How to design a (SMTP, POP3) Mail server C++ Guided project

Explain the differences between iMap, Pop3, and SMTP, showing how iMap keeps mail on the server, Pop3 enables offline reading, and SMTP handles sending, with ports 143, 110, and 25.

Explore smtp mail transfer on port 25 between servers, and how pop3 and imap retrieve mail for clients—pop3 offline, imap sync—plus socket-based server design and c++ clients.

Learn pop version 3 commands and mail drop state transitions, from authorization to update, with examples of user, pass, list, retr, delete, noop, reset, top, last, and quit.

Design a generic, multi-threaded mail server in C++ with mutex protection, loading user data from the mails directory via LoadMailServer(), enumerating user folders and tracking last messages and lock state.

Learn to design a multi-threaded C++ mail server by binding IP and port, listening for client connections, accepting each connection, and spawning a thread per client on port 8080.

Create a Pop3 user class to store each logged-in user's emails (serial, file size, sender, date, and deleted flag) in a vector and integrate with the connection handler and process command.

Design a per-client POP3 connection handler that greets, receives commands in a loop, and uses a mutex to cap active threads at 20 with default responses.

Create a process command function to handle POP3 commands and authenticate users via text file. Manage authorization, transaction, and updating states with a function array that maps commands to handlers.

Explain how to implement the sendResponse function to send client messages using positive and negative responses, with skipWhitespaces to sanitize input in a C++ smtp pop3 mail server project.

Explore processing the user password or access token with the RPOP command, verify credentials against a username-password list, then validate the email before sending a positive response.

Explore how a pop3 server verifies the user command by checking the authorization code and email, then moves from authorization to transaction state and locks the user mail folder.

Use the course q&a to ask any questions about designing a smtp pop3 mail server in c++, and receive prompt, helpful answers from the instructor.

Use the log mail function to check and lock the mail drop, then getmail reads the mail folder and builds the emails vector with sender, date, size, and deleted status.

Use the stat and list commands to obtain mail drop statistics and per mail details, including total count, size, and each message index, sender, date, and size, with state checks.

Delete a mail in a C++ mail server using DELE, checking the transaction state and message id, and marking it deleted. Reset with RSET to unmark deletions and refresh mail.

Retrieve command returns full mail content via RETR after validating transaction state and message id, sending content with crlf line endings. Top limits lines when needed.

Develop a POP3 mail server in c++ that processes noop, top, and quit commands, extracting message id and line count for top, and deleting marked messages on quit.

Design and test a full mail server client in C++, focusing on a command-line interface and a grid GUI, with parallel sending and fetching via sockets and threads.

Design a Qt client mainwindow layout with a text browser and a send button. Connect a tcp socket to localhost:8080, handling ready read and disconnect via signals and slots.

Design and implement TCP signal-slot handling in a Qt C++ mail client: read data with readyRead, emit new messages, manage disconnects, and handle socket errors while sending UI messages.

Demonstrate end-to-end testing of a C++ POP3 client–server design by running the server on port 8083 and validating core commands with visible client messages.