What is the Full Form of SMTP in Computer Networks?
SMTP stands for Simple Mail Transfer Protocol, It is a concept related to Computer Networks. SMTP is used for email sending and receiving. It is sometimes paired with IMAP or POP3 (e.g., by a user-level application), which handles the retrieval of messages, whereas SMTP primarily forwards messages to a server.
SMTP is capable of sending and receiving email, but it is poor at queuing incoming messages, which is why it is frequently delegated to other protocols. When utilizing their own servers, proprietary systems such as Gmail have their own mail transfer protocols, but beyond that, they continue to rely on SMTP to send emails.
What are the Components of SMTP (Simple Mail Transfer Protocol)?
- Mail User Agent (MUA): It is the local user or client-end utility that enables the sending and receiving of email.
- Mail Submission Agent (MSA): The server that receives mail from the MUA and works with the MTA to deliver it.
- Mail Transfer Agent (MTA): It accepts incoming mail from local users and delivers it. Multiple MTP clients or servers can be involved in the transfer of email.
- Mail Delivery Agent (MDA): It delivers mail to the mailbox of a local recipient.
What are the types of SMTP?
There are two types of SMTP:
1. End to End: In this model, the client SMTP starts the communication whereas the SMTP at the receiver's end replies to the client's request. This model of SMTP helps to send emails to servers at various other institutions. This model acts as a mode of communication between two institutions.
2. Store and forward: This model unlike the end-end model sends emails within an organization. In this model, a client can send a message directly to the receiver because first the messages are stored on the company's server and then a copy of those messages is sent to the recipient's inbox.
How does SMTP work?
The working of SMTP is a 4 step process. It is based on the client-server model. The steps are as follows:
1. Submission of mails
The client after completing his email sends the completed mail to the SMTP server by using SMTP on TCP port 25.
2. Delivery of email
- Then the SMTP server divides the recipient mail address into two parts recipient user and domain name.
For eg studytonight@gmail.com where studytonight is the username of the recipients and gmail.com is the domain name.
- For instance, if a person is sending an email to himself or a person with the same domain name SMTP server will send the mail to the POP3 server, and from there it will reach the recipient.
- If the domain name of the recipient is different from the sender's email address, the MSA or the mail-sending agent sends the mail to the mail transfer agent (MTA), which searches the MX record from the domain name system to procure the recipient's domain name. The MX contains the record of a person's email address and IP address. Once the address is located MTA connects to the exchange server to transfer the mail.
3. Processing of mail
After the recipients receive the mail, the exchange server transfers the mail to the incoming server, which holds the mail till the time the recipient does not receive the mail.
4. Retrieval of mail
The mail is stored in the mail delivery agent (MDA) which can be accessed by login id and the password that is with the recipient. The mail is stored in the MDA till the time recipient does not retrieve it.
What are the advantages of SMTP?
SMTP has the following advantages -
- SMTP provides the simplest most convenient form of communication through email messages between two or more computers in a particular network.
- It is a very dependable communication tool in terms of outgoing messages.
- If somehow the message is not delivered the SMTP server will always try to resent the same email until the message is successfully delivered.
- SMTP also enables mass email marketing where a person can at once send emails to a broad range of users.
Conclusion:
SMTP (Simple Mail Transfer Protocol) is a crucial component of the email infrastructure that allows for the sending and receiving of emails across the internet. In this article, we explored the full form of SMTP and how it works in a simplified manner.
The above article covers everything you need to know about SMTP. The article covers everything such as what SMTP is and its full form, how it works, the components of SMTP, the types of SMTP, and the advantages of SMTP.
Frequently Asked Questions (FAQs)
1. What is the function of SMTP?
SMTP means Simple Mail Transfer Protocol is used to transfer emails and attachments to email clients through email servers.
2. How does SMTP work with TCP?
SMTP servers are always on-listening mode so whenever it detects any TCP connection from a client, the SMTP server proceeds the connection to port 25 to send an email.
3. What is the SMTP port number?
There are 4 SMTP port numbers 25, 465, 587, and 2525. SMTP transmission can use other ports too but they're not usually chosen for ISP (Internet Service Providers)
4. What is the basic operation of SMTP?
The basic operation of SMTP involves:
- Connection establishment
- Address resolution
- Message transfer
- Error handling
- Connection termination
5. Is SMTP based on TCP or UDP?
SMTP (Simple Mail Transfer Protocol) is based on TCP (Transmission Control Protocol). TCP is a reliable, connection-oriented protocol that guarantees the delivery of data in the order it is sent, making it suitable for applications like email that require reliable and accurate data transfer. SMTP uses TCP's features, such as connection establishment, error detection and correction, and flow control, to ensure the reliable delivery of email messages over the internet.
You may also like:
