SMTP (Simple Mail Transfer Protocol) is primarily used for sending and relaying email messages between servers, facilitating the process of email delivery from the sender to the recipient's mail server. In contrast, POP (Post Office Protocol) is utilized by email clients to retrieve emails from the server, allowing users to download their messages for local access. While SMTP handles the outbound communication, POP focuses on the inbound retrieval of emails. Together, they enable the full cycle of email communication.
There are many more than three protocols which can operate at the application layer. Some of these are; Telnet FTP TFTP SMTP IMAP POP DNS RARP BOOTP SNMP CMOT
HTTP Belongs to the Application layer. Other transfer protocols like POP,FTP,SMTP etc also belongs to this layer
Simple Mail Transfer Protocols (SMTP) commands, control and manage the sending of emails by using a set of protocols which are instructions and rules that facilitate the emails transfer across networks.
SMTP and POP are two of the three methods for handling email. POP stands for Post Office Protocol and allows you to download email from a server, and SMTP which stands for Simple Mail Transfer Protocol, allows you to send email.
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tftp snmp nfs
SMTP - 25, 465, and 587 POP - 109, 110, and 995 IMAP - 143, 220, and 993
SMTP was designed to send email between computers in network. And uses TCP for reliability.
Gmail uses the technology or the protocols to send mails. It works on port number 487 for SSL. IMAP and SMTP are the protocols used.
SMTP (simple transfer mail protocol) which is used as the outgoing mail server and it uses port number :25 POP3 (Post Office Protocol 3) is the most recent version of a standard protocol for receiving e-mail. POP3 is a client/server protocol in which e-mail is received and held for you by your Internet server and it uses port 110
Ftp and smtp ( simple mail transfer protocol)
Both protocols are used to transfer files from one host to another. When transferring the files, both persistent HTTP and SMTP use persistent connections.