SMTP Vs POP

SMTP and POP are the two most widely used mailing protocols over the Internet.

SMTP is a simple text based protocol where one or more recipients are specified and message is transferred. SMTP server can be tested easily through a telnet. Today, most SMTP servers support the 8BITMIME extension, permitting binary files to be transmitted almost as easily as plain text. One of the prevalent disadvantages is that it doesn’t authorize users so there arose a need to define SMTP-AUTH.

POP is another mailing system used by email clients. These days it’s the version 3 which is used known as POP3 (version 3). Basically, users read their mails from a client software provided by ISPs that uses POP3.

NOTE : The server assigns a string of characters as a permanent and unique ID for the message. When a POP3-compatible e-mail client connects to the server, it can use the UIDL command to get the current mapping from these message IDs to the ordinal message numbers. The client can then use this mapping to determine which messages it has yet to download, which saves time when downloading.

One of the most silly and inane problems of users who use a CMS on their website is related to SMTP & POP. I often get mails or sometimes people themselves asking me that whenever a user registers on his website, he never receives the welcome mail. Suppose a user forgets his password. He tries to recover it by clicking the “forgot password” link or button whatever the case may be. The remarkable thing is that he never gets that mail containing the password. So it is obvious that the mail is never sent from the site using that CMS.

The problem lies at the very core of the settings in the CMS. Mostly a CMS switched to POP is never able to send the mail (also depends on the server facility). So please switch it to SMTP and the things work absolutely fine.

SMTP : Simple Mail Transfer Protocol
CMS : Content Management System
POP : Post Office Protocol