Federation API definition

[johnandersen777]

Have we thought about federation protocols / APIs? To enable registries to propagate uploaded content within a network of registries? Looking to come up to speed on any existing discussion if that's been touched on. Thank you!

• References
  • https://github.com/opencontainers/distribution-spec/blob/main/spec.md#endpoints
    • Looked here for relevant paths here but not seeing anything that looks like it's for notifications / inbox style eventing
  • https://github.com/sapcc/keppel
  • Use Case: Attestations of alignment to S2C2F and org overlays ietf-scitt/use-cases#14
    • Hoping we can align to similar federation protocols across transparency services and container registries so event stream consumers can work with the same protocol for each (ActivityStreams/Pub?)