Privacy, in plain words

Series of Tubes has no accounts, no email sign-ups and no cookies. Here is everything the game keeps on your device, everything that leaves it, and who keeps what.

On your device

Your saves, settings, badges and progress are kept in your browser's storage on this device. Nothing is uploaded unless you join a Multimode server (the game's multiplayer) or send a save somewhere yourself.

If you play Multimode, the browser also keeps:

• your network's private key, inside its save (it signs everything your network sends);
• what your servers sent about other networks, forgotten after 180 days without news of them;
• an operator key, only if you run a server and imported it (kept apart from every save).

Exports and shared saves never carry the private key. Only "Move to another device" makes a file with it: anyone with that file can speak as your network, so never share it or attach it to a bug report.

What goes to a Multimode server

Multimode is off until you join a server. Then your game sends signed records:

• your network's name, its AS number and its home market in the game;
• the game cities where it has POPs and exchange ports, its number of customers and its traffic numbers;
• its published peering policy, conditions and prices, and which networks it buys or sells transit from (never the price);
• deals with other players, sealed so that only the other player can read them: servers carry them without being able to see what was offered, at what price, or why someone said no;
• your real country, and only while "Share my country" is on. The server looks it up from your connection in a country-only database.

While you play, your game also sends its current numbers (the same as above, nothing more) every 10 seconds when they changed, so the leaderboards show what is happening now. Servers keep them only in memory, never on disk, and forget them 15 minutes after the last one.

Your network's name is public on every server you join, so better not to use your real name.

What servers keep, and for how long

• Traffic numbers: 72 hours (plus each network's newest ones).
• Your current numbers while you play: only in memory, 15 minutes after the last.
• Deal records: 30 days.
• A network's description: until it has been silent for 180 days.
• Operators' votes about a network: 97 days.
• Times are rounded to five minutes.

What servers never keep

IP addresses, any location finer than a country, or your device, browser, time zone, email or account. A server uses your connection's address only in memory, to look up the country and to slow down floods for a few minutes, and never writes it down or passes it on. Servers listed in the game promise that nothing in front of them logs addresses either. Server logs hold counts, error codes and network keys, never addresses.

Servers are run by players, not by us. The details are in the server documentation and the protocol.

The visit counter

On seriesoftub.es the game page loads a small visit counter (its script from jsDelivr, reporting to stats.seriesoftub.es). It sends:

• a page view: the page's address, the page you came from and the width of the window;
• how long the page stayed open;
• the names of some moments in the game, such as starting a new game, earning a badge or importing a save.

It sets no cookies and stores nothing in your browser. Copies of the game anywhere else send nothing, and this page loads no counter at all.

The counter is ridiculytics, made by the game's author and run on our own server. It has no database and writes nothing to disk: it only keeps running counts in memory, by page, by the site you came from (its host name only), by country, browser, operating system, device type and screen size class, and by the names of game moments. Your IP address is used only while your visit is being counted, to look up the country, and is never stored or logged. Unique visitors are counted with a one-way hash salted with a secret that changes every 24 hours and is never written down, so visits cannot be linked across days or across sites.

Leaving

• Leave a server in the Multimode sheet and your game stops talking to it. What it kept fades out within 180 days.
• Leave for good signs a goodbye that tells every server to delete your network's records at once (only the goodbye itself stays, 180 days, so it reaches every server), and the save forgets its Multimode identity.
• Deleting a save, or clearing the site's data in your browser, removes it from your device.