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SMTP

Network and Internet Systems

SMTP, the Simple Mail Transfer Protocol, is the Internet standard protocol mail servers and other message transfer agents use to send and receive electronic mail, first specified in RFC 788 in November 1981 with major input from Jon Postel. It defines how one mail server hands a message to another across a network, and it remains the protocol that carries mail between servers today even though separate protocols such as POP3 and IMAP handle a mailbox's retrieval by an end-user client. SMTP has been revised several times, most significantly in RFC 5321, while keeping its original command-and-response design. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Year
1981 1
Significance
The Internet standard protocol mail servers use to transmit electronic mail between systems. 1
Status
Status
Active / In Use 1
FAQs

Does SMTP deliver mail to my inbox?

SMTP moves mail between servers; POP3 and IMAP are what let you read it.

Not by itself. SMTP is the protocol that transfers mail between servers, passing a message along through relay hosts until it reaches its destination mail system. Reading mail from a mailbox on your phone or computer is handled by separate protocols such as POP3 and IMAP. Mail programs commonly use SMTP only for sending, as a submission step, although the standard notes that a separate mail submission protocol is now preferred to direct use of SMTP.
Connections

Associated With

Jon Postel, Pioneers

In Field

Invented By

Jon Postel, Pioneers
Source Programming Language Database (PLDB): SMTP
Sources
1. Wikipedia: SMTP
Wikimedia Foundation
  • Lead section
    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.
  • Lead sentence
    Simple Mail Transfer Protocol (SMTP) is an Internet standard communication protocol for electronic mail transmission.
  • In Group: Internet Application Protocols, Lead
    The Simple Mail Transfer Protocol (SMTP) is an Internet standard communication protocol for electronic mail transmission.
View the Source
Wikidata: Simple Mail Transfer Protocol
Wikidata Q160453, resolved via en.wikipedia pageprops (wave rule R-L)View the Source
Programming Language Database (PLDB): SMTP
Programming Language Database (PLDB)Invented By: Jon Postel, Page lead
Quote, Invented By: Jon Postel, Page lead
created in 1982 by Jon Postel
View the Source
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