Hi Deborah,


OAIS structures metadata around a single entity - the archived content
(Content Information). PREMIS structures metadata around four entities
(Objects, Agents, Rights, and Events). The PREMIS Object entity roughly
corresponds to OAIS's Content Information, but there are no equivalent
OAIS entities for Agents, Rights, or Events. So when we did the mapping
we decided to extend the information types defined in OAIS to each of
the PREMIS entities. So for example, Reference Information is used to
identify Content Information; by extension, Reference Information
identifies an Event. Provenance information records various aspects of
the Content Information's history; by extension Provenance information
records various aspects of an Event's history (e.g., when it occurred,
what its outcome was, etc.). As you point out, this approach does not
strictly adhere to the OAIS definitions, but we thought it worked pretty


Alternatively, you could retain the OAIS principle that all metadata is
structured around the Object; in this case, you might say, for example,
that all Agent-related metadata is part of an Object's Context
Information (if you accept the proposition that Agents are part an
archived object's context). There is some merit in this approach as


Anyway, this was the thinking that went into the mapping. However, it is
not set in stone, it was just a way to set the PREMIS metadata in an
OAIS context. Alternative approaches and mappings are welcome!






From: PREMIS Implementors Group Forum [mailto:[log in to unmask]] On Behalf Of
Deborah Woodyard-Robinson
Sent: Tuesday, August 22, 2006 11:51 PM
To: [log in to unmask]
Subject: [PIG] OAIS : PREMIS mapping question


Dear PIG-list


I've been looking at the OAIS/PREMIS mapping docs on the swiki and I'm
not sure I completely agree with the mapping of the entities other than
Object. Perhaps someone else can explain for me...


The easiest way for me to illustrate is with an example. The Excel
spreadsheet and diagrams in the PowerPoint presentations show a mapping
for the identifier semantic units for the agent, event and rights
entities to OAIS Reference Information. However in the OAIS it states
that Reference Information pertains to  "identifiers for the Content


The identifiers for the entities other than Object are not identifiers
for the Content Information, they are identifiers (pertaining to PREMIS
entities) to reference and structure the metadata about events, agents
and rights in the Context Information and Provenance information (and
perhaps Fixity Information depending on the event type).


Do you see my point or am I off on another planet missing the real




Deborah Woodyard-Robinson  
Woodyard-Robinson Holdings Limited
PO Box 31308, Ilam
New Zealand 
+64 (0)3 355 4486 (land line)
+64 (0)21 234 7064 (mobile)
Skype: debwoodyard-robinson