Pop3 sent. IMAP beats POP in three areas
» Which is better to use, POP3 or IMAP » 08/27/2013
Which is better to use, POP3 or IMAP? To answer this question, let's first understand what it is and what it is intended for:
POP3 is a protocol for receiving email messages.
IMAP is a protocol that supports receiving, as well as the ability to manage mail that is located on the server.
If the POP3 protocol is selected in your client settings, then the following happens: the client program connects to the server, downloads new mail from yours and disconnects. In this case, the downloaded mail is deleted from the server. POP stands for Post Office Protocol, in other words, it works like a mailbox in your entrance - you pick up mail from it and it is nowhere else except your computer. You cannot see sent emails, only received ones. You cannot read this mail from another computer (smartphone\tablet\laptop) since it is no longer on the server. Pretty bad, you'll agree. The fact is that when this protocol was created, each user did not have several computers, and communication with the Internet was expensive and unstable. Therefore, it was important to quickly connect to the server, download all mail from your mailbox and terminate the connection. Nowadays, this protocol is used only when:
- The mailbox is used by only one person and only from 1 computer.
- Access to mail is required if there is no Internet connection.
- Mail server resources are limited and you cannot store much data on it.
In all other cases, it is better to use IMAP. It provides two-way communication between the server and the client. This means that after connecting to the server, the actions performed at the same moment are reflected on the server. IMAP became the first cloud protocol without even knowing it. With this protocol, unlike POP3, you access mail from various devices Anytime. You won't lose your messages, because they will always be on the server until you want to delete them. The main advantages of using IMAP are:
- support for flags (important, read, etc.);
- You can either store messages on the server or copy them to your computer;
- working with multiple mailboxes;
- simultaneous access with different devices;
- ability to search on the server.
Drawing a conclusion from the above, we can say that POP3 makes sense to use only if there is no possibility of a stable connection to the server, or the amount of memory on the server is very limited. In all other cases it is recommended using IMAP. And you should never forget about.
POP3
POP3 is a protocol for receiving email messages.
When viewing mail using the POP3 protocol, all emails are downloaded to the user's computer and automatically deleted from the server (although this can be disabled). All further actions with letters will be processed on the user’s computer.
The POP3 protocol is preferable if only one person from a single computer uses the mailbox, and access to mail is necessary even if there is no Internet connection.
IMAP
IMAP is a protocol that supports reception and management capabilities by email directly on the mail server.
When using the IMAP protocol, emails are always on the server and are downloaded from there every time they are viewed. This is very convenient when access to mailbox must have several people - all operations with letters that one of them performs (changing the status of a letter to “read”, moving letters between folders, etc.) will be seen by everyone else. The disadvantage is that to work with mail, even with old letters, you need an active Internet connection.
SMTP
An SMTP server is a mail server that only supports sending email.
When using an SMTP server, port 25 is used. Some ISPs block port 25. In this case, you will need to either contact your network administrator to unblock the port, or use the alternative port 587.
Chances are that most people reading this guide are already familiar with the most commonly used communication technology: email. But have you ever thought about how it actually works? In this article, we will learn how this service works and what POP3, SMTP and IMAP are.
POP3(protocol post office version 3) is often used to communicate with a remote email server and download messages to a local email client and then delete it on the server, for example, Thunderbird, Windows Mail, etc. However, email clients usually offer a choice whether or not to leave copies of messages on the server. If you use multiple devices to send messages, it is recommended to leave this feature enabled, otherwise, on another device you will not have access to sent messages that were not saved on the remote server. It is also worth noting that POP3 is a one-way only protocol, which means that the data is taken from remote server and are sent to the local client.
The default POP3 ports are:
Port 110 – port without encryption
Port 995 is an SSL/TLS port, also known as POP3S
Step 2 - Differences between POP3 and IMAP, and what are the ports for IMAP?
IMAP (protocol application level to access email), just like POP3 is used to receive email messages on a local client, however, it has a significant difference - only the headers are downloaded emails, the text of the letter itself remains on the server. This protocol Communication works in two directions; if changes occur on the local client, they are transmitted to the server. IN Lately IMAP has become more popular as email service giants like Gmail have started recommending it instead of POP3.
The default IMAP ports are:
- Port 143 – port without encryption
- Port 993 is an SSL/TLS port, also known as IMAPS
Step 3 - SMTP, the protocol for outgoing email communications
Simple Mail Transfer Protocol ( SMTP), is used to communicate with a remote server and then send messages from the local client to the remote server, and ultimately to the message recipient's server. On your email server, this process is controlled by a special service ( MTA). It's worth mentioning that SMTP is used solely for sending messages.
SMTP Ports:
- Port 25 – port without encryption
- Port 465 is an SSL/TLS port, also known as SMTPS
Conclusion
We hope that you now have a clear understanding of how email protocols work and what ports they use. In this tutorial, we learned what POP3, SMTP and IMAP are and what they are used for. For example, POP3 and IMAP are used for the same purposes, but they approach these tasks differently. IMAP leaves the content of the message on the server, and POP3 downloads it to your computer. Also, we found out what standard ports for SMTP, POP3 and IMAP.
This article covers the most commonly used Internet email protocols - POP3, IMAP, and SMTP. Each of them has a specific function and way of working. The content of the article explains which configuration is best suited for the user's specific needs when using an e-mail client. It also reveals the answer to the question of what protocol e-mail supports.
What is POP3?
Protocol Version 3 (POP3) is a standard email protocol used to receive email from a remote server to a local email client. Allows you to download messages to your local computer and read them even if the user is in offline mode. Please note that if you use POP3 to connect to your account messages are downloaded locally and deleted from the email server.
By default, the POP3 protocol runs on two ports:
port 110 is an unencrypted POP3 port;
Port 995 - This should be used if you want to connect to POP3 securely.
What is IMAP?
Internet Message Access Protocol (IMAP) is a protocol for receiving email messages, used to access email on a remote web server from a local client. IMAP and POP3 are the two most commonly used protocols for receiving emails and are supported by all modern email clients and web servers.
The POP3 protocol means that your email address is accessible only from one application, while IMAP allows simultaneous login from several clients at once. That's why IMAP fits better, if you plan to access your email from different places or if your messages are managed by multiple users.
The IMAP protocol runs on two ports:
port 143 is the default unencrypted IMAP port;
port 993 - this must be used if you want to connect securely using IMAP.
What is SMTP?
The protocol is standard protocol to send email over the Internet.
SMTP operates on three ports:
port 25 is unencrypted by default;
port 2525 - this is opened on all SiteGround servers if port 25 is filtered (for example by your ISP) and you want to send unencrypted emails using SMTP;
port 465 - This is used if you want to send messages securely using SMTP.
What protocols are used to exchange email? Concepts and terms
The term email server refers to the two servers required to send and receive emails, i.e. SMTP and POP.
The incoming mail server is the server associated with your email address account. It cannot have more than one incoming mail server. To access incoming messages, you need an email client—a program that can receive email from an account, allowing the user to read, forward, delete, and reply to messages. Depending on your server, you may be able to use a dedicated email client (such as Outlook Express) or a web browser. So, Internet Explorer used to access email-based accounts. Messages are stored on the incoming mail server until it is downloaded. Once you have downloaded your mail from the mail server, you cannot do it again. To successfully download data, you must enter correct settings in electronic mail program. Most incoming mail servers use one of the following protocols: IMAP, POP3, HTTP.
Outgoing mail server (SMTP)
This is a server used only for sending emails (to transfer them from your email client program to the receiver). Most outgoing mail servers use Protocol) to send correspondence. Depending on your network parameters The outgoing mail server may belong to your ISP or the server where you set up your account. Alternatively, you can use a subscription-based SMTP server that will allow you to send emails from any account. Due to spam issues, most outgoing email servers do not allow you to send emails unless you are logged into their network. A server with an open relay will allow you to use it to send emails, regardless of whether you belong to it network group or not.
Email Ports
For networks, a port means the end point of a logical connection. The port number determines its type. The following are the default email ports:
POP3 - port 110;
IMAP - port 143;
SMTP - port 25;
HTTP - port 80;
secure SMTP (SSMTP) - port 465;
secure IMAP (IMAP4-SSL) - port 585;
IMAP4 over SSL (IMAPS) - port 993;
Secure POP3 (SSL-POP) - port 995.
Email protocols: IMAP, POP3, SMTP and HTTP
Basically the protocol refers to standard method, used at each end of the communication channel. To deal with email, you must use a special client to access the mail server. In turn, they can exchange information with each other using completely different protocols.
IMAP protocol
IMAP (Internet Message Access Protocol) is a standard protocol for accessing email from your local server. IMAP is a client/server protocol in which email is received and data is stored by your Internet server. Since it only requires a small data transfer, it works well even with slow connection, for example, when connecting using a modem. When attempting to read a particular email message, the client downloads data from the server. You can also create and manage folders or mailboxes on the server, and delete messages.
POP3 protocol
Electronic transmission protocol POP mail(Post Office Protocol 3) provides a simple, standardized way for users to access mailboxes and download messages to their computers.
When using the POP protocol, all your email messages will be downloaded from the mail server to your local computer. You can also leave copies of your emails on the server. The advantage is that after downloading your messages, you can disconnect your Internet connection and read your email at your leisure without incurring additional communication costs. On the other hand, with this protocol you receive and download a lot unwanted messages(including spam or viruses).
SMTP protocol
The protocol is used by a mail transfer agent (MTA) to deliver electronic messages to a specific recipient server. SMTP can only be used to send emails, not to receive them. Depending on your network or ISP settings, you may only be able to use the SMTP protocol under certain conditions.
HTTP protocols
HTTP is not a protocol designed for email communication, but it can be used to access your mailbox. It is also often called web email. It can be used to compose or receive emails from your account. Hotmail - good example using HTTP as an email protocol.
Managed File Transfers and Network Solutions
Your ability to send and receive email is mainly due to three things: TCP protocols. They are SMTP, IMAP and POP3.
SMTP
Let's start with SMTP because its main function is different from the other two. SMTP, or Simple Mail Transfer Protocol, is primarily used to send email from mail client(For example, Microsoft Outlook, Thunderbird or Apple Mail) to your email server. It is also used to relay or forward mail messages from one mail server to another. This is necessary if the sender and recipient have different email service providers.
SMTP, which is specified in RFC 5321, uses port 25 by default. It can also use port 587 and port 465. The latter, which was introduced as the port of choice for secure SMTP (a.k.a. SMTPS), is considered deprecated. But in fact, it is still used by several email service providers.
POP3
Post Office Protocol, or POP, is used to retrieve email messages from Latest version The one that is widely used is version 3, hence the term "POP3".
POP version 3, specified in RFC 1939, supports extensions and several authentication mechanisms. Authentication features are required to prevent malicious users from accessing user communications.
The POP3 client receives email as follows:
connects to the mail server via port 143 (or 993 for SSL/TLS connections);
retrieves email messages;
serves to connect before closing the mail client application and download messages on demand.
connects to the mail server on port 110 (or 995 for SSL connections/TLS);
deletes copies of messages stored on the server;
disconnects from the server.
Although POP clients can be configured to allow the server to continue to store copies of downloaded messages, the steps described above are common practice.
IMAP
IMAP, especially Current version(IMAP4), is a more complex protocol. This allows users to group related messages and place them in folders, which in turn can be organized hierarchically. It is also equipped with message flags that indicate whether the message has been read, deleted, or received. It even allows users to search server mailboxes.
Operation logic (imap4 settings):
Please note that messages are not deleted on the server. This can have serious consequences. IMAP specifications can be found in RFC 3501.
Choosing between IMAP and POP3
Since the basic function of SMTP is fundamentally different, the choice dilemma better protocol usually only includes IMAP and POP3.
If server storage space is important to you, then choose POP3. A server with limited memory is one of the main factors that may force you to support POP3. Because IMAP leaves messages on the server, it can consume memory space faster than POP3.
If you want to access your mail at any time, then it is better to stick with IMAP. There is one good reason, which is why IMAP was designed to store messages on a server. It is used to search for messages from multiple devices - sometimes even simultaneously. So if you have an iPhone, Android tablet, laptop and desktop and you want to read email from any or all of these devices, then IMAP will be the best choice.
Synchronization is another advantage of IMAP. If you access email messages from multiple devices, you'll likely want them all to show any activity you've performed.
For example, if you read messages A, B, and C, you want them to also be marked as read on other devices. If you have deleted letters B and C, then you will want the same messages to be deleted from your inbox on all gadgets. All these synchronizations can only be achieved if you use IMAP.
Since IMAP allows users to organize messages hierarchically and place them in folders, it helps users better organize their correspondence.
Of course, everything functionality IMAPs come at a price. These solutions are more difficult to implement and the protocol ends up consuming a lot more CPU and RAM, especially when it performs the synchronization process. Actually high load CPU and memory drain can happen on both the client and server side if there are a ton of messages to sync. From this point of view, the POP3 protocol is less expensive, although less functional.
Privacy is also one of the issues that will greatly depend on the end users. They would generally prefer to download all email messages and not leave copies of them on an unknown server.
Speed is an advantage that varies and depends on the situation. POP3 has the ability to download everything mail messages when connected. And IMAP can, if necessary (for example, when there is insufficient traffic), download only message headers or certain parts and leave attachments on the server. Only when the user decides that the remaining parts are worth downloading will they become available to him. Therefore, IMAP can be considered faster.
However, if all messages on the server must be downloaded every time, then POP3 will be much faster.
As you can see, each of the described protocols has its own advantages and disadvantages. It's up to you to decide which features or capabilities are more important.
Also, the desired method of accessing the e-mail client determines the preferred protocol. Users who work from only one machine and use webmail to access their new emails, will appreciate POP3.
However, users who share mailboxes or access their emails with different computers, will prefer IMAP.
Spam firewalls with SMTP, IMAP and POP3
Most spam firewalls only deal with SMTP protocol and protect him. Servers send and receive email SMTP mail, and they will be checked by the spam firewall on the gateway. However, some spam firewalls provide the ability to protect POP3 and IMAP4 when external users need these services to access their email.
SMTP firewalls are transparent to end users; There are no configuration changes for clients. Users still receive and send email messages to the email server. Thus, Exchange or Dominos must configure routing of messages to the firewall based on a proxy server when sending email, and also provide the ability to send emails from the firewall.
Everyone knows how to work with email. Open the browser and search the right resource, log in and read the incoming email correspondence. The pop3 and imap mail protocols allow you to work with mail without a browser, through client programs, as if the files were located directly on the local computer.
POP3 is an application-level Internet protocol that provides access to the mail server via TCP/IP and using port 110.
IMAP is an application-level Internet protocol that provides access to the mail server via TCP and using port 143.
Difference between POP3 and IMAP
The difference between POP3 and IMAP is application-specific. Both protocols perform identical tasks, only POP3 allows you to download all files at once (correspondence is stored in these files), and IMAP first allows you to download a list of files and then selectively download them yourself. This is the main difference between the protocols, and the newer IMAP was created precisely to implement this difference: clients were not satisfied with the need to parse mail locally, while on the server the files were deleted after downloading. On IMAP servers, the user manages his messages independently.
pop3 clients connect to the network only to download files to the local computer, disconnect after the operation is completed, and further program operation takes place in offline mode. IMAP clients can work offline, but online provides more opportunities for them: for example, managing messages on the server. As a result, offline access requires fewer resources and is faster, while online access is more dependent on the network state and demonstrates relatively long time response.
POP3 assumes monouser access to a mailbox, IMAP allows multiple clients to connect to it, while the work of any of them is not limited, and everyone sees the changes made by others. IMAP also allows the user to see the status of messages, move them, create folders and delete them as if he were dealing with a local copy. Automatic removal There are no messages from the server.
Another important difference IMAP from POP3 - in the ability to expand the IMAP protocol and ultimately receive fine tuning, for example, client access rights to the server. Despite the fact that POP3, due to its longevity, is more widespread and easier to configure, IMAP seems more convenient when solving many problems, for example, corporate ones.
TheDifference.ru determined that the difference between IMAP and POP3 is as follows:
IMAP uses port 143, POP3 uses port 110.
IMAP works both online and offline, POP3 works only offline.
IMAP allows you to manage messages directly on the server, POP3 downloads files to the user's local computer.
POP3 provides faster access
In IMAP, you can configure the separation of access rights.