Revision as of 14:37, 3 February 2008 by Paul.socialphysics.org
This page describes and defines a Higgins ContextId.
- A ContextId is a kind of Attribute that uniquely identifies the instance of a Context that contains it.
- The value of a ContextId MUST be a single instance of a ContextIdDatatype.
- Two different ContextIds may refer to the same Context.
- If the value of a ContextId is resolvable, its value should dereference the information necessary to discover how to access a Context. See Context Discovery.
- It is not required for a ContextIds to resolve to a Context instance in which case this is referred to as an abstract ContextId. However, most Contexts are not abstract, and can be resolved a network (or local) data access service to discover the information necessary to access the Context.
ContextIds and IdAS
- The Identity Attribute Service (IdAS) can be used as a service to access a Context given a ContextId.
- If two ContextId's values are equal, they refer to the same underlying Context, although not necessarily the same Context "container" instance returned by IdAS. This means that, as a requester of information, different clients of IdAS may see different subsets of the Context based on the authorization passed in during authentication.
- A given ContextId may be used against multiple Context Providers to produce the same Context (although, as mentioned, different Context instances).
- Context Discovery
- Context Discovery Components
- Higgins XRDS Service Endpoint
- Higgins XDI Context Reference