IMAP, POP and SMTP ProtocolsThese are  three different methods or protocols used to handle email. The are used to either receive (IMAP, POP) or send (SMTP) email.Receiving email – a simple overviewWhen someone sends you an email it moves from their email client to their mail server. Their mail server then uses the recipient email address to determine where the mail is supposed to go and delivers the email to your mail server.These two mail servers may exists as part of a hosting package, be provided by their ISP or be a paid for free 3rd party mail service and can even be the same server. They can be around the world or in the same building where you work.Your mail server stores the received email in a mailbox until your mail client asks for it. This is where IMAP and POP enter the picture.IMAP (Internet Message Access Protocol) and POP (Post Office Protocol)IMAP and POP are the two most prevailing methods or protocols for retrieving email from a mail server. Both of these protocols are supported by almost all popular mail client programs like Outlook, Thunderbird and Apple Mail.When your mail client reads an email it can either download the email from the mail server to your local desktop and delete it from the mail server, or just allow you to see the email contents, without saving it locally, similar to your viewing a webpage. In the first case, where you download an email to your local machine, POP is used. In the second case, where you view the email, it actually stays on the mail server.Main differencesPOP – Downloads email locallyIMAP – Mail is stored on the mail server Benefits and disadvantagesThere as benefits and disadvantages to using either protocol.

POP

Benefits Disadvantages

Mail is stored locally you can access it when offline

Need to use workaround to read email on multiple machines

Easier to maintain mail quotas All mail can be lost if your

hard drive or computer dies and you don’t have a backup

Easy to backup and archive locally or offsite

Harder to access mail anywhere

Faster – only need to read mail from server once

Faster when you have to search email

 

IMAP

Benefits Disadvantages

Mail is stored remotely, you can access anywhere

Takes up a lot of server space – may easily exceed your quota **

Keeps a copy of everything you do on the mail server. Privacy concerns may apply.

All mail can be lost if your hard drive or computer dies and you don’t have a backup

Easy to backup and archive locally or offsite

Slower in reading email – index of all messages downloaded

Faster – only need to read mail from server once

Harder to backup locally and remotely.

Faster when you have to search email

All mail can be lost if mail account becomes corrupted, server crashes and backup is bad

Slow when searching email – all emails are downloaded and read by mail client.

 RecommendationsIn almost all cases we recommend that our customers use POP for reading their email. Sending EmailsIn either case, POP or IMAP, when you send an email you will use some form of SMTP (Simple Mail Transfer Protocol), which totally different from IMAP and POP. 

When you click on send on an email message the mail client contacts the SMTP server that is part of your mail service. The server authenticates you using your login id and password and receives the email message from your client. The mail server then looks up the recipient’s mail server and passes the message to that server. Your mail client then places the sent email in either your local sent mail folder or in the case of IMAP the sent email folder on the server. ** Benefits of Hosted Exchange ServerOur unlimited Hosted Exchange Service works similar to IMAP in that you keep all your messages on the mail server. It overcomes the quota limitations as well as the offline reading of email, when used with the latest version of Outlook (free with Hosted Exchange). You can also share a mailbox and allow others to send email on your behalf.If you want large mailbox quotas, need to share a mailbox or want to be able to read email anywhere then we highly recommend moving to our Hosted Exchange Service.