Digital Object Management

B1. Ingest: acquisition of content

Acquisition involves a crucial interaction between repository and depositor. Success in this phase of ingest indicates the repository’s ability to gain sufficient control over the content.

Repositories are likely to differ the most in this area of ingest processes, depending on the type of material they collect and their relationships with its producers. For any repository, it can be stated with some confidence that ingest finishes when an Archival Information Package (AIP) and its associated metadata are secure in the repository, including the creation of any security copies. It is more difficult to make a general statement about when ingest begins. Some repositories will have content submitted to them by producers, perhaps unexpectedly. Others will actively go out and seek content and request it from producers. Some producer-repository relationships will be more collaborative, making it less clearcut who initiates a particular transaction.

Relationships between producers and repositories that affect ingest can differ greatly in their formality and the extent to which obligations are placed on different parties. National archives, deposit (copyright) libraries, and institutional repositories may be able to compel their producers (government agencies and publishers) to provide content, but may have little or no control over its form. Other repositories may not be able to compel producers to offer content, but might be able to select the form of acceptable content, whether that applies to file formats or minimal metadata standards, for instance. Some repositories (Web archives, for example) may have little or no relationship with the producers of the content they preserve.

Given these differences, some of the requirements here are very general and require judgments about what is appropriate for a repository given its stated mission and the needs of its designated community(ies). But the result that all repositories are trying to achieve is the same: to preserve content that is understandable and usable in the long term. For more detailed information and thorough discussion of ingest and applicability, see Appendix 4: A Perspective on Ingest.

-- KatiaThomaz - 10 May 2007 - New item for “repository has developed criteria for the selection of its digital objects” (see NESTOR CCTDR 1.1). DonaldSawyer - This could be considered to be covered under B1.1 text, but B1.1 text could be expanded to make this clearer.

  • KatiaThomaz - I don´t know if my English comprehension is not good, but I think digital object properties don´t include criteria for the selection of digital objects. DonaldSawyer - I now think it may be good to call this out as a separate item for clarity.

B1.1 Repository identifies properties it will preserve for digital objects.

This process begins in general with the repository's mission statement and may be further specified in pre-accessioning agreements with producers or depositors (e.g., producer-archive agreements) and made very specific in deposit or transfer agreements for specific digital objects and their related documentation. For example, one repository may only commit to preserving the textual content of a document and not its exact appearance on a screen. Another may wish to preserve the exact appearance and layout of textual documents, while others may choose to normalize the data during the ingest process. If unique identifiers are associated with digital objects before ingest, they may also be significant properties that need to be preserved.

Evidence: Mission statement; submission agreements/deposit agreements/deeds of gift; workflow and policy documents, including written definition of properties as agreed in the deposit agreement/deed of gift; written processing procedures; documentation of properties to be preserved.

B1.2 Repository clearly specifies the information that needs to be associated with digital material at the time of its deposit (i.e., SIP).

For most types of digital objects to be ingested, the repository should have written criteria, prepared by the repository on its own or in conjunction with other parties, that specify exactly what digital object(s) are transferred, what documentation is associated with the object(s), and any restrictions on access, whether technical, regulatory, or donor-imposed.

The level of precision in these specifications will vary with the nature of the repository's collection policy and its relationship with creators. For instance, repositories engaged in Web harvesting, or those that rescue digital materials long after their creators have abandoned them, cannot impose conditions on the creators of material, since they are not "depositors" in the usual sense of the word. But Web harvesters can, for instance, decide which metadata elements from the HTTP transactions that captured a site are to be preserved along with the site's files, and this still constitutes "information associated with the digital material." They may also choose to record the information or decisions -whether taken by humans or by automated algorithms- that led to the site being captured.

Evidence: Transfer requirements; producer-archive agreements.

B1.3 Repository has mechanisms to authenticatevalidate the source of all materials.

The repository's written standard operating procedures and actual practices must ensure the digital objects are obtained from the expected source, that the appropriate provenance has been maintained prior to submission, and that the objects are the expected objects. Confirmation can use various means including, but not limited to, digital processing and data verification and validation, and through exchange of appropriate instrument of ownership (e.g., submission agreements/deposit agreement/deed of gift).

Evidence: Submission agreements/deposit agreements/deeds of gift; workflow documents; evidence of appropriate technological measures; logs from procedures and authentications.

B1.4 Repository’s ingest process verifies each submitted object (i.e., SIP) for completeness and correctness as specified in B1.2.

Information collected during the ingest process must be compared with information from some other source --the producer or the repository's own expectations--to verify the correctness of the data transfer and ingest process. The extent to which a repository can determine correctness will depend on what it knows about the SIP and what tools are available for verifying correctness. It can mean simply checking that file formats are what they claim to be (TIFF files are valid TIFF format, for instance), or can imply checking the content. This might involve human checking in some cases, such as confirming that the description of a picture matches the image.

Repositories should have established procedures for handling incomplete SIPs. These can range from rejecting the transfer, to suspending processing until the missing information is received, to simply reporting the errors. Similarly, the definition of "completeness" should be appropriate to a repository's activities. If an inventory of files was provided by a producer as part of pre-ingest negotiations, one would expect checks to be carried out against that inventory. But for some activities such as Web harvesting, "complete" may simply mean "whatever we could capture in the harvest session." Whatever checks are carried out must be consistent with the repository's own documented definition and understanding of completeness and correctness.

Evidence: Appropriate policy documents and system log files from system performing ingest procedure; formal or informal "acquisitions register" of files received during the transfer and ingest process; workflow, documentation of standard operating procedures, detailed procedures; definition of completeness and correctness, probably incorporated in policy documents.

B1.5 Repository obtains sufficient physical control over the digital objects to preserve them.

The repository must obtain complete control of the bits of the digital objects conveyed with each SIP. For example, some SIPs may only reference digital objects and in such cases the repository must get the referenced digital objects if they constitute part of the object that the repository has committed to conserve. This willIt is not always be the case that referenced digital objects are preserved: scholarly papers in a repository may contain references to other papers that are held in a different repository, or not held anywhere at all, and harvested Web sites may contain references to material in the same site or different sites that the repository has chosen not to capture or was unable to capture.

Evidence: Submission agreements/deposit agreements/deeds of gift; workflow documents; system log files from the system performing ingest procedures; logs of files captured during Web harvesting.

B1.6 Repository provides producer/depositor with appropriate responses at predefinedagreed points during the ingest processes.

Based on the initial processing plan and agreement between the repository and the producer/depositor, the repository must provide the producer/depositor , if it is appropriate to have such a plan, with progress reports at agreedspecific, predetermined points throughout the ingest process. Responses can include initial ingest receipts, or receipts that confirm that the AIP has been created and stored. Repository responses can range from nothing at all to predetermined, periodic reports of the ingest completeness and correctness, error reports and any final transfer of custody document. Producers/Depositors can request further information on an ad hoc basis when the previously agreed upon reports are insufficient.

Evidence: Submission agreements/deposit agreements/deeds of gift; workflow documentation; standard operating procedures; evidence of "reporting back."

-- KatiaThomaz - 10 May 2007 - I doubt about the need of this item. Is it necessary for long-term preservation? DonaldSawyer - Some submissions, such as scientific data, may continue for months or years. However text says it is not mandatory to to provide intermediate responses. As regards the need for long term preservation, I think this is addressing good practice in relation to the Producers and thus may be looked at as engendering trust. Is it absolutely needed to actually do the preservation task? Probably not, but this raises the issue of scope as to what the ISO standard should cover. I belive discussion is needed on this issue. KatiaThomaz - If we decide keeping this I think it should be moved to A5 Contracts, licences & liabilities

B1.7 Repository can demonstratehas written policies that indicate when it accepts preservation responsibilityformally accepted for the contents of theeach set of submitted data objects (i.e., SIPs).

A key component of a repository's responsibility to gain sufficient control of digital objects is the point when the repository manages the bitstream. For some repositories this will occur when it first receives the SIP transformation, for others it may not occur until the ingested SIP is transformed into an AIP. At this point, the repository formally accepts preservation responsibility of digital objects from the depositor.

Repositories that report back to their depositors generally will mark this acceptance with some form of notification to the depositor. (This may depend on repository responsibilities as designated in the depositor agreement.) A repository may mark the transfer by sending a formal document, often a final signed copy of the transfer agreement, back to the depositor signifying the completion of the transformation from SIP to AIP process. Other approaches are equally acceptable. Brief daily updates may be generated by a repository that only provides annual formal transfer reports.

Evidence: Submission agreements/deposit agreements/deeds of gift; confirmation receipt sent back to producer.

B1.8 Repository has contemporaneous records of actions and administration processes that are relevant to preservation (Ingest: content acquisition).

These records must be created on or about the time of the actions they refer to and are related to actions taken during the Ingest: content acquisition process. The records may be automated or may be written by individuals, depending on the nature of the actions described. Where community or international standards are used, such as PREMIS (2005), the repository must demonstrate that all relevant actions are carried through.

Evidence: Written documentation of decisions and/or action taken; preservation metadata logged, stored, and linked to pertinent digital objects, confirmation receipts sent back to providers.

-- MarkConrad - 05 Nov 2007 I would remove the reference to PREMIS. PREMIS often does not list what the "relevant action" should be.

B2. Ingest: creation of the archivable package

Digital repositories must take actions to preserve the ingested information, and the things they disseminate to end users must be strongly linked to the original objects that were deposited. To paraphrase the OAIS, these requirements are meant to ensure that information (digital objects and all appropriate metadata) received and verified from each producer is put into the archival form (AIP) and is stored in archival storage for long-term preservation. More specifically, the repository must actually complete the ingest process, creating some appropriate form—identifiable as archival storage—in which to store the information. This includes addressing the linkage of appropriate metadata to meet the levels of understanding expected, the association of unique identifiers to be able to reference the digital content, the mapping from the submitted content to the AIP storage forms, and auditable provenance information ensuring no loss or corruption of content in developing the AIPs.

B2.1 Repository has an identifiable, written definition for each AIP or class of information preserved by the repository.

An AIP contains these key components: the primary data object to be preserved, its supporting Representation Information (format and meaning of the format elements), and the various categories of Preservation Description Information (PDI) that also need to be associated with the primary data object: Fixity, Provenance, Context, and Reference. There should be a definition of how these categories of information are bound together and/or related in such a way that they can always be found and managed within the archive.

It is merely necessary that definitions exist for each AIP, or class of AIP if there are many instances of the same type. Repositories that store a wide variety of object types may need a specific definition for each AIP they hold, but it is expected that most repositories will establish class descriptions that apply to many AIPs. It must be possible to determine which definition applies to which AIP.

While this requirement is primarily concerned with issues of identifying and binding key components of the AIP, B2.2 places more stringent conditions on the content of the key components to ensure that they are fit for the intended purpose. Separating the two criteria is important, particularly if a repository does not satisfy one of them. It is important to know whether some or all AIPs are not defined, or that the definitions exist but are not adequate.

Evidence: Documentation identifying each class of AIP and describing how each is implemented within the repository. Implementations may, for example, involve some combination of files, databases, and/or documents.

-- KatiaThomaz - 10 May 2007 - It seems that B2.1 could be combined with B2.2. DonaldSawyer - The TRAC document addresses the reason for separating them. Perhaps a discussion of the reasoning and examples given, for the split, is in order.

B2.2 Repository has a definition of each AIP (or class) that is adequate to fit long-term preservation needs.

In many cases, if the definitions required by B2.1 exist, this requirement is also satisfied, but it may also be necessary for the definitions to say something about the semantics or intended use of the AIPs if this could affect long-term preservation decisions. For example, say two repositories both only preserve digital still images, both using multi-image TIFF files as their preservation format. Repository 1 consists entirely of real-world photographic images intended for viewing by people and has a single definition covering all of its AIPs. (The definition may refer to a local or external definition of the TIFF format.) Repository 2 contains some images, such as medical x-rays, that are intended for computer analysis rather than viewing by the human eye, and other images that are like those in Repository 1. Repository 2 should perhaps define two classes of AIPs, even though it only uses one storage format for both. A future preservation action may depend on the intended use of the image—an action that changes the bit-depth of the image in a way that is not perceivable to the human eye may be satisfactory for real-world photographs but not for medical images, for example.

Evidence: Documentation that relates the AIP component’s contents to the related preservation needs of the repository, with enough detail for the repository's providers and consumers to be confident that the significant properties of AIPs will be preserved.

B2.3 Repository has a description of how AIPs are constructed from SIPs.

The repository must be able to show how the preserved object is constructed from the object initially submitted for preservation. In some cases, the AIP and SIP will be almost identical apart from packaging and location, and the repository need only state this. More commonly, complex transformations (e.g., data normalization) may be applied to objects during the ingest process, and a precise description of these actions (i.e., preservation metadata) may be necessary to ensure that the preserved object represents the information in the submitted object. The AIP construction description should include documentation that gives the provenance of the ingest process for each SIP to AIP transformation, typically consisting of an overview of general processing being applied to all such transformations, augmented with description of different classes of such processing and, when applicable, with special transformations that were needed.

Some repositories may need to produce these complex descriptions case by case, in which case diaries or logs of actions taken to produce each AIP will be needed. In these cases, documentation needs to be mapped between to individual AIPs, and the mapping needs to be available for examination. Other repositories that can run a more production-line approach may have a description for how each class of incoming object is transformed to produce the AIP. It must be clear which definition applies to which AIP. If, to take a simple example, two separate processes each produce a TIFF file, it must be clear which process was applied to produce a particular TIFF file.

Evidence: Process description documents; documentation of SIP relationship to AIP; clear documentation of how AIPs are derived from SIPs; documentation of standard/process against which normalization occurs; documentation of normalization outcome and how outcome is different from SIP.

B2.4 Repository can demonstrate that all submitted objects (i.e., SIPs) are either accepted as whole or part of an eventual archival object (i.e., AIP), or otherwise disposed of in a recorded fashion.

The timescale of this process will vary between repositories from seconds to many months, but SIPs must not remain in a limbo-like state forever. The accessioning procedures and the internal processing and audit logs should maintain records of all internal transformations of SIPs to demonstrate that they either become AIPs (or part of AIPs) or are disposed of. Appropriate descriptive information should also document the provenance of all digital objects.

Evidence: System processing files; disposal records; donor or depositor agreements/deeds of gift; provenance tracking system; system log files

B2.5 Repository has and uses a naming convention that generates visible, persistent, unique identifiers for all archived objects (i.e., AIPs ).

A repository needs to ensure that an accepted, standard naming convention is in place that identifies its materials uniquely and persistently for use both in and outside the repository. The “visibility” requirement here means “visible” to repository managers and auditors. It does not imply that these unique identifiers need to be visible to end users or that they serve as the primary means of access to digital objects.

Equally important is a system of reliable linking/resolution services in order to find the uniquely named object, no matter its physical location. This is so that actions relating to AIPs can be traced over time, over system changes, and over storage changes. Ideally, the unique ID lives as long as the AIP; if it does not, there must be traceability. The ID system must be seen to fit the repository’s current and foreseeable future requirements for things like numbers of objects. It must be possible to demonstrate that the identifiers are unique. Note that B2.1 requires that the components of an AIP be suitably bound and identified for long-term management, but places no restrictions on how AIPs are identified with files. Thus, in the general case, an AIP may be distributed over many files, or a single file may contain more than one AIP. Therefore identifiers and filenames may not necessarily correspond to each other.

Documentation must show how the persistent identifiers of the AIP and its components are assigned and maintained so as to be unique within the context of the repository. The documentation must also describe any processes used for changes to such identifiers. It must be possible to obtain a complete list of all such identifiers and do spot checks for duplications.

Evidence: Documentation describing naming convention and physical evidence of its application (e.g., logs)

DavidGiaretta: Should SIP's be assigned unique identifiers?

B2.6 (NOTE: THIS ITEM IS TO BE REMOVED BECAUSE IT HAS BEEN FOLDED INTO B1.1 AS AN EXAMPLE) If unique identifiers are associated with SIPs components before ingest, the repository preserves the identifiers in a way that maintains a persistent association with the resultant archived object (e.g., AIP).

SIPs will not always contain unique identifiers when the repository receives them. But where they do, and particularly where those identifiers were widely known before the objects were ingested, it is important that they are either retained as is, or that some mechanism allows the original identifier to be transformed into one used by the repository.

For example, consider an archival repository whose SIPs consist of file collections from electronic document management systems (EDMS). Each incoming SIP will contain a unique identifier for each file within the EDMS, which may just be the pathname to the file. The repository cannot use these as they stand, since two different collections may contain files with the same pathname. The repository may generate unique identifiers by qualifying the original identifier in some way (e.g., prefixing the pathname with a unique ID assigned to the SIP of which it was a part). Or it may simply generate new unique numeric identifiers for every file in each SIP. If it qualifies the original identifier, it must explain the scheme it uses. If it generates entirely new identifiers, it will probably need to maintain a mapping between original IDs and generated IDs, perhaps using object-level metadata.

Documentation must show the policy on handling the unique identification of SIP components as the objects to be preserved are ingested, preserved, and disseminated. Where special handling is Trustworthy Repositories Audit & Certification: Criteria and Checklist required, this must be documented for each SIP as a part of the provenance information capture (see B2.3).

Evidence: Workflow documents and evidence of traceability (e.g., SIP identifier embedded in AIP, mapping table of SIP IDs to AIPs)

-- KatiaThomaz - 10 May 2007 - I don’t see the need of putting the item in conditional once all SIPs have a unique identifier no matter if before, during or after the ingest process.

BarbaraSierman -This item is important when a producer sends a newer version of the object, the original unique identifier will help to refer to the right object. The same in case of delivery from the repository to the original deliverer.

DonaldSawyer - The text argues that not all SIP components (title should be clearer that this is addressing SIP components not identifiers of the SIPs themselves) will have unique identifiers. I believe this is true because SIP components may be simply put into generic containers within the SIP. However where the SIP components do have unique IDs, especially IDs that are widely recognized or are expected to be recognized by Repository users, the IDs need to be maintained and associated with relevant material in the AIP. Also, as Barbara points out, replacements may be facilitated by their retention. Therefore I believe the 'IF' is appropriate, and their retention is required.

DonaldSawyer - Upon further reflection, I recommend this be folded into requirement B 1.1 as an example because such identifiers would be significant properties that need to be preserved.

B2.7 Repository demonstrates that it has access to necessary tools and resources to establish authoritative semantic or technical context of the digital objects it contains. These tools and resources can be held internally or can be shared via, for example, a trusted set of registries.(i.e., access to appropriate international Representation Information and format registries).

The Global Digital Format Registry (GDFR), the UK National Archives’ file format registry PRONOM, and the UK Digital Curation Centre’s Registry Repository of Representation Information Registry(RRORI) are three emerging examples of potential international standardsexternal registries a repository might adopt. Whenever possible, tThe repository shouldmay use these types of standardized, authoritative information sources to identify and/or verify the Representation Information components of Content Information and PDI. This will reduce the long-term maintenance costs to the repository and improve quality control.

Any such registry is a specialised type of repository, which itself must be certified/trusted.

Most repositories will maintain format information locally to maintain their independent ability to verify formats or other technical or semantic details associated with each archival object. In these cases, the use of international format registries is not meant to replace local format registries but instead serve as a resource to verify or obtain independent, authoritative information about any and all file formats.

Good practice suggests that any locally held Representation Information should also be made available to other repositories via a trusted registry. In addition any item of Representation Information should itself have adequate Representation Information to ensure that the Designated Community can understand and use the data object being preserved

Evidence: Subscription or access to such registries; association of unique identifiers to format registries with digital objects; Viewable records in local format registry (with persistent links to digital objects); local metadata registry(ies); database records that include Representation Information and a persistent link to relevant digital objects.

MarkConrad - 25 May 2007 Can the GFDR, Pronom, and RepReg truly be called standards? aren't they repositories?

  • KatiaThomaz - I agree with Mark. They are repositories.
    • DavidGiaretta - not standards, I agree, but probably Registries of some sort. The important point is that whatever they are they must themselves be trusted to hold their digital information (in this case Representation Information) over the long term i.e. they must be trusted repositories.

  • DavidGiaretta - I think that Representation Information (which is much more than format ) can be very large and the amount one needs does change. That is the reason to allow Repositories to refer to something outside themselves yet still be certifiable. Clearly we cannot force the use of such registries. The aim is just to make their use acceptable.

MarkConrad - 25 May 2007 Should this item reference ISO/IEC 11179, Information Technology -- Metadata Registries (MDR)?

  • KatiaThomaz - Good point. I think it should.
  • DavidGiaretta - yes, that is one type of system, but we should allow for others.
  • DonaldSawyer - I would not include 11179. It has many components, and is a standard, which the others are not. I think the point was to give examples of registries and this doesn't fit that model.

*B2.8 Repository records/registers Representation Information (including formats) ingested.*

When international standards for the associated Representation Information are not available, the repository needs to capture such information and register it so that it is readily findable and reusable. Some of it may be incorporated into software. The Representation Information is critical to the ability to turn bits into usable information and must be permanently associated with the Content Information.

Evidence: Viewable records in local format registry (with persistent links to digital objects); local metadata registry(ies); database records that include Representation Information and a persistent link to relevant digital objects.

B2.9 Repository acquires preservation metadata (i.e., PDI) for its associated Content Information. Proposed Revision: Repository has documented processes for acquiring preservation metadata (i.e., PDI) for its associated Content Information and acquires preservation metadata in accordance with the documented processes.

Preservation metadata (PDI) is needed not only by the repository to help ensure the Content Information is not corrupted (Fixity) and is findable (Reference Information), but to help ensure the Content Information is adequately understandable by providing a historical perspective (Provenance Information) and by providing relationships to other information (Context Information). The extent of such information needs is best addressed by members of the designated community(ies). The PDI must be permanently associated with Content Information.

Evidence: Viewable records in local format registry (with persistent links to digital objects); local metadata registry(ies); database records that include Representation Information and a persistent link to relevant digital objects. Proposed Revision: Viewable documentation on how the repository acquires and manages Preservation Description Information (PDI) for reference, provenance, fixity, and context and viewable PDI records that have been acquired and managed for the Content Information in accordance with the documentation.

DonaldSawyer: PDI is a required set of information to ensure adequate Content Information preservation. As such the above text appears to be inadequate. While I believe the extent of such information needs to be agreed between the Designated Communities AND the Repository, it seems that for audit purposes there should be a resulting documented policy within the Repository on how these various PDI information categories are obtained, their extent, and how they are managed. Then, the respositories holdings of such information can be compared against the documented policy. The evidence text above appears to be focused on Representation Information which is NOT a componenet of PDI, but rather is a part of Content Information and is addressed in other requirements. If there is general agreement on the above, then an effort to rewrite this requirement can be started.

BarbaraSierman: I wonder if there are not situations where an agreement about the PDI with the Designated Community is rather difficult, not to say hardly possible. Take for example the National Libraries, they have a broad idea about the Designated Community!

B2.10 Repository has a documented process for testing understandability of the information content and bringing the information content up to the agreed level of understandability.

If Content Information or Preservation Description Information (PDI) is not directly usable by the current application tools of the designated community(ies), the repository needs to have a defined process for giving it usable form or for making additional Representation Information available (see B3.2).

Repositories that share the burden of ensuring that adequate metadata or documentation is captured or generated to meet a required degree of understandability can implement any number of procedures to address this requirement. Such repositories typically have a narrowly defined designated community, such as a particular science discipline.

Evidence: Retention of individuals with the discipline expertise; periodic assembly of designated or outside community members to evaluate and identify additional required metadata.

B2.11 Repository verifies each AIP for completeness and correctness at the point it is generated.

The AIP can be verified by comparision to its definition (see B2.2).

An AIP may be constructed from the parts or the whole of one or more SIPs.

If the repository has a standard process to verify SIPs for either or both completeness and correctness and a demonstrably correct process for transforming SIPs into AIPs (see B2.3), then it simply needs to demonstrate that the initial checks were carried out successfully and that the transformation process was carried out without indicating errors. On the other hand Repositories that must create unique processes for many of their AIPs will also need to generate unique methods for validating the completeness and correctness of AIPs. This may include performing tests of some sort on the content of the AIP that can be compared with tests on the SIP. Such tests might be simple (counting the number of records in a file, or performing some simple statistical measure such as calculating the brightness histogram of an original and preserved image), but they might be complex or contain some subjective elements.

Documentation should describe how completeness and correctness of SIPs and AIPs are ensured, starting with ensuring receipt from the producer and continuing through AIP creation and supporting long-term preservation. Example approaches include the use of checksums, testing that checksums are still correct at various points during ingest and preservation, logs that such checks have been made, and any special tests that may be required for a particular SIP/AIP instance or class.

Evidence: Description of the procedure that verifies completeness and correctness of the AIPs; logs of the procedure.

-- KatiaThomaz - 10 May 2007 - I doubt about the need of this item; (see B1.4).

  • DavidGiaretta - but B1.4 refers to SIP only whereas this refers to AIPs.
    • KatiaThomaz - but how could an AIP be uncomplete or uncorrect if its related SIPs were complete and correct?
  • BarbaraSierman - and how could you proce that it is complete and correct?
-- KatiaThomaz - 03 Sep 2007 - I propose something like this: B2.11 Repository generates complete and correct AIPs - Repository can demonstrate each AIP conforms to its definition (see B2.2) and is compatible to its related SIPs (see B2.3). This may include performing tests of some sort on the content of the AIP that be compared with tests on the SIP. Such testes might be simple (counting the number of records in a file, or performing some statistical measure such as calculating the brightness histogram of an original and preserved image), but they might be complex or contain some subjective elements.

[Note: Here in Brazil, in the first case we say you "criticize" the data, and in the second case we say you "consist" the data.]

B2.12 Repository provides an independent mechanism for audit of the integrity of the repository collection/content.

In general, it is likely that a repository that meets all the previous criteria will satisfy this one without needing to demonstrate anything more. As a separate requirement, it demonstrates the importance of being able to audit the integrity of the collection as a whole.

For example, if a repository claims to have all e-mail sent or received by The Yoyodyne Corporation between 1985 and 2005, it has been required to show that:

  • The content it holds came from Yoyodyne’s e-mail servers.
  • It is all correctly transformed into a preservation format.
  • Each monthly SIP of e-mail has been correctly preserved, including original unique identifiers such as Message-IDs.

However it may still have no way of showing whether this really represents all of Yoyodyne’s email. For example, if there is a three-day period with no messages in the repository, is this because Yoyodyne was shut down for those three days, or was the e-mail lost before the SIP was constructed? This case could be resolved by the repository amending its description of the collection, but other cases may not be so straightforward.

A familiar mechanism from the world of traditional materials in libraries and archives is an accessions or acquisitions register that is independent of other catalog metadata. A repository should be able to show, for each item in its accessions register, which AIP(s) contain content from that item. Alternatively, it may need to show that there is no AIP for an item, either because ingest is still in progress, or because the item was rejected for some reason. Conversely, any AIP should be able to be related to an entry in the acquisitions register.

Evidence: Documentation provided for B2.1 through B2.6; documented agreements negotiated between the producer and the repository (see B 1.1-B1.9); logs of material received and associated action (receipt, action, etc.) dates; logs of periodic checks.

B2.13 Repository has contemporaneous records of actions and administration processes that are relevant to preservation (AIP creation).

These records must be created on or about the time of the actions they refer to and are related to actions associated with AIP creation. The records may be automated or may be written by individuals, depending on the nature of the actions described. Where community or international standards are used, such as PREMIS (2005), the repository must demonstrate that all relevant actions are carried through.

Evidence: Written documentation of decisions and/or action taken; preservation metadata logged, stored, and linked to pertinent digital objects.

B3. Preservation planning

A repository or archiving system must have current, sound, and documented preservation strategies in place and demonstrably implemented. It is not enough simply to preserve information. A repository must do so in accordance with predefined, documented, preservation policies and procedures, and it must have identified mechanisms to update those policies and procedures in response to changing technologies. Without such documentation, a repository cannot pass an audit even if its work is otherwise exemplary.

Documentation need not be particularly complex. It also does not need to prescribe in detail how a repository will deal with the unknown. For instance, a repository cannot be required to document how it will preserve a file format, or information semantics e.g. terminology, that has not yet been invented. But it may be expected to describe what it will do when first presented with an object in a format or using a terminology dictionary that it has not encountered before. It may not have strategies for every single kind of file within the repository (especially important for institutions acquiring and ingesting the product of Web harvesting/archiving activities), but it needs to be able to articulate organizational awareness of the diversity of information within the repository as well as plans or assertions about the preservation strategies that will or will not be employed against certain files. Organizational policy may be to reject the object or to investigate the feasibility of dealing with it, or the decision may depend on other factors, such as who offered the object or what information it contains.

A trusted digital repository cannot simply say what it will do; it must demonstrate its policies, practices, and procedures. This documentation should be explicit, comprehensive, current, and available. For a detailed discussion of preservation planning, as well as examples of demonstrable policies, procedures, and practices required, see Appendix 5: Preservation Planning & Strategies.

-- MarkConrad - 29 Nov 2007 Why is the phrase "or archiving system" added to this requirement and several of its sub-requirements?

B3.1 Repository has documented preservation strategies.

A repository or archiving system must have current, sound, and documented preservation strategies. These will typically address the degradation of storage media, the obsolescence of media drives, and the obsolescence of Representation Information (including formats), safeguards against accidental or intentional digital corruption. For example, if migration is the chosen approach to some of these issues, there also needs to be policy on what triggers a migration and what types of migration are expected for the solution of each preservation issue identified.

Evidence: Documentation identifying each preservation issue and the strategy for dealing with that issue.

B3.2 Repository has mechanisms in place for monitoring and notification when Representation Information (including formats) approaches obsolescence or is no longer viable.

For most repositories, the concern will be with the Representation Information (including formats) used to preserve information, which may include information on how to deal with a file format or software that can be used to render or process it. Sometimes the format needs to change because the repository can no longer deal with it. Sometimes the format is retained and the information about what software is needed to process it needs to change. In all cases, the repository must show that it has some active mechanism to warn of impending obsolescence. Obsolescence is determined largely in terms of the knowledge base of the designated community(ies). This requirement ensures that the preserved information remains understandable and usable by the designated community(ies). If the mechanism depends on an external registry, the repository must demonstrate how it uses the information from that registry.

Evidence: Subscription to a format registry service; subscription to a technology watch service; percentage of at least one staff member dedicated to monitoring technological obsolescence issues and practices of the designated community.

DavidGiaretta - I suggest we add here the phrase "for the Designated Community" because that concept was introduced in order to allow these sort of evaluations to be made with reference to something which can be specified rather than be left to be open and general.

B3.3 Repository has mechanisms to change its preservation plans as a result of its monitoring activities.

The repository must demonstrate or describe how it reacts to information from monitoring, which sometimes requires a repository to change how it deals with the material it holds in unexpected ways in ways that could not have been anticipated at an earlier stage. Plans as simple as migrating from format X to format Y when the registries show that format X is no longer supported are not sufficiently flexible—other events may have made format Y a bad choice. The repository must be prepared for changes in the external environment that may make its current plan (to migrate from X to Y in 10 years) a bad choice as the time to implement draws near. The repository should be able to show that it can revise long-range plans in light of changing circumstances.

Another possible response to information gathered by monitoring is for the repository to create additional Representation Information and/or PDI.

Evidence: Preservation planning policies tied to formal or information technology watch(es); preservation planning or processes that are timed to shorter intervals (e.g., not more than five years); proof of frequent preservation planning/policy updates.

B3.4 Repository can provide evidence of the effectiveness of its preservation planningactivities.

DavidGiaretta - perhaps this would be clearer if it said "...effectiveness of its preservation activities" - DONE

The repository should be able to demonstrate the continued preservation, including understandability, of its holdings over a number of years, given the age of the repository and its holdings.

This could be evaluated at a number of degrees and depends on the specificity of the designated community(ies). If a designated community is fairly broad, an auditor could represent the test subject in the evaluation. More specific designated communities could require significant efforts. If judgment must be exercised as to whether adequate efforts have been made, it must be justified in detail.

Evidence: Collection of appropriate preservation metadata; proof of usability of randomly selected digital objects held within the system; demonstrable track record for retaining usable digital objects over time.

B4. Archival storage & preservation/maintenance of AIPs

There is a minimal set of conditions for performing long-term preservation of AIPs. The system infrastructure (discussed in C1) must provide suitable services to allow higher-level repository (object management) functions operating on AIPs to perform their tasks reliably. But if the higher-level functions do not use these services, or do not use them properly, then preservation is not assured. The preservation of AIPs must follow the documented preservation strategies, typically including such topics as the use of migration, transformations, checksums, multiple copies, distributed storage, and tracking of processing history that might affect preservation confidence.

B4.1. Repository employs documented preservation strategies.

Documented preservation strategies include evidence of planning for strategies not yet employed against the repository’s digital objects. A repository is likely to employ multiple strategies. Different strategies may be employed by class (type) of digital object, and/or multiple strategies may be employed on a single object class. This will depend upon local repository policies and practices, though any such strategy decisions should be documented and should be based on sound community practice.

Minimally, documentation of preservation strategies must be included in repository policies and practices. Good repository practice also requires that preservation strategies employed against digital objects are recorded in the object’s preservation metadata. (See also B3.3.)

Evidence: Documentation of strategies and their appropriateness to repository objects; evidence of application (e.g., in preservation metadata); see B3.3.

B4.2. Repository implements/responds to strategies for archival object (i.e., AIP) storage and migration.

At least two aspects of the strategy must be acted upon: that which pertains to how AIPs are currently stored (including physical requirements, media requirements, location of copies, formats and metadata) and that which may require AIP migration of any form. For example, AIP migrations that result in transformations of content need to be tracked to allow subsequent users to understand the repository’s processing implications.

If a repository has not yet needed to carry out any sort of preservation strategy on AIP(s), it must demonstrate that its policy has not required it yet.

Evidence: Institutional technology and standards watch; demonstration of objects on which a preservation strategy has been performed; demonstration of appropriate preservation metadata for digital objects.

B4.3 Repository preserves the Content Information of archival objects (i.e., AIPs).

The repository must be able to demonstrate that the AIPs faithfully reflect what was captured during ingest and that any subsequent or future planned transformations will continue to preserve that aspect of the repository’s holdings.

One approach to this requirement assumes that the repository has a policy specifying that AIPs cannot be deleted at any time. This particularly simple and robust implementation preserves links between what was originally ingested, as well as new versions that have been transformed or changed in any way. Depending upon implementation, these newer objects may be completely new AIPs or merely updated AIPs. Either way, persistent links between the ingested object and the AIP should be maintained.

Evidence: Policy documents specifying treatment of AIPs and whether they may ever be deleted; ability to demonstrate the chain of AIPs for any particular digital object or group of objects ingested; workflow procedure documentation.

B4.4 Repository actively monitors integrity of archival objects (i.e., AIPs).

In OAIS terminology, this means that the repository must have Fixity Information for AIPs and must make some use of it. At present, most repositories deal with this at the level of individual information objects by using a checksum of some form, such as MD5. In this case, the repository must be able to demonstrate that the Fixity Information (checksums, and the information that ties them to AIPs) are stored separately or protected separately from the AIPs themselves, so that someone who can maliciously alter an AIP would not likely be able to alter the Fixity Information as well. A repository should have logs that show this check being applied and an explanation of how the two classes of information are kept separate.

AIP integrity also needs to be monitored at a higher level, ensuring that all AIPs that should exist actually do exist, and that the repository does not possess AIPs it is not meant to. Checksum information alone will not be able to demonstrate this.

Evidence: Logs of fixity checks (e.g., checksums); documentation of how AIPs and Fixity information are kept separate.

-- KatiaThomaz - 10 May 2007 - It lacks “repository actively monitors authenticity, storage and readability of archival objects” (see NESTOR CCTDR 7.2, 10.3).

-- KatiaThomaz - 17 Sep 2007 - Remember the archival object context (technological, administrative, ambiental etc.) can change and so the authenticity, storage and readability

-- KatiaThomaz - 24 Sep 2007 - B1.3 states "Repository has mechanisms to authenticate the source of all materials". After this repository only monitors the integrity, ok?

-- KatiaThomaz - 24 Sep 2007 - I insist that "preserve physical presence" is necessary. I think Bullock's nine actions can help us to cover all the issues, they are: I - Fixing the object as a discrete whole; II – Preserving the physical presence; III - Preserving the content; IV - Preserving the presentation; V - Preserving the functionality; VI - Preserving the authenticity; VII - Locating and referring to the original object over time; VIII - Preserving provenance; and IX - Preserving context. [Bullock, A. (1999). Preservation of digital information: Issues and current status. Ottawa: National Library of Canada. Retrieved November 25, 2003, from]

B4.5 Repository has contemporaneous records of actions and administration processes that are relevant to preservation (Archival Storage).

These records must be created on or about the time of the actions they refer to and are related to actions associated with archival storage. The records may be automated or may be written by individuals, depending on the nature of the actions described. Where community or international standards are used, such as PREMIS (2005), the repository must demonstrate that all relevant actions are carried through. Evidence: Written documentation of decisions and/or action taken; preservation metadata logged, stored, and linked to pertinent digital objects.

B5. Information management

A critical component of any repository is its information management functionality. Regardless of technical composition and regardless of whether it is considered a “light” repository or a “dark” one— holding material for access by future generations—the system needs to be able to store, track and use metadata which supports the core functionality of the digital repository. The OAIS (2002) describes this functionality within Data Management, but, practically, this information is critical to and is generated within other digital repository functions such as ingest, archival storage, preservation planning, and access. For that reason, this section, Information Management, addresses the remaining needs associated with descriptive metadata.

Regardless of system, descriptive information (metadata) will be acquired and maintained for access and retrieval. If people cannot find what they want, the repository is not serving the needs of its users. The minimum metadata requirements for data management may be very basic. In most cases, the minimum requirement for discovery may be nothing more than an identifier a designated community uses to request a deposited object, such as a catalog number or an archival reference. People also need to know whether they are permitted to get a usable copy of it and how.

A repository’s minimum descriptive metadata requirements must match the minimum needs of the repository’s designated community(ies). This does not mean the repository needs to be able to respond to every one of its users’ requests for additional catalog information. Rather, it must assess what it can provide to a representative member of its designated community(ies), based on utility and cost. If the repository serves multiple communities, each interested in different segments of its holdings, then the minimum requirements may vary from AIP to AIP. If a repository holds both digital films and digital music, the minimum descriptive elements for film and music will differ.

Descriptive information can include much more than the narrative description that might be familiar to the user of a traditional library or archive catalog. It may also include any information that the potential user may find helpful in assessing the appropriateness and ease of use of an object, including indications of types of tools needed for use. If a repository’s holdings vary greatly in size and the larger objects are not suitable for downloading over a network connection, for instance, information about size enables a user to choose an optimum delivery method, such as a tape to be delivered by mail. Or a repository’s holdings may require special software to be available to the user to allow an object to be interpreted. Users must be able to determine this in advance, rather than possibly paying to acquire material only to discover that they do not have the tools to use it.

A repository can address this need in the more general information it makes available to its users, rather than placing specific information in the descriptive information for each AIP. For instance, a repository that holds only PDF files can:

  • State in the information for each AIP that it is a PDF file.
  • Have general information on how to use the repository that states that you will need a PDF reader to use its holdings.
  • Define its designated community(ies) as people with access to a PDF reader.

It is the repository’s job to ensure that each and every stored object has descriptive information associated with it. This audit checklist does not specify how the repository does this, only that it must be clear how it is done. The repository may shift the burden entirely to the producers of information by requiring that say that material offered to the repository must contain a minimum amount of metadata to enable storage of descriptive information. The repository may take on the task of producing the information itself. Or it may fill in the gaps in what producers provide—using their metadata when it is sufficient, and adding metadata when it is not. Whichever the repository does, it must set out in advance the minimum metadata requirements that enable material to be discovered and identified again.

-- KatiaThomaz - 10 May 2007 - New item for “repository captures or creates minimum packaging metadata and ensures that it is associated with the archived object (i.e., AIP)” (see OAIS RM).

  • DavidGiaretta - I would have thought that this is implied by the AIP definition, but it may be a good idea to state this point explicitly.
    • KatiaThomaz - Now, I dont´t know if they mean descriptive metadata = packaging information + descriptive information, but I think it must be clear.

-- JohnGarrett - 17 Sep 2007 - Standards often have specific understandings that use of certain verbs (must, shall, may, etc.) introduce requirements or make actions suggested or optional. Do we intend to create requirements or make some actions optional in these introductions to sections? I don't think we do, but when we get to a standards document we probably need to mention that in "How to read document" section.

B5.1 Repository articulates minimum metadata requirements to enable the designated community to discover and identify material of interest.

DavidGiaretta - at several places there is a mention of "...minimum xxx...". Would it be clearer if instead we said " least minimum xxx...", otherwise in principle these metrics could be mis-interpreted!

  • KatiaThomaz - I agree with David. It must be clear.
  • JohnGarrett - I actually think we should drop word minimum. In any case it is only minimum in the sense that it is the minimum amount that the community is willing to accept.

-- JohnGarrett - 17 Sep 2007 - Should we break this into 2 items - one enabling identification and another enabling discovery?

-- BarbaraSierman - 24 Sep 2007 I think this is a good suggestion, as these are two different things.

-- KatiaThomaz - 24 Sep 2007 - I think we shouldn't break into two items. One relates to another.

Retrieval metadata is distinct from metadata that describes what has been found. For example, in a library we might say that a book’s title is mandatory, but its publisher is not, because people generally search on the title.

A repository does not necessarily have to satisfy every possible request, but must be able to deal with the types of request that will come from a typical user from the designated community(ies). The minimum requirements must be articulated. The minimum may be nothing more than an identifier the designated community(ies) would know and use to request a deposited object.

Evidence: Policy regarding minimum Descriptive metadata; persistent identifier/locator associated with AIP. -- BarbaraSierman - 24 Sep 2007 The evidence documents should be available for different kind of objects, as the set of descriptive metadata may be different for various kinds of objects (journals, audio, film, art etc.). Is it already possible to suggest which kind of persistent identifier is used in certain "designated communities"?

B5.2 Repository captures or creates minimum descriptive metadata and ensures that it is associated with the archived object (i.e., AIP).

The repository has to show how it gets its required metadata. Does it require the producers to provide it (refusing a deposit that lacks it) or does it supply some metadata itself during ingest?

Associating the metadata with the object is important, though it does not require a one-to-one correspondence, and metadata need not necessarily be stored with the AIP. Hierarchical schemes of description allow some descriptive elements to be associated with many items. The association should be unbreakable—it must never be lost even if other associations are created.

Evidence: Descriptive metadata; persistent identifier/locator associated with AIP; system documentation and technical architecture; depositor agreements; metadata policy documentation, incorporating details of metadata requirements and a statement describing where responsibility for its procurement falls; process workflow documentation.

B5.3 Repository can demonstrate that referential integrity is created between all archived objects (i.e., AIPs) and associated descriptive information.

Every AIP must have some descriptive information and all descriptive information must point tobe associated with at least one AIP, such that the integrity of the reference can be validated. This should be an easy requirement to satisfy and is a prerequisite for the next one.

-- JohnGarrett - 17 Sep 2007 - Isn't it possible to create descriptive information before the AIPs are in the archive? Or create a descriptive scheme with enumerated values of some parameters where there are not yet AIPs in the archive with those values? -- BarbaraSierman - 24 Sep 2007 Should not the term "all descriptive information" be more precise, as in B5.2 it is stated that the place of the descriptive metadata where they are stored, is not defined but up to the repository. It can be in a library catalogue with other descriptive metadata of other kinds of (non-digital) material. So it should say something like the descriptive metadata related to the objects stored.

Evidence: Descriptive metadata; persistent identifier/locator associated with AIP; documented relationship between AIP and metadata; system documentation and technical architecture; process workflow documentation.

B5.4 Repository can demonstrate that referential integrity is maintained between all archived objects (i.e., AIPs) and associated descriptive information.

Particular attention must be paid to operations that affect AIPs and their identifiers and how integrity is maintained during these operations. There may be times, depending on system design, when the repository cannot demonstrate referential integrity because some system component is out of action. However, repositories, must implement procedures that let them know when referential integrity is temporarily broken and ensure that it can be restored.

Evidence: Log detailing ongoing monitoring/checking of referential integrity, especially following repair/modification of AIP; legacy descriptive metadata; persistence of identifier/locator; documented relationship between AIP and metadata; system documentation and technical architecture; process workflow documentation.

MarkConrad - 22 May 2007 Do these items adequately cover the referential integrity of an AIC to the corresponding AIPs?

  • DavidGiaretta - B2.11 refers to the completeness of an AIP (which includes AICs and AIUs) but perhaps we are missing something about the continued integrity of the collection. IN fact there is also an issue to do with an expanding collection -= how does one demonstrate completeness at any point?

-- JohnGarrett - 17 Sep 2007 - Is there a need to add checklist items for restricted access to and security of descriptive metadata?

B6. Access management

It must be understood that the capabilities and sophistication of the access system will vary depending on the repository’s designated community(ies) and the access mandates of the repository. Because of the variety of repositories, archives, and access mandates, these criteria may be subject to questions about applicability and interpretation at a local level. For in-depth discussion of access management issues, see Appendix 6: Understanding Digital Repositories & Access Functionality.

Repositories with a mandate to provide current access must be able to produce Dissemination Information Packages (DIPs) that meet the needs of their users or are appropriate to the levels of access they offer. “Dark” archives or national archives that may have mandates restricting access for a certain number of years will produce most DIPs for internal requirements, such as performing migrations, rather than for access. In any case, any repository must be able to produce a DIP, however primitive and whatever its purpose.

These requirements ensure that access is implemented according to the repository’s stated policies:

  • B6.1 to B6.4 are primarily concerned with access conditions and actions related to the designated community(ies);
  • B6.5 and B6.6 are primarily concerned with access security, with a focus on internal (staff) access;
  • B6.7 to B6.9 ensure that the access function is implemented correctly. Access should always deliver what is required, or else make clear that it is not possible for whatever reason. Timeliness may be measured in seconds or weeks, since access may be an online function or a postal function or may be mediated through some other mechanism or a combination of them.
  • B6.10 adds a specific requirement over and above the need to simply provide access to a repository’s holdings. For the repository to be trusted, it must be able to provide a copy of material that can be traced back to originals.

-- KatiaThomaz - 10 May 2007 - New item for “repository ensures access to digital objects by its designated community” (see NESTOR CCTDR 2.1)
-- MarkConrad - 28 Sep 2007 This is covered by B. 6.1. -- DavidGiaretta - 01 Oct 2007 B 6.1 allows the possibility that the Designated COmmunity does not actually have access e.g. data which is currently secret right now, therefore there is no access, but it will become available in a few years and should be understandable then.

-- KatiaThomaz - 10 May 2007 - New item for “repository defines its DIPs” (see NESTOR CCTDR 11.1)
-- MarkConrad - 28 Sep 2007 This is at least partially covered by B. 6.8.

-- KatiaThomaz - 10 May 2007 - New item for “repository ensures transformation of AIPs into DIPs” (see NESTOR CCTDR 11.2).

  • An issue which several colleagues have spoken about is that of being able to demonstrate authenticity of the information. Perhaps when we speak about transfomrations we need to be clear that one should be able, if requested, to follow e.g. an audit trail in order to demonstrate authenticity.
-- MarkConrad - 28 Sep 2007 This is already covered in B. 6.10!

B6.1 Repository documents and communicates to its designated community what access and delivery options are available.

Repository policies should document the various aspects of access to and delivery of the preserved information. Generally, the designated community(ies) should know the policies or at least the consequences of them. The users should know what they can ask for, when, and how, and what it costs, among other things. See Appendix 6: Understanding Digital Repositories & Access Functionality for an in-depth review of digital repository access requirements.

Repositories might have to deal with a single, homogeneous community or with multiple or disparate communities. Different policies might be needed for different communities as well as for different collection types.

Evidence: Public Versions of access policies available to various designated communities; delivery policies; fee policies.

B6.2 Repository has implemented a policy for recording all access actions (includes requests, orders etc.) that meet the requirements of the repository and information producers/depositors.

A repository need only record the actions that meet the requirements of the repository and its information producers/depositors. This may mean that little or no information is recorded about access. That is acceptable if the repository can demonstrate that it does not need to do more. Some repositories may want information about what is being accessed, but not about the users. Others may need much more detailed information about access. A policy should be established and implemented that relates to demonstrable needs. Are these figures being monitored? Are statistics produced and made available?

Evidence: Access policies; use statements; access logs.

B6.3 Repository ensures that agreements applicable to access conditions are adhered to.

The repository must be able to show what producer/depositor agreements apply to which AIPs and must validate user identities in order to ensure that the agreements are satisfied. Although it is easy to focus on denying access when considering conditions of this kind (that is, preventing unauthorized people from seeing material), it is just as important to show that access is granted when the conditions say it should be.

Access conditions are often just about who is allowed to see things (including both data and metadata items), but they can be more complex. They may involve limits on quantities—all members of a certain community are permitted to access 10 items a year without charge, for instance. Or they may involve limits on usage or type of access—some items may be viewed but not saved for later reuse, or items may only be used for private research but not commercial gain, for instance.

Various scenarios may help illustrate what is required:

If a repository’s material is all open access, the repository can simply demonstrate that access is truly available to everyone.

If all material in the repository is available to a single, closed community, the repository must demonstrate that it validates that users are members of this community, perhaps by requesting some proof of identity before registering them, or just by restricting access by network addresses if the community can identified in that manner. It should also demonstrate that all members of the community can indeed gain access if they wish.

If different access conditions apply to different AIPs, the repository must demonstrate how these are realized.

If access conditions require users to make some declaration before receiving DIPs, the repository must show that the declarations have been made. These might be signed forms, or evidence that a statement has been viewed online and a button clicked to signify agreement. The declarations might involve nondisclosure or agreement to no commercial use, for instance.

Evidence: Access policies; logs of user access and user denials; access system mechanisms that prevent unauthorized actions (such as save, print, etc.); user compliance agreements.

B6.4 Repository has documented and implemented access policies (authorization rules, authentication requirements) consistent with deposit agreements for stored objects.

User credentials are only likely to be relevant for repositories that serve specific communities or that have access restrictions on some of their holdings. A user credential may be as simple as the IP address from which a request originates, or may be a username and password, or may be some more complex and secure mechanism. Thus, while this requirement may not apply to some repositories, it may require very formal validation for others. The key thing is that the access and delivery policies are reflected in practice and that the level of validation is appropriate to the risks of getting validation wrong. Some of the requirements may emerge from agreements with producers/depositors and some from legal requirements.

Repository staff will also need to access stored objects occasionally, whether to complete ingest functions, perform maintenance functions such as verification and migration, or produce DIPs. The repository must have policies and mechanisms to protect stored objects against deliberate or accidental damage by staff (see C3.3).

Evidence: Access validation mechanisms within system; documentation of authentication and validation procedures.

B6.5 Repository access management system fully implements access policy.

The repository must demonstrate that all access policies are implemented. Access may be managed partly by computers and partly by humans—checking passports, for instance, before issuing a user ID and password may be an appropriate part of access management for some institutions.

Evidence: Logs and audit trails of access requests; information about user capabilities (authentication matrices); explicit tests of some types of access.

B6.6 Repository logs all access management failures, and staff review inappropriate “access denial” incidents.

A repository should have some automated mechanism to note anomalous or unusual denials and use them to identify either security threats or failures in the access management system, such as valid users being denied access. This does not mean looking at every denied access. This requirement does not apply to repositories with unrestricted access.

Evidence: Access logs; capability of system to use automated analysis/monitoring tools and generate problem/error messages; notes of reviews undertaken or action taken as result of reviews.

B6.7 Repository can demonstrate that the process that generates the requested digital object(s) (i.e., DIP) is completed in relation to the request.

If a user expects a set, the user should get the whole set. If the user expects a file, the user should get the whole file. If the user’s request cannot be satisfied, the user should be told this; for instance, resource shortages may mean a valid request cannot be satisfied. Acceptable scenarios include:

The user receives the complete DIP asked for and it is clear to the user that this has happened.

The user is told that the request cannot be satisfied. Part of the request cannot be satisfied, the user receives a DIP containing the elements that can be provided, and the system makes clear that the request is only partially satisfied.

Unacceptable scenarios include:

The request can only be partially satisfied and a partial DIP is generated, but it is not clear to the user that it is partial.

The request is delayed indefinitely because something it requires, such as access to a particular AIP, is not available, but the user is not notified nor is there any indication as to when the conflict will be resolved.

The user is told the request cannot be satisfied, implying nothing can be delivered, but actually receives a DIP, and is left unsure of its validity or completeness.

Evidence: System design documents; work instructions (if DIPs involve manual processing); process walkthroughs; logs of orders and DIP production; test accesses to verify delivery of appropriate digital objects.

B6.8 Repository can demonstrate that the process that generates the requested digital object(s) (i.e., DIP) is correct in relation to the request.

The right material should be delivered and appropriate transformations should be applied, if necessary to generate the DIP. A simple example is that if the repository stores TIFF images but delivers JPEGS, the conversion should be shown to be correct to whatever standards seem appropriate. If the repository offers delivery as JPEG or PNG, the user should receive the format requested. Many repositories may apply more complex transformations to generate DIPs from AIPs.

Evidence: System design documents; work instructions (if DIPs involve manual processing); process walkthroughs; logs of orders and DIP production.

B6.9 Repository demonstrates that all access requests result in a response of acceptance or rejection.

Eventually a request must succeed or fail, and there must be limits on how long it takes for the user to know this. Access logs are the simplest way to demonstrate response time, even if the repository does not retain this information for long. However, a repository can demonstrate compliance if it can show that all failed requests result in an error log of some sort, and that requests are bounded in duration in some way.

Evidence: System design documents; work instructions (if DIPs involve manual processing); process walkthroughs; logs of orders and DIP production.

B6.10 Repository enables the dissemination of authentic copies of the original or objects traceable to originals.

Part of trusted archival management deals with the authenticity of the objects that are disseminated. A repository’s users must be confident that they have an authentic copy of the original object, or that it is traceable in some auditable way to the original object. This distinction is made because objects are not always disseminated in the same way, or in the same groupings, as they are deposited. A database may have subsets of its rows, columns, and tables disseminated so that the phrase “authentic copy” has little meaning. Ingest and preservation actions may change the formats of files, or may group and split the original objects deposited.

The distinction between authentic copies and traceable objects can also be important when transformation processes are applied. For instance, a repository that stores digital audio from radio broadcasts may disseminate derived text that is constructed by automated voice recognition from the digital audio stream. Derived text may be imperfect but useful to many users, though these texts are not authentic copies of the original audio. Producing an authentic copy means either handing out the original audio stream or getting a human to verify and correct the transcript against the stored audio.

This requirement ensures that ingest, preservation, and transformation actions do not lose information that would support an auditable trail between the original deposited object and the eventual disseminated object. For compliance, the chain of authenticity need only reach as far back as ingest, though some communities, such as those dealing with legal records, may require chains of authenticity that reach back further.

A repository should be able to demonstrate the processes to construct the DIP from the relevant AIP(s). This is a key part of establishing that DIPs reflect the content of AIPs, and hence of original material, in a trustworthy and consistent fashion. DIPs may simply be a copy of AIPs, or may result from a simple format transformation of an AIP. But in other cases, they may be derived in complex ways from a large set of AIPs. A user may request a DIP consisting of the title pages from all e-books published in a given period, for instance, which will require these to be extracted from many different AIPs. A repository that allows requests for such complex DIPs will need to put more effort into demonstrating how it meets this requirement than a repository that only allows requests for DIPs that correspond to an entire AIP.

A repository is not required to show that every DIP it provides can be verified as authentic at a later date; it must show that it can do this when it is required at the time of production of the DIP. The level of authentication is to be determined by the designated community(ies). This requirement is meant to enable high levels of authentication, not to impose it on all copies, since it may be an expensive process.

Evidence: System design documents; work instructions (if DIPs involve manual processing); process walkthroughs; production of a sample authenticated copy; documentation of community requirements for authentication.

-- KatiaThomaz - 10 May 2007 -- DonaldSawyer - 20 Jun 2007 -- SimonLambert - 21 Jun 2007

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Topic revision: r41 - 2007-12-17 - JohnGarrett
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