The protocol which provides e-mail facility is:

Question

Accepted Answer

The correct option is (2):
The protocol that is fundamentally responsible for sending and routing electronic mail between mail servers is the **Simple Mail Transfer Protocol (SMTP)**. When an email client sends an email, it initiates a session with the mail server using SMTP to hand over the message. The sending mail server then uses SMTP again to communicate with the receiving mail server, which ultimately accepts the mail for the recipient. Therefore, SMTP is the essential application layer protocol that governs the transmission of email messages across a network, ensuring reliable and standardised delivery from the sender's system to the recipient's system.

The incorrect option is (1):
**FTP** stands for **File Transfer Protocol**, and its sole purpose is to transfer files (such as documents, images, and programs) between a client and a server on a computer network. It is designed specifically for two-way file transfers, facilitating operations like uploads and downloads. Although it is an application layer protocol, its function is entirely unrelated to the structured handling, formatting, and routing of email messages. Unlike SMTP, FTP does not have the commands or structure necessary to manage mail spools or message headers, making it incapable of providing the email facility.

The incorrect option is (3):
**TELNET** is a network protocol used to provide a bi-directional, interactive, text-oriented communication facility using a virtual terminal connection. Its main function is to allow a user to remotely log in to a different computer system on the network and execute commands as if they were physically present at the remote machine. It is essentially a remote access tool, not a dedicated mail transfer agent. While one could technically use TELNET to manually interact with a mail server by typing SMTP commands, TELNET is merely the mechanism for remote access, not the email protocol itself.

The incorrect option is (4):
The option "None of these" is incorrect because Option 2, **SMTP (Simple Mail Transfer Protocol)**, is the accurate and specific industry-standard protocol used for the transfer and routing of email messages. Since the protocol responsible for this core function is explicitly listed, the fourth option cannot be the correct answer.