet Message Access Protocol - Obsolete Syntax (Status: INFORMATIONAL)
RFC 2086 - IMAP4 ACL extension (Obsoleted by RFC 4314) (Status: PROPOSED STANDARD)
RFC 2087 - IMAP4 QUOTA extension (Status: PROPOSED STANDARD)
RFC 2088 - IMAP4 non-synchronizing literals (Updated by RFC 4466) (Status: PROPOSED STANDARD)
RFC 2095 - IMAP/POP AUTHorize Extension for Simple Challenge/Response (Obsoleted by RFC 2195) (Status: PROPOSED STANDARD)
RFC 2177 - IMAP4 IDLE command (Status: PROPOSED STANDARD)
RFC 2180 - IMAP4 Multi-Accessed Mailbox Practice (Status: INFORMATIONAL)
RFC 2192 - IMAP URL Scheme (Obsoleted by RFC 5092) (Status: PROPOSED STANDARD)
RFC 2193 - IMAP4 Referrals (Status: PROPOSED STANDARD)
RFC 2195 - IMAP/POP AUTHorize Extension for Simple Challenge/Response (Obsoletes RFC 2095) (Status: PROPOSED STANDARD)
RFC 2221 - IMAP4 Login Referrals (Status: PROPOSED STANDARD)
RFC 2342 - IMAP4 Namespace (Updated by RFC 4466) (Status: PROPOSED STANDARD)
RFC 2359 - IMAP4 UIDPLUS extension (Obsoleted by RFC 4315) (Status: PROPOSED STANDARD)
RFC 2683 - IMAP4 Implementation Recommendations (Updated by RFC 7162) (Status: INFORMATIONAL)
RFC 2971 - IMAP4 ID extension (Status: PROPOSED STANDARD)
RFC 3348 - The Internet Message Access Protocol (IMAP4) Child Mailbox Extension (Status: INFORMATIONAL)
RFC 3501 - INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1 (Obsoletes RFC 2060) (Updated by RFC 4466, RFC 4469, RFC 4551, RFC 5032, RFC 5182, RFC 5738, RFC 6186, RFC 6858) (Status: PROPOSED STANDARD)
RFC 3502 - Internet Message Access Protocol (IMAP) - MULTIAPPEND Extension (Updated by RFC 4466, RFC 4469) (Status: PROPOSED STANDARD)
RFC 3503 - Message Disposition Notification (MDN) profile for Internet Message Access Protocol (IMAP) (Status: PROPOSED STANDARD)
RFC 3516 - IMAP4 Binary Content Extension (Updated by RFC 4466) (Status: PROPOSED STANDARD)
RFC 3656 - The Mailbox Update (MUPDATE) Distributed Mailbox Database Protocol (Status: EXPERIMENTAL)
RFC 3691 - Internet Message Access Protocol (IMAP) UNSELECT command (Status: PROPOSED STANDARD)
RFC 4314 - IMAP4 Access Control List (ACL) Extension (Obsoletes RFC 2086) (Status: PROPOSED STANDARD)
RFC 4315 - Internet Message Access Protocol (IMAP) - UIDPLUS extension (Obsoletes RFC 2359) (Status: PROPOSED STANDARD)
RFC 4466 - Collected Extensions to IMAP4 ABNF (Updates RFC 2088, RFC 2342, RFC 3501, RFC 3502, RFC 3516) (Updated by RFC 6237, RFC 7377) (Status: PROPOSED STANDARD)
RFC 4467 - Internet Message Access Protocol (IMAP) - URLAUTH Extension (Updated by RFC 5092, RFC 5550) (Status: PROPOSED STANDARD)
RFC 4469 - Internet Message Access Protocol (IMAP) CATENATE Extension (Updates RFC 3501, RFC 3502) (Updated by RFC 5550) (Status: PROPOSED STANDARD)
RFC 4549 - Synchronization Operations for Disconnected IMAP4 Clients (Status: INFORMATIONAL)
RFC 4551 - IMAP Extension for Conditional STORE Operation or Quick Flag Changes Resynchronization (Obsoleted by RFC 7162) (Updates RFC 3501) (Status: PROPOSED STANDARD)
RFC 4731 - IMAP4 Extension to SEARCH Command for Controlling What Kind of Information Is Returned (Status: PROPOSED STANDARD)
RFC 4959 - IMAP Extension for Simple Authentication and Security Layer (SASL) Initial Client Response (Status: PROPOSED STANDARD)
RFC 4978 - The IMAP COMPRESS Extension (Status: PROPOSED STANDARD)
RFC 5092 - IMAP URL Scheme (Obsoletes RFC 2192) (Updates RFC 4467) (Updated by RFC 5593) (Status: PROPOSED STANDARD)
RFC 5161 - The IMAP ENABLE Extension (Status: PROPOSED STANDARD)
RFC 5162 - IMAP4 Extensions for Quick Mailbox Resynchronization (Obsoleted by RFC 7162) (Status: PROPOSED STANDARD)
RFC 5182 - IMAP Extension for Referencing the last SEARCH Result (Updates RFC 3501) (Status: PROPOSED STANDARD)
RFC 5255 - Internet Message Access Protocol Internationalization (Status: PROPOSED STANDARD)
RFC 5256 - Internet Message Access Protocol - SORT and THREAD Extensions (Updated by RFC 5957) (Status: PROPOSED STANDARD)
RFC 5257 - Internet Message Access Protocol - ANNOTATE Extension (Status: EXPERIMENTAL)
RFC 5258 - Internet Message Access Protocol version 4 - LIST Command Extensions (Status: PROPOSED STANDARD)
RFC 5259 - Internet Message Access Protocol - CONVERT Extension (Status: PROPOSED STANDARD)
RFC 5267 - Contexts for IMAP4 (Updated by RFC 5465) (Status: PROPOSED STANDARD)
RFC 5464 - The IMAP METADATA Extension (Status: PROPOSED STANDARD)
RFC 5465 - The IMAP NOTIFY Extension (Updates RFC 5267) (Status: PROPOSED STANDARD)
RFC 5466 - IMAP4 Extension for Named Searches (Filters) (Status: PROPOSED STANDARD)
RFC 5530 - IMAP Response Codes (Status: PROPOSED STANDARD)
RFC 5593 - Internet Message Access Protocol (IMAP) - URL Access Identifier Extension (Updates RFC 5092) (Status: PROPOSED STANDARD)
RFC 5738 - IMAP Support for UTF-8 (Updates RFC 3501) (Status: EXPERIMENTAL)
RFC 5788 - IMAP4 Keyword Registry (Status: PROPOSED STANDARD)
RFC 5819 - IMAP4 Extension for Returning STATUS Information in Extended LIST (Status: PROPOSED STANDARD)
RFC 5957 - Display-Based Address Sorting for the IMAP4 SORT Extension (Updates RFC 5256) (Status: PROPOSED STANDARD)
RFC 6154 - IMAP LIST Extension for Special-Use Mailboxes (Status: PROPOSED STANDARD)
RFC 6203 - IMAP4 Extension for Fuzzy Search (Status: PROPOSED STANDARD)
RFC 6237 - IMAP4 Multimailbox SEARCH Extension (Obsoleted by RFC 7377) (Updates RFC 4466) (Status: EXPERIMENTAL)
RFC 6851 - Internet Message Access Protocol (IMAP) - MOVE Extension (Status: PROPOSED STANDARD)
RFC 6855 - IMAP Support for UTF-8 (Obsoletes RFC 5738) (Status: PROPOSED STANDARD)
RFC 7162 - IMAP Extensions: Quick Flag Changes Resynchronization (CONDSTORE) and Quick Mailbox Resynchronization (QRESYNC) (Obsoletes RFC 4551, RFC 5162) (Updates RFC 2683) (Status: PROPOSED STANDARD)
RFC 7377 - IMAP4 Multimailbox SEARCH Extension (Obsoletes RFC 6237) (Updates RFC 4466) (Status: PROPOSED STANDARD)

Message Filtering (Sieve)

RFC 3028 - Sieve: A Mail Filtering Language (Obsoleted by RFC 5228, RFC 5429) (Status: PROPOSED STANDARD)
RFC 3431 - Sieve Extension: Relational Tests (Obsoleted by RFC 5231) (Status: PROPOSED STANDARD)
RFC 3598 - Sieve Email Filtering -- Subaddress Extension (Obsoleted by RFC 5233) (Status: PROPOSED STANDARD)
RFC 3685 - SIEVE Email Filtering: Spamtest and VirusTest Extensions (Obsoleted by RFC 5235) (Status: PROPOSED STANDARD)
RFC 3894 - Sieve Extension: Copying Without Side Effects (Status: PROPOSED STANDARD)
RFC 5173 - Sieve Email Filtering: Body Extension (Updates RFC 5229) (Status: PROPOSED STANDARD)
RFC 5183 - Sieve Email Filtering: Environment Extension (Status: PROPOSED STANDARD)
RFC 5228 - Sieve: An Email Filtering Language (Obsoletes RFC 3028) (Updated by RFC 5229. RFC 5429, RFC 6785) (Status: PROPOSED STANDARD)
RFC 5229 - Sieve Email Filtering: Variables Extension (Updates RFC 5228) (Updated by RFC 5173) (Status: PROPOSED STANDARD)
RFC 5230 - Sieve Email Filtering: Vacation Extension (Status: PROPOSED STANDARD)
RFC 5231 - Sieve Email Filtering: Relational Extension (Obsoletes RFC 3431) (Status: PROPOSED STANDARD)
RFC 5232 - Sieve Email Filtering: Imap4flags Extension (Status: PROPOSED STANDARD)
RFC 5233 - Sieve Email Filtering: Subaddress Extension (Obsoletes RFC 3598) (Status: PROPOSED STANDARD)
RFC 5235 - Sieve Email Filtering: Spamtest and Virustest Extensions (Obsoletes RFC 3685) (Status: PROPOSED STANDARD)
RFC 5260 - Sieve Email Filtering: Date and Index Extensions (Status: PROPOSED STANDARD)
RFC 5293 - Sieve Email Filtering: Editheader Extension (Status: PROPOSED STANDARD)
RFC 5429 - Sieve Email Filtering: Reject and Extended Reject Extensions (Obsoletes RFC 3028) (Updates RFC 5228) (Status: PROPOSED STANDARD)
RFC 5435 - Sieve Email Filtering: Extension for Notifications (Status: PROPOSED STANDARD)
RFC 5436 - Sieve Notification Mechanism: mailto (Updates RFC 3834) (Status: PROPOSED STANDARD)
RFC 5437 - Sieve Notification Mechanism: Extensible Messaging and Presence Protocol (XMPP) (Status: PROPOSED STANDARD)
RFC 5463 - Sieve Email Filtering: Ihave Extension (Status: PROPOSED STANDARD)
RFC 5490 - The Sieve Mail-Filtering Language -- Extensions for Checking Mailbox Status and Accessing Mailbox Metadata (Status: PROPOSED STANDARD)
RFC 5703 - Sieve Email Filtering: MIME Part Tests, Iteration, Extraction, Replacement, and Enclosure (Status: PROPOSED STANDARD)
RFC 5784 - Sieve Email Filtering: Sieve and Display Directive in XML (Status: PROPOSED STANDARD)
RFC 5804 - A Protocol for Remotely Managing Sieve Scripts (Status: PROPOSED STANDARD)
RFC 6009 - Sieve Email Filtering: Delivery Status Notifications and Deliver-By Extensions (Status: PROPOSED STANDARD)
RFC 6131 - Sieve Vacation Extension: "Seconds" Parameter (Status: PROPOSED STANDARD)
RFC 6132 - Sieve Notification Using Presence Information (Status: PROPOSED STANDARD)
RFC 6133 - Sieve Email Filtering: Use of Presence Information with Auto-Responder Functionality (Status: INFORMATIONAL)
RFC 6134 - Sieve Extension: Externally Stored Lists (Status: PROPOSED STANDARD)
RFC 6486 - Sieve Notification Mechanism: SIP MESSAGE (Status: PROPOSED STANDARD)
RFC 6558 - Sieve Extension for Converting Messages before Delivery (Status: PROPOSED STANDARD)
RFC 6609 - Sieve Email Filtering: Include Extension (Status: PROPOSED STANDARD)
RFC 6785 - Support for Internet Message Access Protocol (IMAP) Events in Sieve (Updates RFC 5228) (Status: PROPOSED STANDARD)
RFC 7352 - Sieve Email Filtering: Detecting Duplicate Deliveries (Status: PROPOSED STANDARD)

Secure Messaging

RFC 989 - Privacy enhancement for Internet electronic mail: Part I: Message encipherment and authentication procedures (Obsoleted by , RFC 1113) (Status: UNKNOWN)
RFC 1040 - Privacy enhancement for Internet electronic mail: Part I: Message enciperment and authentication procedures (Obsoletes RFC 989) (Obsoleted by RFC 1113) (Status: UNKNOWN)
RFC 1113 - Privacy enhancement for Internet electronic mail: Part I - message encipherment and authentication procedures (Obsoletes RFC 989, RFC 1040) (Obsoleted by RFC 1421) (Status: HISTORIC)
RFC 1114 - Privacy enhancement for Internet electronic mail: Part II - certificate-based key management (Obsoleted by RFC 1422) (Status: HISTORIC)
RFC 1421 - Privacy Enhancement for Internet Electronic Mail: Part I: Message Encryption and Authentication Procedures (Obsoletes RFC 1113) (Status: HISTORIC)
RFC 1422 - Privacy Enhancement for Internet Electronic Mail: Part II: Certificate-Based Key Management (Obsoletes RFC 1114) (Status: HISTORIC)
RFC 1423 - Privacy Enhancement for Internet Electronic Mail: Part III: Algorithms, Modes, and Identifiers (Obsoletes RFC 1115) (Status: EXPERIMENTAL)
RFC 1424 - Privacy Enhancement for Internet Electronic Mail: Part IV: Key Certification and Related Services (Status: HISTORIC)
RFC 1847 - Security Multiparts for MIME: Multipart/Signed and Multipart/Encrypted (Status: PROPOSED STANDARD)
RFC 2015 - MIME Security with Pretty Good Privacy (PGP) (Updated by RFC 3156) (Status: PROPOSED STANDARD)
RFC 2159 - Privacy enhancement for Internet electronic mail: Part III - algorithms, modes, and identifiers (Obsoleted by RFC 1423) (Status: HISTORIC)
RFC 2311 - S/MIME Version 2 Message Specification (Status: HISTORIC)
RFC 2312 - S/MIME Version 2 Certificate Handling (Status: HISTORIC)
RFC 2480 - Gateways and MIME Security Multiparts (Status: PROPOSED STANDARD)
RFC 2595 - Using TLS with IMAP, POP3 and ACAP (Updated by RFC 4616) (Status: PROPOSED STANDARD)
RFC 2630 - Cryptographic Message Syntax (Obsoleted by RFC 3369, RFC 3370) (Status: PROPOSED STANDARD)
RFC 2632 - S/MIME Version 3 Certificate Handling (Obsoleted by RFC 3850) (Status: PROPOSED STANDARD)
RFC 2633 - S/MIME Version 3 Message Specification (Obsoleted by RFC 3851) (Status: PROPOSED STANDARD)
RFC 2634 - Enhanced Security Services for S/MIME (Updated by RFC 5035) (Status: PROPOSED STANDARD)
RFC 3125 - Electronic Signature Policies (Status: EXPERIMENTAL)
RFC 3126 - Electronic Signature Formats for long term electronic signatures (Obsoleted by RFC 5126) (Status: INFORMATIONAL)
RFC 3156 - MIME Security with OpenPGP (Updates RFC 2015) (Status: PROPOSED STANDARD)
RFC 3335 - MIME-based Secure Peer-to-Peer Business Data Interchange over the Internet (Status: PROPOSED STANDARD)
RFC 3850 - Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.1 Certificate Handling (Obsoletes RFC 2632) (Obsoleted by RFC 5750) (Status: PROPOSED STANDARD)
RFC 3851 - Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.1 Message Specification (Obsoletes RFC 2633) (Obsoleted by RFC 5751) (Status: PROPOSED STANDARD)
RFC 3852 - Cryptographic Message Syntax (CMS) (Obsoletes RFC 3369) (Obsoleted by RFC 5652) (Updated by RFC 4853, RFC 5083) (Status: PROPOSED STANDARD)
RFC 3853 - S/MIME Advanced Encryption Standard (AES)Requirement for the Session Initiation Protocol (SIP) (Updates RFC 3261) (Status: PROPOSED STANDARD)
RFC 3854 - Securing X.400 Content with Secure/Multipurpose Internet Mail Extensions (S/MIME) (Status: PROPOSED STANDARD)
RFC 3855 - Transporting Secure/Multipurpose Internet Mail Extensions (S/MIME) Objects in X.400 (Status: PROPOSED STANDARD)
RFC 4134 - Examples of S/MIME Messages (Status: INFORMATIONAL)
RFC 4880 - OpenPGP Message Format (Obsoletes RFC 1991, RFC 2440) (Updated by RFC 5581) (Status: PROPOSED STANDARD)
RFC 5008 - Suite B in Secure/Multipurpose Internet Mail Extensions (S/MIME) (Obsoleted by RFC 6318) (Status: INFORMATIONAL)
RFC 5750 - Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.2 Certificate Handling (Obsoletes RFC 3805) (Status: PROPOSED STANDARD)
RFC 5751 - Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.2 Message Specification (Obsoletes RFC 3851) (Status: PROPOSED STANDARD)
RFC 6318 - Suite B in Secure/Multipurpose Mail Extensions (S/MIME) (Obsoletes RFC 5008) (Status: INFORMATIONAL)
RFC 6664 - S/MIME Capabilities for Public Key Definitions (Status: INFORMATIONAL)
RFC 7107 - Object Identifier Registry for the S/MIME Mail Security Working Group (Status: INFORMATIONAL)
RFC 7114 - Creation of a Registry for smime-type Parameter Values (Status: PROPOSED STANDARD)
RFC 7444 - Security Labels in Internet Email (Status: INFORMATIONAL)
RFC 7508 - Securing Header Fields with S/MIME (Status: EXPERIMENTAL)

Voice Mail

RFC 2421 - Voice Profile for Internet Mail - version 2 (Obsoletes (Obsoleted by RFC 3801) (Status: PROPOSED STANDARD)
RFC 2423 - VPIM Voice Message MIME Sub-type Registration (Obsoletes RFC 1911) (Obsoleted by RFC 3801) (Status: PROPOSED STANDARD)
RFC 2424 - Content Duration MIME Header Definition (Obsoleted by RFC 3803) (Status: PROPOSED STANDARD)
RFC 3773 - High-Level Requirements for Internet Voice Mail (Status: INFORMATIONAL)
RFC 3801 - Voice Profile for Internet Mail - version 2 (VPIMv2) (Obsoletes RFC 2421, RFC 2423) (Status: DRAFT STANDARD)
RFC 3803 - Content Duration MIME Header Definition (Obsoletes RFC 2424) (Status: DRAFT STANDARD)
RFC 3804 - Voice Profile for Internet Mail (VPIM) Addressing (Status: PROPOSED STANDARD)
RFC 4024 - Voice Messaging Client Behaviour (Status: INFORMATIONAL)
RFC 4237 - Voice Messaging Directory Service (Status: PROPOSED STANDARD)
RFC 4238 - Voice Message Routing Service (Updated by RFC 6118) (Status: PROPOSED STANDARD)
RFC 4239 - Internet Voice Messaging (IVM) (Status: PROPOSED STANDARD)

Sender Policy Framework (SPF)

RFC 4408 - Sender Policy Framework (SPF) for Authorizing Use of Domains in E-Mail (Obsoleted by RFC 7208) (Updated by RFC 6662) (Status: EXPERIMENTAL)
RFC 6577 - Authentication-Results Registration Update for Sender Policy Framework (SPF) Results (Obsoleted by RFC 7001) (Updates RFC 5451) (Status: PROPOSED STANDARD)
RFC 6652 - Sender Policy Framework (SPF) Authentication Failure Reporting Using the Abuse Reporting Format (Updates RFC 6533) (Status: PROPOSED STANDARD)
RFC 6686 - Resolution of the Sender Policy Framework (SPF) and Sender ID Experiments (Status: INFORMATIONAL)
RFC 7208 - Sender Policy Framework (SPF) for Authorizing Use of Domains in Email (Obsoletes RFC 4408) (Updated by RFC 7372) (Status: PROPOSED STANDARD)

DomainKeys (DKIM)

RFC 4686 - Analysis of Threats Motivating DomainKeys Identified Mail (DKIM) (Status: INFORMATIONAL)
RFC 4870 - Domain-Based Email Authentication Using Public Keys Advertised in the DNS (DomainKeys) (Obsoleted by RFC 4871) (Status: HISTORIC)
RFC 4871 - DomainKeys Identified Mail (DKIM) Signatures (Obsoletes RFC 4870) (Obsoleted by RFC 6376) (Updated by RFC 5672) (Status: PROPOSED STANDARD)
RFC 5016 - Requirements for a DomainKeys Identiied Mail (DKIM) Signing Practices Protocol (Status: INFORMATIONAL)
RFC 5585 - DomainKeys Identified Mail (DKIM) Service Overview (Status: INFORMATIONAL)
RFC 5617 - DomainKeys Identified Mail (DKIM) Author Domain Signing Practices (ADSP) (Status: PROPOSED STANDARD)
RFC 5672 - RFC 4871 DomainKeys Identified Mail (DKIM) Signatures -- Update (Obsoleted by RFC 6376) (Updates RFC 4871) (Status: PROPOSED STANDARD)
RFC 5863 - DomainKeys Identified Mail (DKIM) Development, Deployment, and Operations (Status: INFORMATIONAL)
RFC 6376 - DomainKeys Identified Mail (DKIM) Signatures (Obsoletes RFC 4871, RFC 5672) (Also STD0076) (Status: INTERNET STANDARD)
RFC 6377 - DomainKeys Identified Mail (DKIM) and Mailing Lists (Also BCP0167) (Status: BEST CURRENT PRACTICE)
RFC 6541 - DomainKeys Identified Mail (DKIM) Authorized Third-Party Signatures (Status: EXPERIMENTAL)
RFC 6651 - Extensions to DomainKeys Identified Mail (DKIM) for Failure Reporting (Status: PROPOSED STANDARD)

Other Anti-Spam / Malware

RFC 2505 - Anti-Spam Recommendations for SMTP MTAs (Also BCP0030) (Status: BEST CURRENT PRACTICE)
RFC 2635 - DON'T SPEW A Set of Guidelines for Mass Unsolicited Mailings and Postings (spam*) (Also FYI0035) (Status: INFORMATIONAL)
RFC 3098 - How to Advertise Responsibly Using E-Mail and Newsgroups or - how NOT to $$$$$ MAKE ENEMIES FAST! $$$$$ (Also FYI0038) (Status: INFORMATIONAL)
RFC 4095 - Attaching Meaning to Solicitation Class Keywords (Status: PROPOSED STANDARD)
RFC 4096 - Policy-Mandated Labels Such as "Adv:" in Email Subject Headers Considered Ineffective At Best (Status: INFORMATIONAL)
RFC 4406 - Sender ID: Authenticating E-Mail (Status: EXPERIMENTAL)
RFC 5782 - DNS Blacklists and Whitelists (Status: INFORMATIONAL)
RFC 6471 - Overview of Best Email DNS-Based List (DNSBL) Operational Practices (Status: INFORMATIONAL)
RFC 6647 - Email Greylisting: An Applicability Statement for SMTP (Status: PROPOSED STANDARD)
RFC 7070 - An Architecture for Reputation Reporting (Status: PROPOSED STANDARD)
RFC 7071 - A Media Type for Reputation Interchange (Status: PROPOSED STANDARD)
RFC 7072 - A Reputation Query Protocol (Status: PROPOSED STANDARD)
RFC 7073 - A Reputation Response Set for Email Identifiers (Status: PROPOSED STANDARD)
RFC 7489 - Domain-based Message Authentication, Reporting, and Conformance (DMARC) (Status: INFORMATIONAL)

Abuse Reporting

RFC 1892 - The Multipart/Report Content Type for the Reporting of Mail System Administrative Messages (Obsoleted by RFC 3462) (Status: PROPOSED STANDARD)
RFC 3462 - The Multipart/Report Content Type for the Reporting of Mail System Administrative Messages (Obsoletes RFC 1892) (Obsoleted by RFC 6522) (Updated by RFC 5337) (Status: DRAFT STANDARD)
RFC 5070 - The Incident Object Description Excange Format (Updated by RFC 6685) (Status: PROPOSED STANDARD)
RFC 5451 - Message Header Field for Indicating Message Authentication Status (Updated by RFC 6577) (Status: PROPOSED STANDARD)
RFC 5901 - Extensions to the IODEF-Document Class for Reporting Phishing (Status: PROPOSED STANDARD)
RFC 5941 - Sharing Transaction Fraud Data (Status: INFORMATIONAL)
RFC 5965 - An Extensible Format for Email Feedback Reports (Updated by RFC 6650) (Status: PROPOSED STANDARD)
RFC 6522 - The Multipart/Report Media Type for the Reporting of Mail System Administrative Messages (Obsoletes RFC 3462) (Updated by RFC 6533) (Also STD0073) (Status: INTERNET STANDARD)
RFC 6590 - Redaction of Potentially Sensitive Data from Mail Abuse Reports (Status: PROPOSED STANDARD)
RFC 6591 - Authentication Failure Reporting Using the Abuse Reporting Format (Updated by RFC 6692) (Status: PROPOSED STANDARD)
RFC 6650 - Creation and Use of Email Feedback Reports: An Applicability Statement for the Abuse Reporting Format (ARF) (Updates RFC 5965) (Status: PROPOSED STANDARD)
RFC 6684 - Guidelines and Template for Defining Extensions to the Incident Object Description Exchange Format (IODEF) (Status: INFORMATIONAL)
RFC 6430 - Email Feedback Report Type Value: not-spam (Status: PROPOSED STANDARD)
RFC 6449 - Complaint Feedback Loop Operational Recommendations (Status: INFORMATIONAL)
RFC 6577 - Authentication-Results Registration Update for Sender Policy Framework (SPF) Results (Updates RFC 5451) (Obsoleted by RFC 7001) (Status: PROPOSED STANDARD)
RFC 6591 - Authentication Failure Reporting Using the Abuse Reporting Format (Updated by RFC 6692) (Status: PROPOSED STANDARD)
RFC 6650 - Creation and Use of Email Feedback Reports: An Applicability Statement for the Abuse Reporting Format (ARF) (Updates RFC 5965) (Status: PROPOSED STANDARD)
RFC 6652 - Sender Policy Framework (SPF) Authentication Failure Reporting Using the Abuse Reporting Format (Updates RFC 4408) (Status: PROPOSED STANDARD)
RFC 6685 - Expert Review for Incident Object Description Exchange Format (IODEF)Extensions in IANA XML Registry (Updates RFC 5070) (Status: PROPOSED STANDARD)
RFC 6692 - Source Ports in Abuse Reporting Format (ARF) Reports (Updates RFC 6591) (Status: PROPOSED STANDARD)
RFC 7001 - Message Header Field for Indicating Message Authentication Status (Obsoletes RFC 5451, RFC 6577) (Obsoleted by RFC 7601) (Updated by RFC 7410) (Status: PROPOSED STANDARD)
RFC 7203 - An Incident Object Description Exchange Format (IODEF) Extension for Structured Cybersecurity Information (Status: PROPOSED STANDARD)
RFC 7372 - Email Authentication Status Codes (Updates RFC 7208) (Status: PROPOSED STANDARD)
RFC 7410 - A Property Type Registry for the Authentication-Results Header Field (Updates RFC 7001) (Obsoleted by RFC 7601) (Status: PROPOSED STANDARD)
RFC 7601 - Message Header Field for Indicating Message Authentication Status (Obsoletes RFC 7001, RFC 7410) (Status: PROPOSED STANDARD)

Other Messaging Related

RFC 974 - Mail routing and the domain system (Obsoleted by RFC 2821) (Also STD0010) (Status: HISTORIC)
RFC 1211 - Problems with the maintenance of large mailing lists (Status: INFORMATIONAL)
RFC 1339 - Remote Mail Checking Protocol (Status: EXPERIMENTAL)
RFC 1343 - A User Agent Configuration Mechanism for Multimedia Mail Format Information (Status: INFORMATIONAL)
RFC 1357 - A Format for E-mailing Bibliographic Records (Obsoleted by RFC 1807) (Status: INFORMATIONAL)
RFC 1429 - Listserv Distribute Protocol (Status: INFORMATIONAL)
RFC 1524 - A User Agent Configuration Mechanism For Multimedia Mail Format Information (Status: INFORMATIONAL)
RFC 1711 - Classifications in E-mail Routing (Status: INFORMATIONAL)
RFC 1776 - The Address is the Message (Status: INFORMATIONAL)
RFC 1807 - A Format for Bibliographic Records (Obsoletes RFC 1357) (Status: INFORMATIONAL)
RFC 1820 - Multimedia E-mail (MIME) User Agent Checklist (Obsoleted by RFC 1844) (Status: INFORMATIONAL)
RFC 1844 - Multimedia E-mail (MIME) User Agent Checklist (Obsoletes RFC 1820) (Status: INFORMATIONAL)
RFC 2142 - Mailbox Names for Common Services, Roles and Functions (Status: PROPOSED STANDARD)
RFC 2234 - Augmented BNF for Syntax Specifications: ABNF (Obsoleted by RFC 4234) (Status: PROPOSED STANDARD)
RFC 3297 - Content Negotiation for Messaging Services based on Email (Status: PROPOSED STANDARD)
RFC 3458 - Message Context for Internet Mail (Updated by RFC 3938) (Status: PROPOSED STANDARD)
RFC 3683 - A Practice for Revoking Posting Rights to IETF Mailing Lists (Also BCP0083) (Status: BEST CURRENT PRACTICE)
RFC 3834 - Recommendations for Automatic Responses to Electronic Mail (Updated by RFC 5436) (Status: PROPOSED STANDARD)
RFC 3934 - Updates to RFC 2418 Regarding the Management of IETF Mailing Lists (Updates RFC 2418) (Also BCP0025) (Status: BEST CURRENT PRACTICE)
RFC 3938 - Video-Message Message-Context (Updates RFC 3458) (Status: PROPOSED STANDARD)
RFC 4146 - Simple New Mail Notification (Status: INFORMATIONAL)
RFC 4407 - Purpoted Responsible Address in E-Mail Messages (Status: EXPERIMENTAL)
RFC 4952 - Overview and Framework for Internationalized Email (Obsoleted by RFC 6530) (Updated by RFC 5336) (Status: INFORMATIONAL)
RFC 5234 - Augmented BNF for Syntax Specifications: ABNF (Obsoletes RFC 4234) (Updated by RFC 7405) (Also STD0068) (Status: INTERNET STANDARD)
RFC 5423 - Internet Message Store Events (Status: PROPOSED STANDARD)
RFC 5598 - Internet Mail Architecture (Status: INFORMATIONAL)
RFC 5983 - Mailing Lists and Internationalized Email Addresses (Obsoleted by RFC 6783) (Status: EXPERIMENTAL)
RFC 6068 - The 'mailto' URI Scheme (Obsoletes RFC 2368) (Status: PROPOSED STANDARD)
RFC 6106 - Use of SRV Records for Locating Email Submission/Access Services (Updates RFC 1939, RFC 3501) (Status: PROPOSED STANDARD)
RFC 6186 - Use of SRV Records for Locating Email Submission/Access Services (Updates RFC 1939, RFC 3501) (Status: PROPOSED STANDARD)
RFC 6196 - Moving mailserver: URI Scheme to Historic (Updates RFC 1738) (Status: PROPOSED STANDARD)
RFC 6530 - Overview and Framework for Internationalized Email (Obsoletes RFC 4952, RFC 5504, RFC 5825) (Status: PROPOSED STANDARD)
RFC 6648 - Deprecating the "X-" Prefix and Similar Constructs in Application Protocols (Also BCP0178) (Status: BEST CURRENT PRACTICE)
RFC 6778 - Requirements for Archiving IETF Email Lists and for Providing Web-Based Browsing and Searching (Status: INFORMATIONAL)
RFC 6783 - Mailing Lists and Non-ASCII Addresses (Obsoletes RFC 5983) (Status: INFORMATIONAL)
RFC 6857 - Post-Delivery Message Downgrading for Internationalized Email Messages (Status: PROPOSED STANDARD)
RFC 6858 - Simplified POP and IMAP Downgrading for Internationalized Email (Updates RFC 3501) (Status: PROPOSED STANDARD)
RFC 7017 - IMAP Access to IETF Email List Archives (Status: INFORMATIONAL)
RFC 7103 - Advice for Safe Handling of Malformed Messages (Status: INFORMATIONAL)
RFC 7505 - A "Null MX" No Service Resource Record for Domains That Accept No Mail (Status: PROPOSED STANDARD)

Internet Fax

Note: This section covers Internet Fax standards and recommendations as they pertain to Electronic Mail and messaging in general. For additional Internet Fax resources see the Internet Telephony Resources page.

RFC 2159 - A MIME Body Part for FAX (Status: PROPOSED STANDARD)
RFC 2304 - Minimal FAX address format in Internet Mail (Obsoleted by RFC 3192) (Status: PROPOSED STANDARD)
RFC 2305 - A Simple Mode of Facsimile Using Internet Mail (Obsoleted by RFC 3965) (Status: PROPOSED STANDARD)
RFC 2306 - Tag Image File Format (TIFF) - F Profile for Facsimile (Status: INFORMATIONAL)
RFC 2531 - Content Feature Schema for Internet Fax (Obsoleted by RFC 2879) (Status: PROPOSED STANDARD)
RFC 2532 - Extended Facsimile Using Internet Mail (Status: PROPOSED STANDARD)
RFC 2534 - Media Features for Display, Print, and Fax (Status: PROPOSED STANDARD)
RFC 2542 - Terminology and Goals for Internet Fax (Status: INFORMATIONAL)
RFC 2846 - GSTN Address Element Extension in E-mail Services (Updated by RFC 3191, RFC 3192) (Status: PROPOSED STANDARD)
RFC 2879 - Content Feature Schema for Internet Fax (V2) (Obsoletes RFC 2531) (Status: PROPOSED STANDARD)
RFC 2880 - Internet Fax T.30 Feature Mapping (Status: INFORMATIONAL)
RFC 3192 - Minimal FAX address format in Internet Mail (Obsoletes RFC 2304) (Updates RFC2846) (Status: DRAFT STANDARD)
RFC 3249 - Implementers Guide for Facsimile Using Internet Mail (Status: INFORMATIONAL)
RFC 3250 - Tag Image File Format Fax eXtended (TIFF-FX) - image/tiff-fx MIME Sub-type Registration (Obsoleted by RFC 3950) (Status: PROPOSED STANDARD)
RFC 3302 - Tag Image File Format (TIFF) - image/tiff MIME Sub-type Registration (Obsoletes RFC 2302) (Status: DRAFT STANDARD)
RFC 3362 - Real-time Facsimile (T.38) - image/t38 MIME Sub-type Registration (Status: PROPOSED STANDARD)
RFC 3949 - File Format for Initernet Fax (Obsoletes RFC 2301) (Status: DRAFT STANDARD)
RFC 3950 - Tag Image File Format Fax eXtended (TIFF-FX) - image/tiff-fx MIME Sub-type Registration (Obsoletes RFC 3250) (Status: DRAFT STANDARD)
RFC 3965 - A Simple Mode of Facsimile Using Internet Mail (Obsoletes RFC 2305) (Status: DRAFT STANDARD)
RFC 4142 - Full-mode Fax Profile for Internet Mail (FFPIM) (Status: PROPOSED STANDARD)
RFC 4143 - Facsimile Using Internet Mail (IFAX) Service of ENUM (Updated by RFC 6118) (Status: PROPOSED STANDARD)
RFC 4160 - Internet Fax Gateway Requirements (Status: INFORMATIONAL)
RFC 4161 - Guidelines for Optional Services for Internet Fax Gateways (Status: INFORMATIONAL)
RFC 4612 - Real-Time Facsimile (T.38) - audio/t38 MIME Sub-type Registraton (Status: HISTORIC)

Historical Interest

RFC 196 - Mail Box Protocol (Status: UNKNOWN)
RFC 221 - Mail Box Protocol: Version 2 (Status: UNKNOWN)
RFC 224 - Comments on Mailbox Protocol (Status: UNKNOWN)
RFC 278 - Revision of the Mail Box Protocol (Obsoletes RFC 221) (Status: UNKNOWN)
RFC 458 - Mail retrieval via FTP (Status: UNKNOWN)
RFC 469 - Network mail meeting summary (Status: UNKNOWN)
RFC 475 - FTP and Network Mail System (Status: UNKNOWN)
RFC 498 - On mail service to CCN (Status: UNKNOWN)
RFC 510 - Request for network mailbox addresses (Status: UNKNOWN)
RFC 524 - Proposed Mail Protocol (Status: UNKNOWN)
RFC 539 - Thoughts on the mail protocol proposed in RFC 524 (Status: UNKNOWN)
RFC 555 - Responses to critiques of the proposed mail protocol (Status: UNKNOWN)
RFC 561 - Standardizing Network Mail Headers (Status: UNKNOWN)
RFC 574 - Announcement of a Mail Facility at UCSB (Status: UNKNOWN)
RFC 577 - Mail priority (Status: UNKNOWN)
RFC 644 - On the problem of signature authentication for network mail (Status: UNKNOWN)
RFC 706 - On the junk mail problem (Status: UNKNOWN)
RFC 720 - Address Specification Syntax for Network Mail (Status: UNKNOWN)
RFC 751 - Survey of FTP mail and MLFL (Status: UNKNOWN)
RFC 757 - Suggested solution to the naming, addressing, and delivery problem for ARPANET message systems (Status: UNKNOWN)
RFC 763 - Role mailboxes (Status: UNKNOWN)
RFC 767 - Structured format for transmission of multi-media documents (Status: UNKNOWN)
RFC 771 - Mail transition plan (Status: UNKNOWN)
RFC 772 - Mail Transfer Protocol (Obsoleted by RFC 780) (Status: UNKNOWN)
RFC 773 - Comments on NCP/TCP mail service transition strategy (Status: UNKNOWN)
RFC 780 - Mail Transfer Protocol (Obsoletes RFC 772) (Obsoleted by RFC 788) (Status: UNKNOWN)
RFC 784 - Mail Transfer Protocol: ISI TOPS20 implementation (Status: UNKNOWN)
RFC 785 - Mail Transfer Protocol: ISI TOPS20 file definitions (Status: UNKNOWN)
RFC 786 - Mail Transfer Protocol: ISI TOPS20 MTP-NIMAIL interface (Status: UNKNOWN)
RFC 805 - Computer mail meeting notes (Status: UNKNOWN)
RFC 806 - Proposed Federal Information Processing Standard: Specification for message format for computer based message systems (Obsoleted by RFC 841) (Status: UNKNOWN)
RFC 807 - Multimedia mail meeting notes (Status: UNKNOWN)
RFC 808 - Summary of computer mail services meeting held at BBN on 10 January 1979 (Status: UNKNOWN)
RFC 841 - Specification for message format for Computer Based Message Systems, National Bureau of Standards (Obsoletes RFC 806) (Status: UNKNOWN)
RFC 876 - Survey of SMTP implementations (Status: UNKNOWN)
RFC 910 - Multimedia mail meeting notes (Status: UNKNOWN)
RFC 915 - Network mail path service (Status: UNKNOWN)
RFC 976 - UUCP mail interchange format standard (Updated by RFC 1137) (Status: UNKNOWN)
RFC 984 - PCMAIL: A distributed mail system for personal computers (Obsoleted by RFC 993) (Status: UNKNOWN)
RFC 993 - PCMAIL: A distributed mail system for personal computers (Obsoletes RFC 984) (Obsoleted by RFC 1056) (Status: UNKNOWN)
RFC 1056 - PCMAIL: A distributed mail system for personal computers (Obsoletes RFC 993) (Status: INFORMATIONAL)
RFC 1137 - Mapping between full RFC 822 and RFC 822 with restricted encoding (Updates RFC 976) (Status: HISTORIC)
RFC 1168 - Intermail and Commercial Mail Relay services (Status: INFORMATIONAL)
RFC 4417 - Report of the 2004 IAB Messaging Workshop (Status: INFORMATIONAL)

Tim's Place