3.5 KiB
Glossary
Action
Actor
Assertion
Attenuation
Capability
a.k.a. Cap
Pointer or handle denoting a live, stateful entity running within an actor. The entity accepts Preserves-format messages and/or assertions. The capability may be attenuated to restrict the messages and assertions that may be delivered to the denoted entity by way of this particular handle.
Compositional
Configuration Scripting Language
Conversational State
Dataspace
E
Embedded References
Entity
Event
Facet
Initial OID
Initial Ref
Macaroon
“Macaroons: Cookies with Contextual Caveats for Decentralized Authorization in the Cloud.”, by Arnar Birgisson, Joe Gibbs Politz, Úlfar Erlingsson, Ankur Taly, Michael Vrable, and Mark Lentczner. In Proc. Network and Distributed System Security Symposium (NDSS), 2014. [PDF]
Membrane
Message
Network
A network is a group of peers, plus a medium of communication, an addressing model, and an associated scope.
Object Capability Model
Observe
OID
Preserves
Record
a Preserves record
Reference
a.k.a. Ref
Relay
Relay Entity
S6
Schema
Scope
A scope maps refs to the entities they denote. Scopes exist in one-to-one relationship to networks. Because message bodies and asserted values contain embedded references, each message and assertion transmitted via some network is also inseparable from its scope.
Most actors will participate in a single scope. However, relay actors participate in two or more scopes, translating refs back and forth as messages and assertions traverse the relay.
Examples.
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A process is a scope for in-memory values: in-memory refs contain direct pointers to entities, which cannot be interpreted outside the context of the process's address space. The "network" associated with the process's scope is the intra-process graph of object references.
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A TCP/IP socket (or serial link, or WebSocket, or Unix socket, etc.) is a scope for values travelling between two connected processes: refs on the wire denote entities owned by one or the other of the two participants. The "network" for a socket's scope is exactly the two connected peers (NB. and is not the underlying TCP/IP network, HTTP network, or Unix kernel that supports the point-to-point link).
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An ethernet segment is a scope for values broadcast among stations: the embedded refs are (MAC address, OID) pairs. The network is the set of participating peers.
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A running web page is a scope for the JavaScript objects it contains: both local and remote entities are represented by JavaScript objects. The "network" is the JavaScript heap.
Supervision tree
Supervisor
Sync Peer Entity
Synchronization
(sync action)
Syndicated Actor Model
Often abbreviated SAM.
Source entities running within an actor publish assertions and send messages to target entities, possibly in other actors.
Essential idea: state replication is more useful than message-passing. (Message-passing protocols usually end up simulating it, badly, anyway.)