IMAP vs. POP

The University's email servers (Equinox, Exchange, and Fallon) support two ways to store messages. When you configure your email client software (e.g., Netscape, MS Explorer, Eudora, etc.), you need to select one of the two types. We recommend IMAP over POP. The following describes advantages and disadvantages of the two protocols:

Internet Message Access Protocol (IMAP)

Advantages:

  • Your email stays on your server, saving local (PC/Mac) disk space.
  • Your email resides on a server that is administered by a professional, is not susceptible to hardware failure, and is backed up to tape on a regular schedule.
  • You always have access to an updated mailbox and you can get your email from any Internet-ready computer.
  • Performance on a dial-up modem is faster since you initially download only the message headers.
  • You can synchronize specific mail folder for offline use.
  • You can define multiple IMAP mail servers (different email accounts).

Disadvantages:

  • Since all messages are kept on the server, you need to be aware of server disk-storage quotas.
  • Connect time could be longer since you must be connected while you are browsing your messages or reconnect every time you access a message you haven't read.

Post Office Protocol (POP)

Advantages:

  • Your messages are downloaded to your local computer, releasing server disk space and making offline reading easier.
  • Many commercial servers depend on POP to serve email, so it may be the only choice.

Disadvantages:

  • Since POP3 downloads complete copies of each email, download times may be VERY long, especially for messages containing large attachments (documents or images).
  • You must synchronize your local InBox with the server's mailbox. This can result in downloading new messages over and over each time you connect.
  • If you choose to configure POP3 to download all files and if you use more than one computer, messages might reside on one or the other, but not both computers.
  • POP3 can be configured to leave a copy of each message on the server, thus making it accessible from everywhere and giving you an inherent backup scheme. (However, server disk space and quotas become issues.)
  • If you do not leave a copy of each message on the server, you are responsible for backing it up and restoring email should you need to recover a deleted item or have a hardware failure.
  • POP3 doesn't work as efficiently as IMAP over a slow connection (dial-up modem).
  • Only one email address may be configured.