P.O.P. A presentation brought to you by Thomas
Topics Introduction General Information Area of use Functionality The alternative way POP3 vs. IMAP Conclusion
What is POP Post Office Protocol Actual Version is POP3 Responsible for recieving s from a mailserver Most widely implemented protocol for retrieval of Internet Mail
General information Standard Port for POP3 is 110 Session – Layer Platform independent RFC service provider need to install a POP3 server for offering POP. POP3 transferred s are secured by SSL or TLS
Area of use Supported by most mail client applications TCP/IP Networks Free internet mail services -...but mostly IMAP is provided on a higher service level
How does it work -XXX indicates the user who is registered at the webdomain YYY.ZZ -The user logs in to the webdomain via client. Password and account will be checked. -If validation is correct, POP3 of the client requests download of new mails.
How does it work II POPserver of mail provider accepts the request, if there are no problems. Download will be initialized by mail client application. All mails could be deleted from the mailbox on mailserver. (optional) After download connection will be closed again.
For the one without mail client... Via telnet direct connection to mailbox using POP (PlainTextLogin). Commands: USER Login LIST shows the content of mailbox RETR downloads selected mail DELE deletes selected mail QUIT Closes connection from hostside
telnet pop.gmx.net 110 Trying Connected to pop.gmx.net. Escape character is ‚^C]'. +OK GMX POP3 StreamProxy ready USER +OK May I have your password, please? +OK mailbox has 3 messages (5985 octets) Login procedure
LIST +OK mailbox has 3 messages (5985 octets) RETR 1 +OK message follows Return-Path: X-Flags: 0000 Delivered-To: GMX delivery to (MAIL) checkmail procedure
...(MAIL END) DELE 1 +OK message deleted QUIT +OK bye Connection closed by foreign host. Delete/Logout procedure
POP3 vs. IMAP IMAP is suitable for online access to a mailbox service, where messages are stored and filed on a permanent or semi-permanent basis on the server. POP3 is suitable for a mailbox service, where messages are only stored for a temporary period on the server. POP3 is less complex. Generally IMAP is used in companies, POP is used by private users.
Conclusion Everyone who plans to implement an system should think about using IMAP or POP3, depending on his needs. Easy and fast working. For private use adequate, but companies with bigger mailing systems should use IMAP.
Thank you for your attention......any questions?