SMTP is a protocol used to send and receive emails.
SMTP is the acronym that corresponds to the expression of the English language Simple Mail Transfer Protocol . In our language , this concept can be translated as Simple Mail Transfer Protocol .
SMTP is a network protocol used to send and receive electronic mail ( emails ). It should be noted that a network protocol is a set of regulations and rules that enable the circulation of information in a computer network . In this case, SMTP is part of the so-called Internet protocols .
SMTP operation occurs in the context of email services. Due to certain technical restrictions for receiving emails, it is common for SMTP to be used only for sending messages and for reception to use other Internet protocols, such as IMAP ( Internet Message Access Protocol ) or POP ( Post Office Protocol). ).
SMTP function
In the case of SMTP , its function is to allow a client to communicate with a server , allowing the client to send an email to one or more recipients . SMTP works with lines of text to provide the necessary instructions.
There are three commands that make up SMTP: MAIL , which sets the sender address for goodbye messages; RCPT , which establishes the recipient of the message (if there are several, it is issued once for each one); DATA , command that sends the content of the message.
When a person sends an email through this protocol , what happens is that the email client (such as Outlook Express or Mozilla Thunderbird ) presents the message in question to a mail server through SMTP . The server sends the message to the Mail Transfer Agent ( MTA ), which appeals to the Domain Name System ( DNS ) to look up the MX record . When it accepts the mail, it in turn forwards it to a Mail Delivery Agent ( MDA ), which can again use SMTP to deliver it to the mail server. Using IMAP , finally, the receiving user can retrieve the message in their email client.
The server sends responses whose content is nothing more than a code composed of three numbers and then an explanatory text: the first component is used for the PLC response; The text, for its part, is directed at a user, so that they are able to understand the answer. Each replica, data or order belonging to the SMTP protocol is made up of lines of text that are delimited with the character
SMTP is the acronym for Simple Mail Transfer Protocol.
Your story
While the Internet did not become mainstream until the late 1990s, virtual exchanges began several years earlier. With respect to email, the first exchange system appeared in 1982 , which existed in the network called ARPANET , used by the United States Department of Defense so that state and academic institutions could communicate with each other. This system is defined in RFC 821 and 822 (the acronym for Request for comments , publications in which descriptions of various procedures and protocols related to computer networks appear, among which the Internet stands out).
The SMTP defined in the first version of email was based on the client-server model , which establishes that the client sends a message to one or more recipients. The content of said communication is made up solely of lines of text, made up of ASCII characters, with a maximum length of one thousand characters each. It should be noted that the acronym ASCII comes from American Standard Code for Information Interchange , which is translated as American Standard Code for Information Interchange, and is a series of characters from the Latin alphabet; Its most common pronunciation, although it is not easy to deduce, is [asqui].