Notes from Megameeting 24th November 2008


BruceAmbacher UM
HelenTibbo UNC
JohnGarrett GSFC
KatiaThomaz INPE, Brazil
MarkConrad NARA
RobertDowns CIESIN, Columbia University

Discussion took place of sections B5.2 and B5.3.


  • All to think about where Packaging Information and Descriptive Information should be treated.

BruceAmbacher >> (All): Where are we starting?
Mark Conrad >> (All): I think we were still working on B.5.2.
Mark Conrad >> (All): There are two comments on the supporting text one from me 
and one from Barbara.
Mark Conrad >> (All): Barbara is suggesting that we might want to list Dublin 
Core as a possible metadata set. I oppose this on two grounds. 1. I don't think 
such a suggestion should be in a mandatory section. 2. I would not recommend 
Dublin Core.
BruceAmbacher >> (All): Re: Mark's first comment - should we change the text of 
the supporting text to just show the source as producer or repository?
BruceAmbacher >> (All): I must be in a different document 
Mark Conrad >> (All): Bruce my comment had to do with whether or not we had two 
separate requirements here. One to capture the metadata. Another to document 
that they are doing so.
RobertDowns >> (All): Bruce, are you suggesting that we delete the words "or by 
producing it itself at ingest"
BruceAmbacher >> (All): I would simplify the statement to just show the source 
of the metadata as either created by producer or the repository.  I don't see 
the need for this heavy-handed statement and the "This is necessary..."
Mark Conrad >> (All): Bruce I am not sure I understand. Can you suggest what the 
revised text would look like?
BruceAmbacher >> (All): "The repository must show the source of its required 
metadata either from the producer or the repository." 
Helen Tibbo >> (All): I agree with Mark on this one - it would seem the support 
text is for a separate requirement. I actually think both requirements are 
BruceAmbacher >> (All): I can accept two statements.
Helen Tibbo >> (All): of course, the problem with showing how the metadata is 
secured is that there may be several different ways.
Mark Conrad >> (All): This requirement might be a good candidate for a 
hierarchical requirement.
BruceAmbacher >> (All): Do you have a proposal?
Mark Conrad >> (All): Not yet.
Mark Conrad >> (All): How about this? We deal with Barbara's comment, my other 
comment, and Katia's comment. Then I will come back with a proposed revised text 
for all of B.5.2.?
BruceAmbacher >> (All): OK
Mark Conrad >> (All): So Barbara's comment suggests recommending Dublin Core in 
the supporting text. I have outlined my objections to this. What do the rest of 
the group think?
Mark Conrad >> (All): Doh! Apologies. The Dublin Core comment was for B.5.1.!
JohnGarrett >> (All): OK, yes that's what I was seeing
Helen Tibbo >> (All): To my mind there is descriptive metadata (used for 
retrieval); administrative (rights etc,); preservation (provenance, etc); and 
technial (bits,bytes, etc. could be considered preservation).
BruceAmbacher >> (All): I don't support recommending any specific metadata 
standard at this time.  There are competing international standards and some 
repositories have pre-existing matadata standards their digital components must 
Mark Conrad >> (All): Helen, That is not how OAIS slices it.
Mark Conrad >> (All): Descriptive metadata and retrieval metadata are two 
separate sets under OAIS.
Helen Tibbo >> (All): Perhaps not but what would people use for retrieval if not 
descriptive content?
JohnGarrett >> (All): I wouldn't mind it in the discussion or maybe in examples, 
but I agree with Mark that DC doesn't belong in the normative sections.
Mark Conrad >> (All): We already addressed the Dublin Core comment last week. It 
was not included in the mandatory section of B.5.1. It was my mistake to start 
that conversation under B.5.2.
Mark Conrad >> (All): Helen, Take a look at the discussion of retrieval vs 
descriptive metadata under B.5.1.
KatiaThomaz >> (All): now I understand you...
JohnGarrett >> (All): In OAIS descriptive data is used primarily for retrieval.  
BruceAmbacher >> (All): John, Isn't it also used to understand the object and 
determine whether it is what you are looking for?  That is the traditional role 
of description.
JohnGarrett >> (All): From OAIS: "Descriptive Information:  The set of 
information, consisting primarily of Package Descriptions, which is provided to 
Data Management to support the finding, ordering, and retrieving of OAIS 
information holdings by Consumers."
Mark Conrad >> (All): Also from OAIS: "The Descriptive Information is that 
information which is used to discover which package has the Content Information 
of interest. Depending on the setting, this may be no more than a descriptive 
title of the Information Package that appears in some message, or it may be a 
fullset of attributes that are searchable in a catalog service."
JohnGarrett >> (All): I wouldn't really say that it supported understanding the 
object, but I would say that it helps you find what you're looking for.  So I 
think I agree with Bruce's intent.
KatiaThomaz >> (All): to really understand the object you have PDI
Mark Conrad >> (All): Take a look at page 4-35 of the OAIS. There is text and a 
diagram that shows the relationships of the various types of metadata to the 
JohnGarrett >> (All): Yes, I agree PDI is for real understanding of the object. 
Descriptive Information provides just enough understanding of what the object 
is to find and retrieve it.
BruceAmbacher >> (All): And PDI may say nothing about ordering or retrieving.  
That is associated with the dissemination role and may be variable depending on 
what the consumer wants.
KatiaThomaz >> (All): ok
Helen Tibbo >> (All): So I'm lost - are we saying descriptive metadata is used 
for finding and retrieval? 
KatiaThomaz >> (All): An Information Package is a conceptual container of two 
types of information called Content Information and Preservation Description 
Information (PDI). The Content Information and PDI are viewed as being 
encapsulated and identifiable by the Packaging Information. The resulting 
package is viewed as being discoverable by virtue of the Descriptive 
Mark Conrad >> (All): Helen, Yes.
Mark Conrad >> (All): See pages 4-34 of the OAIS for another useful diagram. 
"The Preservation Description Information requirements in an AIP are much more 
stringentthan the requirements for Preservation Description Information in the 
general InformationPackage. While no PDI objects are mandatory in an Information 
Package, all classes of PDIinformation must be present in an AIP. This is 
illustrated in figure 4-16. The contents ofeach type of PDI are left to the 
discretion of the individual archive."
JohnGarrett >> (All): Yes, I suggest that we use Descriptive Information 
(capitalized to make it clear that we are using the defined OAIS term) rather 
than saying descriptive metadata which could mean many things to different 
people.  Looking at wiki, I think we already agreed to that. 
Mark Conrad >> (All): John, Agreed.
KatiaThomaz >> (All): again from OAIS RM: The Descriptive Information is that 
information which is used to discover which package has the Content Information 
of interest. Depending on the setting, this may be no more than a descriptive 
title of the Information Package that appears in some message, or it may be a 
full set of attributes that are searchable in a catalog service.
Mark Conrad >> (All): Katia, Yes. The type of descriptive information that Helen 
was talking about would be found in the PDI.
KatiaThomaz >> (All): agreed with John
BruceAmbacher >> (All): We did change the Requirement to Descriptive 
Information.  Can we change supporting text likewise:  "The repository must show 
the source of its Descriptive Information."
JohnGarrett >> (All): Yes, I think we should.
Mark Conrad >> (All): Yes.
RobertDowns >> (All): Yes
KatiaThomaz >> (All): yes
Mark Conrad >> (All): So should we move to Katia's question about packaging 
BruceAmbacher >> (All): Mark, Does this modify your earlier view that this is, 
in essence, a separate requirement.  
KatiaThomaz >> (All): From OAIS RM: The Packaging Information is that 
information which, either actually or logically, binds, identifies and relates 
the Content Information and PDI. For example, if the Content Information and PDI 
are identified as being the content of specific files on a CD-ROM, then the 
Packaging Information would include the ISO 9660 volume/file structure on the 
CD-ROM, as well as the names and directory information of the files on CD-ROM 
KatiaThomaz >> (All): sorry
Mark Conrad >> (All): Bruce, It does not change my view that there are two 
requiremnts here. I will draft a hierarchical version of this requirement for 
the group to review once we settle the other issues for B.5.2.
JohnGarrett >> (All): If this requirement is about Descriptive Information 
(which we now say it is), then it does not include Packaging Information.  That 
may need a separate item.
BruceAmbacher >> (All): I would answer Katia's B5.2 question as NO, PDI does not 
contain packaging information since the DIP has variable content and hence the 
packaging will vary from order to order
KatiaThomaz >> (All): agreed
BruceAmbacher >> (All): On to B5.3?
KatiaThomaz >> (All): so, where will we deal with packaging information?
JohnGarrett >> (All): So this requirment will be that you need to have Descriptive 
Information.  I hearing that people think we also need a requirement 
that repository shows how it generates Descriptive Information.
Mark Conrad >> (All): Let's address John's question first. Do we need a separate 
Helen Tibbo >> (All): Wouldn't that be evidence of a sound process? If the 
process isn't sound then perhaps the DI wouldn't be either.
BruceAmbacher >> (All): We have been viewing this as an either/or - 
producer/repository.  Descriptive Information also could come from other 
Mark Conrad >> (All): Oh I thought you were asking a different question, John. I 
was thinking more like Katia's question. Do we need a separate requirement for 
packaging information.
KatiaThomaz >> (All): remembering that B1 deals with acquisition of content, B2 
with creation of the AIP, B3 with preservation planning, B4 with archival 
storage & preservation/maintenance of AIPs, B5 with information management and 
B6 access management
BruceAmbacher >> (All): Packing Information should be dealt with in 
Dissemination.  The actual content and sources will vary by the request
RobertDowns >> (All): On OAIS page 4-30, under Descriptive Information "The 
Descriptive Information is generally derived from theContent Information and 
BruceAmbacher >> (All): In B6 as Katia shows
JohnGarrett >> (All): I think that is a another question, but I was going back 
to what I thought was Mark's comment that we started with. 
KatiaThomaz >> (All): i think about b4 or b5, not b6
BruceAmbacher >> (All): Robert, I agree "generally" but there may be other 
sources sometimes
Mark Conrad >> (All): Bruce, no. Packaging information is a crucial part of 
binding the AIP to the PDI.
Mark Conrad >> (All): John. I will be proposing text to address my comment about 
two requirements for next Monday or more likely the following Monday.
BruceAmbacher >> (All): We are talking about two types of packaging information. 
 I agree with you regarding AIP-PDI.  I am only addressing the DIP process.
Mark Conrad >> (All): B.5. is about AIPs
BruceAmbacher >> (All): Agreed.
BruceAmbacher >> (All): texting causes delays in responding to threads and hence 
some confusion.
Mark Conrad >> (All): Katia, how would you propose we address packaging 
information in B.5.2.?
KatiaThomaz >> (All): from OAIS RM: Packaging Information: The information that 
is used to bind and identify the components of an Information Package. For 
example, it may be the ISO 9660 volume and directory information used on a CD-
ROM to provide the content of several files containing Content Information and 
Preservation Description Information.
KatiaThomaz >> (All): i think we should create another requirement
Helen Tibbo >> (All): OK, I have a head ache and I think it is mostly due to 
delays about and the multiple meaning of some of these terms (or the ways we are 
using them). We need to be VERY CLEAR in this section. If we can't follow what 
we are staying now, how can the poor repositories?
Helen Tibbo >> (All): Thus I would vote for separate requirements when we can, 
as that should simplify things for the repository.
Mark Conrad >> (All): Helen, This is what I have been saying about all of the 
RobertDowns >> (All): Perhaps Packaging Information should be addressed under B6 
Access Management.
Mark Conrad >> (All): Robert, We need to address packaging information for both 
AIPs (B.5.) and DIPs.
KatiaThomaz >> (All): packaging information comes before access
KatiaThomaz >> (All): and SIPs
Mark Conrad >> (All): Katia, Can you suggest the text of the new requirement for 
packaging information for next time?
JohnGarrett >> (All): I think my preference would be to talk about packaging 
information way back in B2.1 where we define the AIP.  There we talk about 
making clear what the links are between all the information objects.  I think 
that is Packaging Information.  We just didn't use the term there that I see.
BruceAmbacher >> (All): So B5.2 says we need Descriptive Information tied to the 
AIP.  A new requirement says the repository must identify the sources of that 
Descriptive Information. 
KatiaThomaz >> (All): what do you think about the better location?
KatiaThomaz >> (All): again: B1 deals with acquisition of content, B2 with 
creation of the AIP, B3 with preservation planning, B4 with archival storage & 
preservation/maintenance of AIPs, B5 with information management and B6 access 
Mark Conrad >> (All): I think that B.2. might be the appropriate place.
KatiaThomaz >> (All): so, a new requirement in B2...
JohnGarrett >> (All): Perhaps, but I think B2.1 might cover it with a slight 
BruceAmbacher >> (All): We are now on the brink of inserting Descriptive 
Information in B2; which I think is good.  I do not see the need (yet) for new 
requirements in B2, just refining.
JohnGarrett >> (All): I wasn't expecting to add Descriptive Information in B2, 
just Packaging Information.
KatiaThomaz >> (All): yes
Mark Conrad >> (All): Me too. Where does Descriptive Information come into the 
KatiaThomaz >> (All): why not packaging information and descriptive information 
in B5?
BruceAmbacher >> (All): Proposed B2.1: "Repository has Descriptive Information 
associated with each AIP or class of  AIP preserved by the repository that is 
adequate to fit long-term preservation needs. 
Mark Conrad >> (All): Bruce, no. That is clearly not the intent of B.2.1.
KatiaThomaz >> (All): i donīt like this...
RobertDowns >> (All): B2.1 discusses more than Descriptive Information.
KatiaThomaz >> (All): I vote to a new requirement
Mark Conrad >> (All): From the OAIS, page 4-35: "Each AIP is associated with a 
structured form of Descriptive Information called the Package Description, which 
enables the Consumer to locate information of potential interest, analyze that 
information, and order desired information. The information needed for one 
Access Aid is called an Associated Description. A single Package Description may 
contain several Associated Descriptions depending on the number of different 
Access Aids that can locate,visualize, retrieve or order the associated Content 
Information and PDI. Figure 4-17 is a UML diagram that models the Package 
Description and Access Aids."
KatiaThomaz >> (All): for packaging information
JohnGarrett >> (All): Yes I think B2.1 is about the definition of the AIP 
itself, not about DI which is separate information about how to find and 
retrieve the AIP.  I think Packaging Info should be discussed primarily in B2 
and Descriptive Info primarily in B5
KatiaThomaz >> (All): packaging information is a separate information too
JohnGarrett >> (All): Yes it is.
KatiaThomaz >> (All): look at the figure on page 2-5
Mark Conrad >> (All): Packaging Information and Package Description are two 
separate things. I think we may be confusing terms here.
JohnGarrett >> (All): But to define an AIP you almost need to talk about how it 
is packaged together.
KatiaThomaz >> (All): and a SIP and a DIP
JohnGarrett >> (All): Same goes for SIP or DIP, so packaging info may need to be 
discussed where SIP, AIP, and DIP are defined.
KatiaThomaz >> (All): or discuss this in B5 information management
BruceAmbacher >> (All): I have another engagement.  I will be with you next 
JohnGarrett >> (All): Yes, I think we may be confusing the two terms.
KatiaThomaz >> (All): yes, we must think more
Mark Conrad >> (All): So for next week. Everyone come prepared with their 
proposals of what should be mentioned where and we will proceed from there.
KatiaThomaz >> (All): ok.
Helen Tibbo >> (All): I think our home work should be to go back to OAIS, get 
the definitions of all these terms, check our glossary, and check how we are 
using what in the text here. I may or may not join next week as I will be on the 
road for one last trip in 2008.
Mark Conrad >> (All): Helen makes a good suggestion.

-- SimonLambert - 26 Nov 2008

Topic revision: r1 - 2008-11-26 - SimonLambert
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