POP – IMAP – SMTP a Basic explanation August 7, 2010Posted by Tournas Dimitrios in Uncategorized.
Did you know that when someone sends you an email, it doesn’t arrive directly at your computer? The message first comes to a computer that’s connected to the internet 24/7 and is stored there. Such a computer is known as a web server and to receive email messages it runs a special program called the email server. Depending on the kind of access allowed, you can check your emails using a web browser or employ a dedicated email program (also known as an email client).
Email clients are programs that let you send and receive email messages from your computer. There are several popular free email clients like Outlook Express, Windows Mail Vista, Windows Live Mail and Thunderbird. If you use Windows, you already have an email program pre-installed on your system – Outlook Express on Windows XP and Windows Mail on Vista. Some time back Microsoft released a new email client which they call Windows Live Mail meant to “replace” Outlook Express and Windows Mail Vista .
Importance and usage of POP :
The POP technology is used to build a communication channel between an email client and a server. It sets rules for downloading email messages that are stored on an online hard disk to your local computer hard disk. Using POP you can download all emails to your computer and, thus, view them anywhere you want – even without an internet connection. Yes, an active internet line is required to download messages from the server but once they come to your computer, you can sever the connection.
You’ll appreciate the importance of POP if you have ever faced a problem in accessing email messages (even the old ones) from an online account such as Hotmail, Yahoo! Mail or Gmail. Maybe the net connection wasn’t working properly, maybe you were at a location where internet wasn’t available or maybe the email service was down… whatever. And frustration is what follows.
Now imagine the brighter scenario of keeping a copy of all your emails on your computer using a using POP enabled email program. Agreed you’ll still not be able to check for new messages but you at least have access to old ones.
Do all email servers use POP?
No – it depends on the service provider and the web server configuration. Typically, email accounts from ISPs (Internet Service Providers) and those you create on your web site come with POP access. Online email service providers like Yahoo! Mail, Hotmail, AOL and Gmail have different policies when it comes to POP access. For instance, you can enable POP on Gmail accounts for free – you can do this yourself. Yahoo! Mail charges you about $20 per year access your account through POP. For Windows Live Hotmail users, there is some good news finally; POP on Hotmail is gradually being rolled out – it’s available only to subscribers in some countries at the time of writing and I hope it will soon be included on all accounts.
Why don’t all email services allow POP access?
Well, since the protocol lets you to download messages to your computer via an email client, you’ll have no need to checking your messages on the web based service. This means you would hardly ever log in to your online account and, thus, would not “pay” for your free access by either looking at the advertisements or, less so, clicking on them! All free web based email accounts, even Gmail, are supported by the advertising. The companies show these ads expecting subscribers to compensate the privilege of free access by checking out the sponsored products or services.
How do you access email through POP – Post Office Protocol?
As mentioned above, your email service should provide you with a POP access. Please check with them. Once you get a POP enabled email account, all you need is an email client that can use the Post Office Protocol. Windows users are lucky because a free email client is available on all versions. In fact, Microsoft has released the new Windows Live Mail email client which can be downloaded for free from their web site.
Accessing emails through POP is a simple affair. You only need the username, password and the email server address. The incoming email server address is, typically, pop.THE-DOMAIN-NAME.com or simply THE-DOMAIN-NAME.com. For step by step instructions on using POP with Windows Outlook Express email client please refer here >>>
The Post Office Protocol is employed only for downloading emails and goes hand in hand with SMTP or the Simple Mail Transfer Protocol which is used for sending emails.
POP enabled email account can also be accessed via a web browser as long as the service provider has put up an interface (a graphical user interface, usually) through which the account can be managed.
What is SMTP?
When someone sends you an email, it’s transferred over the internet from one server to another using SMTP. When the message finally arrives at your email server, you can download it to your computer using an email client employing the Post Office Protocol.
The main function of text based SMTP protocol is to “push” emails – it cannot “pull” them from servers which is why you also need POP. The “outgoing” mail server protocol helps servers communicate with each other and facilitate the delivery of the email message.
SMTP functions in two ways. Firstly, it verifies the configuration of the computer from where the email is being sent and grants permission for the process. Secondly, it sends out the message and follows the successful delivery of the email. If the email cannot be delivered, it’s returned-to-sender or bounces back.
The enhanced version of SMTP called Extended SMPT or (ESMTP) is employed for sending images and other file attachments along with emails.
SMTP and spamming :
Since SMTP does not authenticate the sender, it has been exploited for sending spam. And because of this, most ISPs keep a close check on the number of outgoing email messages from each account. In fact, ISP generally do not allow account holders to send email from other SMTP address but their own and they do this by quickly blocking ports 25 (and/or 26). This leads to the most common complain – cannot send emails – from subscribers who configure a non ISP email account, such as those from their web sites or web based email providers, in a email client. The problem can usually be ironed out by contacting the ISP and asking for their SMPT outgoing server address, port number and authentication information.
What is IMAP?
IMAP, or Internet Message Access Protocol, lets you download messages from Gmail’s servers onto your computer so you can access your mail with a program like Microsoft Outlook Express or Apple Mail, even when you aren’t connected to the Internet.
IMAP creates a constant connection between mail clients (desktop and/or mobile) and Gmail.
What’s the difference between IMAP and POP?
Unlike POP, IMAP offers two-way communication between your web Gmail and your email client(s). This means when you log in to Gmail using a web browser, actions you perform on email clients and mobile devices (ex: putting mail in a ‘work’ folder) will instantly and automatically appear in Gmail (ex: it will already have a ‘work’ label on that email the next time you sign in).
IMAP also provides a better method to access your mail from multiple devices. If you check your email at work, on your mobile phone, and again at home, IMAP ensures that new mail is accessible from any device at any given time.
Finally, IMAP offers a more stable experience overall. Whereas POP is prone to losing messages or downloading the same messages multiple times, IMAP avoids this through two-way syncing capabilities between your mail clients and your web Gmail.
If you’re trying to decide between using POP and using IMAP with Gmail, we recommend IMAP.
How much does IMAP cost? IMAP for Gmail is free.
Great! How do I get started?
First, you’ll need to enable IMAP in Gmail. Once IMAP is enabled, follow the configuration instructions for your client of choice. Currently, only the clients listed are supported for IMAP. If you’d like to download your Gmail messages with a different client, please check to see if it’s on our list of supported POP clients.
When you’ve enabled IMAP and set up your client, sign in to Gmail through the client and watch your messages arrive. You’ll notice that all of your custom Gmail labels will appear in your client as folders, with your labeled messages inside. While we’d like to make your IMAP experience match the Gmail web interface as much as possible, some Gmail-specific features and terms, such as conversation threading and stars, won’t appear in your client. Don’t worry; you can still perform all the usual Gmail functions, just in a slightly different way. The IMAP behavior chart shows you how to perform common functions on your IMAP client.
Please note that every client handles IMAP in a slightly different way. If you’re curious about the specific use of your client, contact the client’s support team.