Which TCP port is commonly used for email submission by an authenticated email client?

Options

  • A. 25
  • B. 110
  • C. 587
  • D. More than one of the above
  • E. None of the above

Correct Answer (Detailed Explanation is Below)

C. 587

Detailed Explanation

Correct Answer: Port 587

  • Port 587 is commonly used for message submission by email clients.
  • It generally supports authentication and STARTTLS encryption.
  • Port 25 is primarily used for SMTP server-to-server transfer.