Question

Why is connection establishment for mail transfer needed if TCP has already established a connection?

A. To ensure data integrity
B. To facilitate secure communication
C. To manage multiple email sessions
D. To establish a dedicated mail server

Answer 1

Answer is Option C. The establishment of a separate connection for mail transfer is necessary on the application level, even after having a TCP connection.

Step-by-step explanation:

The question refers to why a separate connection for mail transfer is needed in the context of email communication, even after a TCP connection has been established. The establishment of a connection specifically for mail transfer (typically done via protocols such as SMTP, POP3, or IMAP) is crucial not only for the initial TCP handshake that ensures packets will be sent and received correctly but for the application-level communication that follows. This application-level protocol is where not only the data transfer takes place but also where session management, authorization, and command exchange specific to email services occur.

Option C. To manage multiple email sessions is the most relevant answer. It addresses the application-level protocol's role in managing the transmission of emails which often involves multiple sessions, possibly simultaneous, and includes features not inherently part of the lower-level TCP protocol.