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Contents [hide] 1 Proposal to Simplify Composite Collection Objects 1.1 Abbreviations and Terms 1.2 Existing Composite Collection Object 1.3 Simplified Collection Object 1.4 Questions / Issues

Proposal to Simplify Composite Collection Objects

Abbreviations and Terms

CAgg	Collection Aggregator
CMDP	Collection Metadata Provider
OAgent	Owner Agent for Collection
CR	Collection Record
M	Metadata about the collection that is not part of the composite object
M-MDP	Metadata Provider for Metadata (M)
Extra Parent	any parent collections besides NSDL Collection of Collections
CMgmt	NSDL Collection Management Metadata Provider
NSDL CR	NSDL Collection Records Metadata Provider
ncs:CMF	relationship ncs:collectionMetadataFor that identifies the real Collection Metadata Provider
EV	Metadata Provider | Aggregator)

Existing Composite Collection Object

Objects

Object	Usage Notes
CMDP	supposedly identifying MDP that provides metadata for resources in this NDR Collection
CAggr	handle representing the collection; has legacy ServiceDescription
CM	contains NDR collection metadata, eg. Title, Description, Contacts, ExternalID
CR	contains collection resource URL
OAgent	application agent, eg. NCS, -- VS. -- project agent, eg. Beyond Penguins
M	legacy metadata objects for collections that contain multiple metadata datastreams
M-MDP	provider for M, always one of NSDL Collection Management, NSDL Collection Record, or EV; has legacy ServiceDescription
parentCAggr

Relationships

Subject	Relationship	Predicate	Usage Notes
CMDP	metadataProviderFor	OAgent
CMDP	aggregatedBy	CAggr
CAggr	aggregatorFor	OAgent
CAggr	associatedWith	CR
CM	metadataProvidedBy	CMDP
CM	metadataFor	CAggr
CM	metadataFor	CR
M	metadataFor	CAggr	legacy outside the control of the composite object
M	metadataProvidedBy	M-MDP	legacy outside the control of the composite object
CAggr	memberOf	parentCAggr

Simplified Collection Object

Objects

Object	Usage Notes
CAggr	contains URL for collection resource, contains NDR collection metadata
OAgent	application agent, eg. NCS, -- VS. -- project agent, eg. Beyond Penguins
parentCAggr

Relationships

Subject	Relationship	Predicate	Usage Notes
CAggr	aggregatorFor	OAgent

Questions / Issues

• In NDR code, what limits metadata creation/modification in an NDR Collection?
  • Is it the CMDP aggregatedBy CAggr?
  • Or is it the OAgent that the CAggr is the aggregatorFor?
  • Or is it any agent with auth:authorizedToChange relationship with the Aggregator?

• When metadata is added to an NDR Collection, how does that metadata get attributed to a particular CMDP? The existing composite collection object was designed with the assumption of a one-to-one relationship between CAggr and CMDP, and thus it was assumed that all metadata in the CAggr would be attributed to the CMDP.

Ex. 

(P) -- CAggr - Beyond Penguins NSDL Library Collection
CMDP - Beyond Penguins
parentCAggr - NSDL Collection of Collections
OAgent - NCS
M - NCS Collection Record


(C1) -- CAggr - Beyond Penguins - OnRamp RSS Metadata Source
CMDP - Beyond Penguins
parentCAggr - (P) Beyond Penguinis NSDL Library Collection
OAgent - WFI
M - metadata about resources added through WFI


(C2) -- CAggr - Beyond Penguins - NCS Managed Metadata Source
CMDP - Beyond Penguins
parentCAggr - (P) Beyond Penguinis NSDL Library Collection
OAgent - NCS
M - metadata about resources added through NCS


When metadata is added to (P), it is assumed to be attributable to Beyond Penguins.
When metadata is added to (C1), it is assumed to be attributable to Beyond Penguins.
When metadata is added to (C2), it is assumed to be attributable to Beyond Penguins.

• If we drop the CMDP relationship, how is metadata provinence determined?

• If we drop CR, the resourceURL may never exist as a discoverable resource in the NDR.