The form of a waycast

    - A waycast is a directory enclosing waysource and ancillary components which together comprise
      a way declaration.
    ancillary components
        - The ancillary components include a certificate of authority.
    waysource
        - The waysource includes or surjoins one thoroughfractum, which models the caster’s way.



    ━━━━━━━━━━━
     Authority
    ───────────
        - The waycaster retains authority over the waycast in all its copies.
        - A copy of a waycast is authoritative iff:
            - Its certificate of authority is valid.
            - Its location is among the `authoritative_waycast_locations` of the certificate.
        certificate of authority
            / An ancillary component of the waycast.
            - The waycast includes a certificate of authority issued by the waycaster.
            - It is a file that contains:
                / The precise form here is yet to be detailed.
                waycaster_identifier
                    - The identifier of the waycaster.
                authoritative_waycast_locations
                    - The locations of the nominally authoritative copies of the waycast.
                    - Each location has the form of a URI.
                        : re `form of a URI` see https://tools.ietf.org/html/rfc3986#section-3
                timestamp
                    - A timestamp including a date.
            - A certificate is valid iff:
                - It is properly signed, viz. by a cryptographic private key
                  that matches its `waycaster_identifier`, itself a public key.
                    / The precise form of signature is yet to be detailed.
                - No other known certificate among waycast copies has all of:
                     - the same `waycaster_identifier`
                     - a proper signature
                     - an equal or later `timestamp`
                     - a difference in the rest of its content
        identifier of a waycaster
            - The identifier of a waycaster is a cryptographic public key.



                                                   \ Copyright © 2019, 2021  Michael Allan.  Licence MIT.