Class BeaconAbstract

Implements 5. Beacons. Beacons are the mechanism by which a DID controller announces an update to their DID document by broadcasting an attestation to this update onto the public Bitcoin network. Beacons are identified by a Bitcoin address and emit Beacon Signals by broadcasting a valid Bitcoin transaction that spends from this Beacon address. These transactions include attestations to a set of didUpdatePayloads, either in the form of Content Identifiers (CIDs) or Sparse Merkle Tree (SMT) roots. Beacons are included as a service in DID documents, with the Service Endpoint identifying a Bitcoin address to watch for Beacon Signals. All Beacon Signals broadcast from this Beacon MUST be processed as part of resolution (see Read). The type of the Beacon service in the DID document defines how Beacon Signals SHOULD be processed. did:btc1 supports different Beacon Types, with each type defining a set of algorithms for:

1. How a Beacon can be established and added as a service to a DID document.
2. How attestations to DID updates are broadcast within Beacon Signals.
3. How a resolver processes a Beacon Signal, identifying, verifying, and applying the authorized mutations to a DID document for a specific DID. This is an extendable mechanism, such that in the future new Beacon Types could be added. It would be up to the resolver to determine if the Beacon Type is a mechanism they support and are willing to trust. If they are unable to support a Beacon Type and a DID they are resolving uses that type then the DID MUST be treated as invalid. The current, active Beacons of a DID document are specified in the document’s service property. By updating the DID document, a DID controller can change the set of Beacons they can use to broadcast updates to their DID document over time. Resolution of a DID MUST process signals from all Beacons identified in the latest DID document and apply them in order determined by the version specified by the didUpdatePayload. All resolvers of did:btc1 DIDs MUST support the core Beacon Types defined in this specification.

Beacon