Explanation

Annex E Relationship to ActivityPub

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This page holds informative Annex E of the Vultron Protocol Specification: where the protocol follows ActivityPub conventions and where it adds constraints.

Annex E — Relationship to ActivityPub [I]

Vultron uses the ActivityStreams 2.0 vocabulary as its wire format. This version does not require full ActivityPub server behavior; the roadmap is at §1.3 Relationship to Existing Standards.

Where Vultron follows ActivityPub conventions:

Actors are identified by Uniform Resource Identifier (URI) and expose an inbox and an outbox.
Messages are Activities with type, actor, object and id.
Delivery is a Hypertext Transfer Protocol (HTTP) POST to the recipient's inbox.

Where Vultron adds constraints ActivityPub does not impose:

Case-scoped messages route through the participant holding the Case Manager role rather than directly between participants (§5.4.2 Routing Topology).
A case ledger entry's payload snapshot MUST be the asserted activity exactly as it was sent, references included (§5.5 Serialization), because the entry hash covers only what the snapshot carries.
The Vultron vocabulary extends the ActivityStreams vocabulary with the object types of §5.2 Object Types.