08 · The network: galaxies and mucuas

The baobab's fruit travels: by water, by animals, by people's hands. So does knowledge.

How knowledge travels

Each mucua keeps whole copies of the galaxies it takes part in. When two mucuas meet — over the internet, the local network, Tor, or a USB stick carried from one community to another — they sync: each one receives what the other has that's new. That's why the mucua works without internet: the archive is on it.

Texts (titles, descriptions, articles) always travel. Heavy files (videos, big photos) travel according to what each mucua wants to keep — a small mucua can have a video's description without the video, and request a copy when it needs it. Images inside articles and books, and the covers of roots, travel along with the text (up to 20 MB each).

Galaxies

☰ → Galaxies lists this mucua's galaxies.

• + new creates a galaxy on this mucua, or installs one that already exists on another mucua (by its address);
• Import .zip installs a galaxy from a file — the way to carry a whole galaxy on a USB stick, or to install a book like this one.

A galaxy's page shows its saberes, territories and mucuas.

Caring for a galaxy

People who sync or administer see the Care for button on the galaxy's page:

• ⟳ sync galaxy — talks to the connected mucuas now (sync also runs by itself, from time to time);
• read and write / read-only — locks writing on this mucua (useful on a mucua that only mirrors another community's galaxy); sync goes on;
• ⇩ Export .zip — the whole galaxy in one file, with its history and attachments, to install on another mucua in Galaxies → Import .zip. The zip also carries restricted saberes and the accounts: keep it safe;
• Who reads this galaxy — close the galaxy to some readers (chapter 07);
• Connected mucuas — who this galaxy syncs with; you can switch them on and off and connect new mucuas;
• Requests — the file copies that were requested and their path through the network;
• Routes — mucuas that form a circuit (the route of a USB stick, of a boat, of a visit) and pass requests on to each other, in order;
• History — every change recorded in the galaxy: who, when, in which saberes.

When a new galaxy is installed, the mucua already creates the links to the mucuas that came with it — but switched off: in Connected mucuas, turn on only the ones this mucua should talk to.

That is also where Heavy files in git lives: photos, audio and video live in the annex (which each mucua downloads when needed); git holds only the saberes' text. If something heavy landed in the wrong place (which happened, for instance, when git-annex was missing on the mucua), check shows what and move to the annex fixes it — the other mucuas get the change on the next sync.

Requesting a copy

On a saber's page, Copies shows which mucuas have the file. If it hasn't arrived here yet, request a copy creates a request: it walks through the network from mucua to mucua until it finds the file and brings it. To send a file from here to another mucua, choose deliver to… and the destination.

Whoever is short of space can drop the local copy of a file: the saber stays, only the downloaded file leaves this mucua (Baobáxia warns you if it's the only known copy).

Mucuas

☰ → Mucuas lists the network's mucuas. A mucua's page shows the galaxies and territories it takes part in, its saberes and, for whoever looks after it, the disk and memory.

Two ways of finding new mucuas:

• local network — mucuas announcing themselves on the same wi-fi show up by themselves; just authorise them (on both sides);
• discovery — got another mucua's address some other way (in a chat, on a card, a QR code, a USB stick)? Paste it there to see its galaxies and connect.

Without internet

• Two mucuas on the same local network sync directly, without internet.
• A galaxy zip on a USB stick carries a whole galaxy (Export .zip on one side, Import .zip on the other).
• Copy requests wait: when a path appears, they move on.

To talk about in the circle

• Which communities does yours want to exchange knowledge with? By which path (internet, local network, a visit, a USB stick)?
• How much space does the mucua have? Which heavy files does everyone need close by, and which can stay only on the mucua of whoever recorded them?