ANCR current state: documentation of the receipt: Bob's notice, Alice's rights assertion, the notarized ANCR receipt
Next steps: Getting Determining ANCR receipt fields contributions to be part of the ISO 27560 WD. Publish anchor notice and consent receipt 1.2 spec, publish within via Kantara. Move from receipt definition to flows/protocol integrations.
The receipt creates transparency for Alice to discover and understand the sites/services terms, controller, etc. Steps 1-5 would be part of a Browser/extension implementation and could be broadcasted through headers (for example). Alice could include in her notarized receipt where BObBob's service could discover her information, eg her UMA Auth server or relevant resource locations.
From initial contactAfter discovery, Alice is able to monitor service term changes through the a registry. The 'registry' doesn't necessarily need to be a 3rd party, the site itself could host this to achieve the transparency outcomeoutcomes. Self assertion (public transparency) like this can still reference third parties, who don't need to know about ANCR. For example in the UK there is a public business registry with the Controllers listed, the site itself can reference that endpoint and provide that url in the receipt and further auto (public) discovery can transpire.
Can a service be registered with multiple registries? yes