Privacy policy and external data transmission

Games with a friend (game server)

In games with a friend, your browser and the game server communicate over WebSocket. The information sent is the game type, the game settings (the rules for Gomoku and Checkers, and the number of players for Ludo and Chinese Checkers), the moves you make, draw offers in Checkers and their acceptance, resign and rematch actions, the action of starting with empty seats filled by the computer, the room ID, and the seat token (a random value that lets you return to your seat). The number you set in Hit and Blow and your piece setup in Gunjin Shogi are also sent to the server as moves. The server does not send these to your opponent until the game ends (in Gunjin Shogi, it sends only the positions of the pieces, not their types). Names and free-form text are not sent (there is no feature for entering them).

The contents of each room (such as the moves, settings, and seat tokens) are kept in the server’s memory. So that games can continue after the server restarts or stops abnormally, the contents are also written to a file on the server every 30 seconds when they have changed, and always when the server is stopped, and they are read back when the server starts. A room is deleted when 30 minutes have passed since all players disconnected, or when 24 hours have passed since it was created. A deleted room is also removed from the file at the next write (within 30 seconds).

IP addresses (for IPv6, the first 64 bits) are used in memory only to count the connections and the rooms created from the same internet connection against their limits, and are not written to logs or files. The records used for this counting are deleted within 1 hour after the connection ends. The server logs record the game type when a room is created, the numbers of connections and rooms, the types and counts of disconnections and errors, and error messages when processing fails because of a server bug (these may include moves or Hit and Blow numbers).

Game statistics

To fix bugs and improve the games, game statistics are sent to this site’s servers. The information sent is the game type, the mode (vs computer, pass and play on one device, solo, or with a friend), the computer’s level, the game settings, the result, the number of moves, the game length range, whether connections in games with a friend succeeded and the number of reconnections, 3D display failures and the rendering speed range, the types of loading failures, the device type (whether it is a phone, and memory and CPU core ranges), the browser and OS type, and an identifier that is created anew each time you open a page (it is not stored).

Room IDs, seat tokens, moves and board positions, Hit and Blow numbers, GPU model names, and page URLs are not sent. IP addresses are only used in memory to count the number of transmissions against a limit, and are not recorded. Records are deleted after 30 days.

Statistics are not sent when your browser’s Do Not Track (DNT) or Global Privacy Control (GPC) setting is on. You can stop them at any time with the switch at the bottom of the home page and each game page.

Access logs

Each time this site’s web server delivers a page or file, it records the IP address, date and time, URL, referrer, and browser type in its access logs. The logs are used to investigate failures and unauthorized access and to count visits. They are split by day, and records older than 10 days are deleted.