overall process

Note: this is off the top of my head, and has not been checked with the rest of the documentation.

Up to the time when a user tries an enquiry, the only messages that are needed are for answers to be recorded, locally.

When a user has sorted out an enquiry, and presses "try this enquiry...", the enquiry-core information is sent out in a find-fit-numbers message. It first goes to the communications hub, where the identity of the enquirer and the node is replaced by an opaque identifier. That is then sent out to all nodes.

Each node, on receiving this message, works out the number of fits and near fits. If the number of fits is clearly over 10, just a estimate number can be returned.

If the F < 10, F is returned. for near fits, the node keeps a track of which answers would be helpful from the node's own users.