Which port is used for SMTP?

The Simple Mail Transfer Protocol (SMTP) uses port 25 for sending emails. This protocol is a key component of email communication, enabling the transfer of messages between email servers. SMTP is responsible for the routing and delivery of emails, and port 25 is specifically designated for this purpose in the Internet Protocol Suite.

Understanding the function of SMTP and its designated port is important for configuring email servers and troubleshooting email delivery issues. Other ports listed in the options serve different protocols: port 21 is used for FTP (File Transfer Protocol), port 53 is used for DNS (Domain Name System), and port 80 is utilized for HTTP (HyperText Transfer Protocol). Knowing these distinct port assignments helps in network management and security practices.