Definition of POP3-SMTP / IMAP

The email It is one of the oldest services that it offers us Internet, the result of the human need to communicate (either for work or outside of it), but the way of managing it has changed over time, following advances in technology.

At first, when using a computer was equivalent to managing a command line and the Internet had not yet reached homes in a massive way, the Users did not have to worry about configuring their emails, since everything resided on the server, and the administrator The system was in charge of configuring everything.

But times advanced, technologies evolved, computers reached homes, and so did the Internet. And, with the network of networks, the possibility of managing email from home, as well as having personal addresses as well as professional ones.

This is how they arise

the POP / SMTP and IMAP protocols, as ways in which a local email client can dialogue with the remote server.

In this way, we can be quietly at home, sleeping or away on the road, and our mail server (which will be running 24 hours a day, 365 days a year, and receiving mail) you will receive the messages sent to us, which we can retrieve by connecting from our

client local and downloading the mail.

The earliest versions of POP and IMAP date back to the mid-1980s,

although in the case of POP, the version with which it really managed to be used in a massive way, was the 3 of 1988, to the point that, nowadays, talking about POP and POP3 means exactly what same.

Both protocols differ slightly in the way they handle email, but how exactly?

POP / POP3 (Post Office Protocol) is intended only for receiving mail (not for sending it, for which it is accompanied by SMTP), downloading it completely

what allows its management offline, that is, disconnected from the network.

Not only are the elements of text that make up the email, but also the attached files such as images or programs that may have been attached at the source.

When downloading a message, it is deleted from the server, with the exception whether we keep a copy on it, an option that the vast majority of email clients allow us. This feature differentiates it from the system

IMAP (Internet Message Access Protocol), in which you need to be connected to the mail server to manage the messages

since only parts of messages are downloaded, such as the subject and a small part of the body, leaving the rest on the server. It also supports

folders on the server side, being able to sort the messages and retrieve them in order from any other client that we configure.

Both forms have advantages and disadvantages compared to the other; While POP / POP3 allows working in disconnection, the volume of messages occupies more space on our hard drives than if we work with IMAP.

This is something to keep in mind, since although many computers have large hard drives with hundreds or thousands of "gigabytes", the new formats of Ultralight convertibles (tablet + PC) integrate optical storage of a few gigabytes, so a very bulky mail will quickly consume space dedicated to Username.

IMAP is also a more complex protocol internally than POP / POP3, but that is something that is masked to the Internet user.

If before I said that the POP / POP3 serves exclusively for the reception of messages, this is accompanied by the

SMTP (Simple Mail Transfer Protocol), which works online and is capable of sending messages instantly.

It was defined in 1982, therefore prior to the previous ones, including the POP which it complements, but due to some deficiencies in the reception of messages, it is intended exclusively for sending. Its use can also be combined with IMAP, although it is not common.

Hosting service providers usually provide compatibility with both mail management systems,

both POP3 / SMTP and IMAP. To do this, they provide the user with configurations made up of incoming server, outgoing server, the respective ports used, your username and password (a couple of these different for each mailbox, although the servers and ports match), and some information on safety as, for example, if the sending of the username and password must be authenticated.

This configuration is repeated for each of the modes, POP3 / SMTP and IMAP.

This entire system of remote servers and local clients has been outdated for a long time for most Internet users who work as end users, who use the

webmail, consisting of accessing email messages, contacts and other functionalities through a browser thanks to a web interface.

Photos: Fotolia - Nikolai Titov - Dmitry

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