{"id":2022,"date":"2012-02-27T11:21:02","date_gmt":"2012-02-27T11:21:02","guid":{"rendered":"https:\/\/www.techopedia.com\/definition\/simple-mail-transfer-protocol\/"},"modified":"2017-01-17T14:26:26","modified_gmt":"2017-01-17T14:26:26","slug":"simple-mail-transfer-protocol","status":"publish","type":"definition","link":"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp","title":{"rendered":"Simple Mail Transfer Protocol"},"content":{"rendered":"

What Does Simple Mail Transfer Protocol Mean?<\/span><\/h2>\n

Simple Mail Transfer Protocol (SMTP) is the standard protocol for email services on a TCP\/IP network. SMTP provides the ability to send and receive email messages.\n<\/p>\n

SMTP is an application-layer protocol that enables the transmission and delivery of email over the Internet. SMTP is created and maintained by the Internet Engineering Task Force (IETF).\n<\/p>\n

Simple Mail Transfer Protocol is also known as RFC 821 and RFC 2821.\n<\/p>\n

Techopedia Explains Simple Mail Transfer Protocol<\/span><\/h2>\n

SMTP is one of the most common and popular protocols for email communication over the Internet and it provides intermediary network services between the remote email provider or organizational email server and the local user accessing it.\n<\/p>\n

SMTP is generally integrated within an email client application and is composed of four key components:\n<\/p>\n

    \n
  1. Local user or client-end utility known as the mail user agent (MUA)<\/li>\n
  2. Server known as mail submission agent (MSA)<\/li>\n
  3. Mail transfer agent (MTA)<\/li>\n
  4. Mail delivery agent (MDA)<\/li>\n<\/ol>\n

    SMTP works by initiating a session between the user and server, whereas MTA and MDA provide domain searching and local delivery services.<\/p>\n","protected":false},"excerpt":{"rendered":"

    What Does Simple Mail Transfer Protocol Mean? Simple Mail Transfer Protocol (SMTP) is the standard protocol for email services on a TCP\/IP network. SMTP provides the ability to send and receive email messages. SMTP is an application-layer protocol that enables the transmission and delivery of email over the Internet. SMTP is created and maintained by […]<\/p>\n","protected":false},"author":7813,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","format":"standard","meta":{"_acf_changed":false,"_lmt_disableupdate":"","_lmt_disable":"","om_disable_all_campaigns":false,"footnotes":""},"definitioncat":[245],"class_list":["post-2022","definition","type-definition","status-publish","format-standard","hentry","definitioncat-internet"],"acf":[],"yoast_head":"\nWhat is Simple Mail Transfer Protocol (SMTP)? - Definition from Techopedia<\/title>\n<meta name=\"description\" content=\"This definition explains the meaning of Simple Mail Transfer Protocol and why it matters.\" \/>\n<meta name=\"robots\" content=\"noindex, follow\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Simple Mail Transfer Protocol\" \/>\n<meta property=\"og:description\" content=\"This definition explains the meaning of Simple Mail Transfer Protocol and why it matters.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp\" \/>\n<meta property=\"og:site_name\" content=\"Techopedia\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/techopedia\/\" \/>\n<meta property=\"article:modified_time\" content=\"2017-01-17T14:26:26+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:site\" content=\"@techopedia\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp#article\",\"isPartOf\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp\"},\"author\":{\"name\":\"Margaret Rouse\",\"@id\":\"https:\/\/www.techopedia.com\/#\/schema\/person\/f5dd538e31ee352d105b8af36c4268a5\"},\"headline\":\"Simple Mail Transfer Protocol\",\"datePublished\":\"2012-02-27T11:21:02+00:00\",\"dateModified\":\"2017-01-17T14:26:26+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp\"},\"wordCount\":185,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\/\/www.techopedia.com\/#organization\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp#respond\"]}],\"articleSection\":\"\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp\",\"url\":\"https:\/\/www.techopedia.com\/definition\/1710\/simple-mail-transfer-protocol-smtp\",\"name\":\"What is Simple Mail Transfer Protocol (SMTP)? 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