Post Office Protocol

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Post Office Protocol

[¦pōst ‚ȯf·əs ′prōd·ə‚ku̇l]
(computer science)
An Internet standard for delivering e-mail from a server to an e-mail client on a personal computer. Abbreviated POP.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

Post Office Protocol

(messaging, protocol)
(POP) A protocol designed to allow single-user computers to retrieve electronic mail from a POP server via TCP/IP. The default port is 110.

The POP server might be a computer with a permanent Internet connection whereas its clients might only connect to it occasionally, e.g. by modem.

There are (in 1994) three versions: POP, POP2, and POP3. Later versions are NOT compatible with earlier ones.

This article is provided by FOLDOC - Free Online Dictionary of Computing (


(Post Office Protocol 3) A programming interface (API) from the IETF that enables a user's email program to access the mail server (RFC 1939 standard). Email clients such as Outlook, Mail, Eudora and Thunderbird are typically configured to retrieve mail either via POP3 or IMAP4, the other popular standard.

POP3 is a simple system with limited selectivity. Incoming messages and attachments are downloaded when users check their mail, and POP is typically configured to delete the messages on the server after downloading. If the user opts to not delete them, the messages will download again the next time mail is checked. See IMAP4, email interfaces, SMTP and messaging system.

Incoming Mail Options
Most Internet mail services offer all three options. Users may choose IMAP if they need access from several computers or if they like to keep mail online indefinitely (see IMAP4).
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References in periodicals archive ?
Using JavaScript objects and commands the Productivity Pack can load and verify application performance and scalability for a range of protocols, including the File Transfer Protocol (FTP), Simple Mail Transfer Protocol (SMTP) and Post Office Protocol 3 (POP3).
The IETF created IMAP to address the limitations of post office protocol (POP), an Internet mail standard that fell short in answering all the questions associated with delivering e-mail to disconnected clients.
In pure Internet email systems, the MTA works in conjunction with delivery agents such as a Post Office Protocol (POP) or Internet Message Access Protocol (IMAP) servers.
-- The Simple Mail Transfer Protocol (SMTP), Hypertext Transfer Protocol (HTTP) and Post Office Protocol (POP3)
The packets are then reassembled in the proper sequence and presented to Bob in a readable format either in SMTP (Simple Mail Transfer Protocol), POP (Post Office Protocol) or IMAP (Internet Message Access Protocol).
The two companies hope to release a product next year which will combine Sendmail's support for simple mail transfer protocol (SMTP) with MessagingDirect's implementations of post office protocol (POP3) and internet mail access protocol (IMAP4).
* Post Office Protocol (POP) server, which allows you to run your mail program and handle your mail on your computer, lowering connect time.
-- Extensive Standards Support -- Support for Internet protocols such as Post Office Protocol 3 (POP), Internet Mail Access Protocol 4 (IMAP), Lightweight Directory Access Protocol (LDAP) and Secure Sockets Layer (SSL)
Standards, such as simple mail transport protocol (SMTP), post office protocol (POP) and Internet message access protocol (IMAP), were created and incorporated into the Internet, as well as integrated into other messaging platforms based on client-server technology.

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