Simple Mail Transfer Protocol is a standard communication protocol for sending e-mail messages on business networks and the Internet. SMTP was developed in the early 1980s and remains one of the most popular protocols used worldwide. The reason for the popularity is also that at the given time there is no decent alternative technology.
SMTP is the TCP / IP protocol used when sending and receiving email. It usually operates with one of the other two protocols, POP3 or IMAP, which allows the user to save messages in the mailbox and periodically download them from the server. In other words, users usually use a program that uses SMTP to send and POP3 or IMAP to receive email.
Gmail's SMTP settings are required if you want to send an email from your Gmail account. The following is specific information. What do you need to configure SMTP for Gmail?
Network settings
Gmail SMTP default settings:
- server address: smtp.gmail.com;
- login: email address;
- password: your Gmail password;
- port (TLS): 587;
- port (SSL): 465;
- Gmail SMTP TLS / SSL required: yes.
It is important . In addition to these Gmail SMTP settings (ipb 3.4.6), you must allow the mail client to receive / download mail from the Gmail account.
POP3 and IMAP default settings
Download / receive mail through POP3 or IMAP servers. You can enable this type of access through Gmail settings on the Settings - Forwarding and POP / IMAP screen. Server settings for sending data via Gmail are required when using the mail client. You do not need to manually enter the settings when sending letters through a browser, for example, through Gmail.com.
Because Gmail is extremely popular, some email programs provide server data automatically when setting up your account.
Can't send mail through Gmail?
Some email applications use older, less secure technologies to log into your email account, and Google blocks these requests by default. If you cannot send mail with a Gmail account for this reason, it is unlikely that you are entering the wrong settings. In this case, you will receive a message related to the security of the mail client.
To solve this problem, log in to your Google account through a web browser and enable access through secure applications using the link.
Gmail settings SMTP server - how does it work?
All modern email client programs support SMTP. The options supported by the mail client include the IP address of the SMTP server (along with the addresses of the POP or IMAP server). Web clients embed the server address in their configuration, and PC clients provide SMTP settings that allow users to define their own server.
A physical SMTP server can only be designed to serve mail traffic, but it is often combined with POP3, and sometimes with other proxy server functions.
SMTP uses TCP port 25 for standard communications. To improve the protocol and help combat spam on the Internet, standard groups have developed TCP port 587 to support certain aspects of the protocol. Several web-based email services, such as Gmail, use the unofficial TCP port 465 for SMTP.
Teams
The SMTP standard defines a set of commands - the names of certain types of messages that send email clients to the server when requesting information.
The most important teams:
- HELO and EHLO - initiate a new protocol session between the client and server. EHLO requests responses to any additional SMTP extensions.
- MAIL - initiates sending a letter.
- RCPT - provides one address for the recipient of the current message.
- DATA - a command indicating the start of a message. Initiates a series of one or more subsequent messages, each of which contains a part of the message.
- RSET - when sending e-mail (after issuing the MAIL command) SMTP can reset the connection if it encounters an error in the protocol.
- NOOP - an empty message (“no operation”), designed as a kind of ping to check for responsiveness of the other end of the session.
- QUIT - termination of the protocol session.
The receiver of these commands answers with either successful or unsuccessful code numbers.
Problems
SMTP does not have built-in security features. Internet spammers actively used SNMP (network management protocol) at the initial stage of technology development, generating a huge amount of junk mail and delivering them through open SMTP servers. Spam protection has improved over time, but the security issue is still relevant. In addition, SMTP does not prevent spammers from setting up (via the MAIL command) fake email addresses.