Which protocol is a TCP/IP mail delivery protocol?

Which protocol is a TCP/IP mail delivery protocol?

• A. Secure Shell (SSH)
• B. Session Initiation Protocol (SIP)
• C. Simple Mail Transfer Protocol (SMTP)
• D. Border Gateway Protocol (BGP)

Answer: (C)

Mail delivery over TCP/IP is handled by the Simple Mail Transfer Protocol. SMTP is designed to transfer messages from one mail server to another and from clients to servers, using TCP to ensure reliable delivery and a store-and-forward process across networks. In practice, SMTP is the standard backbone for sending emails across domains, while other protocols serve different roles: Secure Shell provides remote command access, SIP handles signaling for real-time communications, and BGP routes packets between networks rather than delivering mail. Retrieval of mail from a server is done with other protocols like POP3 or IMAP, not for delivering mail between servers.

Mail delivery over TCP/IP is handled by the Simple Mail Transfer Protocol. SMTP is designed to transfer messages from one mail server to another and from clients to servers, using TCP to ensure reliable delivery and a store-and-forward process across networks. In practice, SMTP is the standard backbone for sending emails across domains, while other protocols serve different roles: Secure Shell provides remote command access, SIP handles signaling for real-time communications, and BGP routes packets between networks rather than delivering mail. Retrieval of mail from a server is done with other protocols like POP3 or IMAP, not for delivering mail between servers.