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Simple Mail Transfer Protocol

The Simple Mail Transfer Protocol (SMTP) is an Internet standard communication protocol for electronic mail transmission. Mail servers and other message transfer agents use SMTP to send and receive mail messages. User-level email clients typically use SMTP only for sending messages to a mail server for relaying, and typically submit outgoing email to the…

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Abbreviation
SMTP
Introduction
November 1981; 44 years ago (1981-11)
OSI layer
Application layer
Ports
465, 587, 25
Purpose
Electronic mail transmission protocol

Topics to explore

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Overview

History

Mail processing model

Protocol overview

Outgoing mail SMTP server

SMTP transport example

SMTP Extensions

Spoofing and spamming

Advanced semantic analysis

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Map overview Semantic statistics

Simple Mail Transfer Protocol

Nodes157
Edges156
Triples114
Avg. degree1.99
Density0.012739
Components1

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Simple Mail Transfer Protocol

Top relations

related to Further reading · 55
Simple Mail Transfer Protocol → Access, Accountability Requirements, An Extensible Message Format, Anti-Spam Recommendations, Application, Authentication, Automatic Responses, BCP, Binary MIME MessagesRFC, Cleartext Considered Obsolete, Command Pipelining, Delivery Status Notifications, Downgrading Mechanism, Electronic MailRFC, Email Address InternationalizationRFC, Email Submission, Email Submission Operations, Enhanced Status Codes, Framework, Internationalized Email
related to Modern SMTP · 15
Simple Mail Transfer Protocol → As, But, Cleanly, ESMTP, Extended Simple Mail Transfer, In November, Message, Originally, Protocol, RFC, SMTP, SMTP-AUTH, This, Work, World Wide Web
related to Original SMTP · 13
Simple Mail Transfer Protocol → FTP, IANA, In, In November, Mail Transfer Protocol, May, Postel, RFC, Suzanne Sluizer, TCP, The SMTP, UDP, Usenet
related to External links · 10
Simple Mail Transfer Protocol → Authentication, ESMTPA, LMTP Transmission Types Registration, Mail, Message Submission, RFC, Simple Mail Transfer ProtocolRFC, SMTP, SMTP Service Extension, SMTP Service ExtensionsRFC
Abbreviation · 1
Simple Mail Transfer Protocol → SMTP
Introduction · 1
Simple Mail Transfer Protocol → November 1981; 44 years ago (1981-11)
OSI layer · 1
Simple Mail Transfer Protocol → Application layer
Ports · 1
Simple Mail Transfer Protocol → 465, 587, 25
Purpose · 1
Simple Mail Transfer Protocol → Electronic mail transmission protocol
RFC · 1
Simple Mail Transfer Protocol → .mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:r…

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Important terminology

server smtp mail message rfc email protocol use servers transfer client internet clients messages used address authentication may submission using

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Simple Mail Transfer ProtocolAbbreviationSMTP1.00infobox
Simple Mail Transfer ProtocolIntroductionNovember 1981; 44 years ago (1981-11)1.00infobox
Simple Mail Transfer ProtocolOSI layerApplication layer1.00infobox
Simple Mail Transfer ProtocolPorts465, 587, 251.00infobox
Simple Mail Transfer ProtocolPurposeElectronic mail transmission protocol1.00infobox
Simple Mail Transfer ProtocolRFC.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:r…1.00infobox
relaying of unsolicited emailinstance ofmeant that SMTP had to include specific rules and methods for relaying mail and authenticating users to prevent abuses0.80text
Multipurpose Internet Mail Extensionsinstance ofStandards0.80text
Local Mail Transfer Protocolinstance ofor forward them over a network using SMTP or other protocol0.80text
Microsoft Exchange/Outlook or Lotus Notes/Dominoinstance ofwhich typically uses the traditional mbox mail file format or a proprietary system0.80text
universities which provided an SMTP server for outbound mail only for use internally within the organisationinstance ofThese methods were typically used by corporations and institutions0.80text
Greekinstance ofsuch as those with diacritics and other language characters0.80text

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