Mail server protocol

A mail server protocol is a set of rules and standards that govern the communication between a mail client (such as Microsoft Outlook or Mozilla Thunderbird) and a mail server (such as Microsoft Exchange or Postfix). The most common mail server protocols are:

1. SMTP (Simple Mail Transfer Protocol): used for sending emails between mail servers and between mail servers and mail clients.
   • Port: 25 (default), 587 (submission), 2525 (submission)
   • Authentication: username and password, or authentication tokens
2. POP3 (Post Office Protocol version 3): used for retrieving emails from a mail server to a mail client.
   • Port: 110 (default), 995 (SSL/TLS)
   • Authentication: username and password
3. IMAP (Internet Message Access Protocol): used for retrieving and managing emails on a mail server.
   • Port: 143 (default), 993 (SSL/TLS)
   • Authentication: username and password
4. EWS (Exchange Web Services): used for accessing Exchange Server mailboxes.
   • Port: 443 (SSL/TLS)
   • Authentication: username and password, or authentication tokens
5. MAPI (Messaging Application Programming Interface): used for accessing Exchange Server mailboxes.
   • Port: 135 (RPC), 443 (SSL/TLS)
   • Authentication: username and password, or authentication tokens

These protocols are used to perform various tasks, such as:

• Sending and receiving emails
• Retrieving email headers and bodies
• Deleting, moving, and copying emails
• Searching for emails using keywords and filters
• Managing email folders and labels

Mail server protocols are essential for email communication, as they enable mail clients and servers to communicate with each other and exchange email data.