FOAM incentivizes a distributed network of beacons with radio transceivers, called Zone Anchors, to be deployed. The first step in joining the network is sending signals to connect with and discover nearby Zone Anchors.
Proof of Location depends on accurate and synchronized clocks. Zone Anchors send messages until a consensus can be formed on the precise time. The timed difference of messages sent and received allow for location to be calculated and the geometry of the network to be determined. We rely on a Byzantine Fault tolerant clock synchronization protocol.
Once synchronized, groups of Zone Anchors can establish a Zone and pledge to offer location services that are enforced by smart contract safety deposits, which provide accountability to faulty behavior. A Zone maintains a quorum on Time and Space.
Zones can include time stamped messages from customers in a competitive market for a transaction fee. This is done while Zones are resynchronizing clocks and publishing their time logs to a data store. Validators provide fraud proofs and calculate Triangulations for precise location data to verify final Presence Claims.