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 # Introduction to Network Programming Homework
 
+## System Architecture
+
+- The client program uses a TUI framework 'bubbletea' in Go.
+- The auth server use HTTP with in-memory SQLite as backend.
+- After auth, you can select the role to connect using P2P.
+    - Server: listen for client to join
+    - Client: scan and choose server to join
+
+## Connections
+
+- The auth server uses HTTP RESTful API, with JSON format payload and HTTP
+Basic Auth.
+- The UDP part uses builtin 'net' package in Go, and use MessagePack with
+some pre-shared Magic Number to prevent spoofing.
+- The wordle server also uses HTTP RESTful API, with JSON format payload.
+
+## Gameplay
+
+- A Wordle replica with multiplayer support.
+- Players guess the 5-letter word within 6 round.
+- After each round the guess result of others will be shared between players.
+- The person who guess the word first wins.