Panix Help System: Why we recommend IMAP

The preferred modern method of connecting to mailservers is IMAP ("Internet Message Access Protocol"), as opposed to POP ("Post Office Protocol"), which you may have been using up until now. IMAP is far better suited to the modern assumption of persistent network connections (whether wired or not), of abundant server-side diskspace, and to the increasing ubiquity of handheld and portable network access devices (e.g. netbooks, smartphones, etc.).

IMAP works by essentially turning the mail client into a terminal or browser continuously connected to the mailserver. The mail itself does not get downloaded (unless the client is specifically instructed to transfer messages from the remote server into a local folder); only the headers do. The benefits are:

Some historical context for POP:

Up until relatively recently, the prevailing of retrieving mail using what used to be called an "offline mail client" (such as Outlook, Thunderbird, and their ilk) was the "Post Office Protocol," or "POP". POP would form a temporary connection with a mailserver, download all the mail in one batch, delete it from the server, and disconnect. Mail could then be read while the local machine was offline (hence the earlier terminology).

This was the favored method when the common conditions included a) limited availability of diskspace on shared mailservers and b) non-persistent dialup connections (usually tying up a voice line).

There were (and are) several disadvantages to POP:

For these reasons, we strongly advise switching to IMAP.

Last Modified:Wednesday, 30-Jan-2013 12:14:13 EST
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