A type of Package Description that is specialized to provide information about an Archival Information Unit for use by Access Aids.

Digital Object or physical objectinstantiating or embodying an Intellectual Entity.A Representation that is a Digital Object is theset of stored Files and StructuralMetadata needed to provide a complete rendition of the Intellectual Entity.

Process of copying a Digital Object sothat the copy is bit-wise identical to the original. Media Migration and MediaRefreshment are specific types of Replication.

Statement about an association between instances of Entities.

To make a Digital Object perceptible to a user, by displaying (forvisual materials), playing (for audio materials), or other means appropriate tothe Format of the Digital Object.

See Media Refreshment.

Specification for a particular implementation of a Format.For example, GeoTIFF is a profile of TIFF.

Any loss in functionality or change in the look and feel of a Digital Object resulting from the preservationprocesses and procedures implemented by a PreservationRepository. (See also the definition supplied by the National Library ofAustralia http://www.nla.gov.au/preserve/pmeta.html#14.)

Information a PreservationRepository uses to support the digital preservation process.

Repository that, either as its sole responsibility or as one of multiple responsibilities,undertakes the long-term preservation of the DigitalObjects in its custody.

Period in the life cycle of a Digital Object before it is Ingested into a Preservation Repository.

See Digital Object.

Agreement between a Rights holder and a Preservation Repository, allowing the Preservation Repository to undertake some action.

Form of Migration in which a version of a Digital Object is created ina new Format with properties more conducive topreservation treatment. Normalization is often implemented as part of the Ingestprocess.

Set of names in which all names are unique. (From FOLDOC http://foldoc.org/namespace.)

Preservation strategy in which a Transformationcreates a version of a Digital Object in adifferent Format, where the new Formatis compatible with contemporary software and hardware environments. Ideally,Migration is accomplished with as little loss of content, formatting andfunctionality as possible, but the amount of information loss will vary dependingon the Formats and content types involved. Also called"format migration" and "forward migration." Migration and Media Migration are used inpreference to the definition of "digital migration" in the OAIS Reference Model. OAIS defines digital migration as the"transfer of digital information, while intending to preserve it, within the OAIS. It is distinguished from transfers in general by three attributes 1) afocus on the preservation of the full information content; 2) a perspective that the new archival implementation of the information is a replacement forthe old; and 3) an understanding that full control and responsibility over all aspects of the transfer resides with the OAIS."

Process by which a Message Digestis created for a Digital Objectresiding in a Preservation Repository.See also Fixity Check.

Result of applying a one-way hash function to a message. A MessageDigest is a value that is shorter than the message, but would be different ifthe message were changed by even one character. (FromBBN Technologies http://www.bbn.com/utility/glossary/M.)"Message" here means any string of bits, such as a File or Bitstream. A Message Digest is ofteninformally called a "checksum".

Form of Replication, in which a DigitalObject is copied onto a different unit of storage of the same or similar medium as the original. Note MediaRefreshment is used in preference to the definition of "refreshment" in the OAISReference Model. OAIS defines refreshment as a "Digital Migration where theeffect is to replace a media instance with a copy that is sufficiently exact that all Archival Storage hardware and software continues to run as before."

Form of Replication, in which a Digital Object is copiedonto a different type of digital storage medium because the original medium isin danger of obsolescence.

Feature of a Digital Object intended toinhibit access, copying, Dissemination, or Migration. Common Inhibitors are Encryptionand password protection.

Coherent set of content that is described as a unit for example, abook, a map, a photograph, a serial. An Intellectual Entity can include otherIntellectual Entities; for example, a Web Site caninclude a Web Page, a Web Pagecan include a photograph. An Intellectual Entity may have one or more Representations.

Process of adding objects to a PreservationRepository’s storage system. In the context of OAIS, Ingest includesservices and functions that accept Submission Information Packages (SIP) fromproducers, and transform them into one or more Archival Information Packages(AIP) for long-term retention.

See Migration.

See Migration.

Relative size, scale, level of detail, or depth of penetration thatcharacterizes an object or activity. "Level of granularity" maybe used to refer to the level of focus in a hierarchy or to refer to thelevel of specificity of description.

Specific, pre-established structure for the organization of a File, Bitstream, or Filestream.

Property of a Digital Object thatindicates it has not changed between two points in time.

Process of verifying that a File or Bitstream has not been changedduring a given period. A common Fixity Check method is to compute a Message Digest ("hash") at one point and recalculatethe Message Digest at a later point; if thedigests are identical, the object has not been altered.

Embedded Bitstream that can be transformedinto a standalone File without adding any additionalinformation for example, a TIFF image embedded within a tar File, or an encodedEPS within an XML File.

Named and ordered sequence of Bytes that is known by an operating system. A File can be zero or more Bytes long, has access permissions, and has File system statistics such as size and last modificationdate. A File also has a Format.

Property that Semantic Units in thePREMIS Data Dictionary may be supplemented by externally defined Semantic Units, or replaced by moregranular Semantic Units, so long as there isno conflict in their definition and use.

Preservation-relevant action that involves at least one Digital Object and/or Agentknown to the Preservation Repository.

Abstraction for a set of "things" (environments, Events, etc.) described by the sameproperties. The PREMIS data model defines four types of Entities Objects, Agents, Rights,and Events.

Technology supporting a Digital Object in some way (e.g. byrendering or executing it). Environments can consist of software, hardware, ora combination of both. Environments can be described as Intellectual Entities and captured andpreserved in the PreservationRepository as Representations, Files and/or Bitstreams.

Process of employing any procedure used in cryptography to convertplaintext into ciphertext (encrypted message) in order to prevent any but theintended recipient from reading that data. Schematically, there are two classesof encryption primitives public-key cryptography andprivate-key cryptography; they are generally used complementarily. Public-keyencryption algorithms include RSA; private-key algorithms include the obsolescentData Encryption Standard, the Advanced Encryption Standard, as well as RC4.(From FOLDOC http://foldoc.org/encryption.)

Preservation strategy for overcoming technological obsolescence ofhardware and software by developing techniques for imitating obsolete systemson future generations of computers. (From DPC http://www.dpconline.org/advice/preservationhandbook/introduction/definitions-and-concepts?q=definitions.)

Process of determining that a decrypted digital signature matches anexpected value when the correct keys, algorithms, and parameters have been used. Validation confirmsthe originator and Fixity of the signed Digital Object.

Process of retrieving a Digital Objectfrom the Preservation Repository’sarchival storage and making it available to users. In the context of OAIS,Dissemination involves transforming one or more Archival Information Packages (AIP)into a Dissemination Information Package (DIP) and making it available in aform suitable for the Preservation Repository’s Designated Community.

Value computed with a cryptographic algorithm and appended to datain such a way that any recipient of the data can use the signature to verifythe data's origin and integrity. The electronic counterpart of a handwrittensignature on a hard copy document. (From BBN Technologies http://www.bbn.com/utility/glossary/D.)

Documentation of processes in a DigitalObject’s life cycle. Digital Provenance typically describes Agentsresponsible for the custody and stewardship of DigitalObjects, key Events that occur over the course of the Digital Object’s life cycle, and other informationassociated with the Digital Object’s creation,management, and preservation.

See Migration.

Discrete unit of information in digital form. A Digital Object can be an Intellectual Entity, Representation,File, Bitstream, or Filestream. Note that the PREMIS definition of DigitalObject differs from the definition commonly used in the digital library community,which holds a digital object to be a combination of identifier, metadata, anddata.

Metadata that serves the purposes of discovery (how one finds aresource), identification (how a resource can be distinguished from other,similar resources), and selection (how to determine that a resource fills a particular need). (From Caplan, Metadata Fundamentals for All Librarians, ALA Editions, 2003)

Relationship where one Digital Objectrequires another Object to support its function,delivery, or the coherence of its content.

Process of removing a Digital Objectfrom repository storage.

Process of reversing the effects of data Compression.(From FOLDOC http://foldoc.org/decompress.)

Process of employing any procedure used in cryptography to convertciphertext (encrypted data) into plaintext. (From FOLDOC http://foldoc.org/decryption.)

See File.

See Digital Object.

Process of removing a Digital Objectfrom the inventory of a PreservationRepository.

Process of coding data to save storage space or transmission time.Although data is already coded in digital form for computer processing, it canoften be coded more efficiently (using fewer bits). For example, run-lengthencoding replaces strings of repeated characters (or other units of data) witha single character and a count. There are many Compression algorithms andutilities. Compressed data must be Decompressedbefore it can be used. (From FOLDOC http://foldoc.org/compression.)

In the Data Dictionary, a Semantic Unitused to group other related Semantic Units. AContainer Semantic Unit takes no value of its own.

Semantic Units that most Preservation Repositories will need to knowin order to support the digital preservation process. Core PreservationMetadata should be independent of factors such as specific preservationstrategy, type of archived content, and institutional context.

See Compound Object.

Digital Object composed of multiple Files for example, a Web Page composedof text and image Files.

Policies and other restrictions, guidelines, and proceduresgoverning the administration and operation of a Preservation Repository.

A component in the machine data hierarchy usually larger than a bitand smaller than a word now most often eight bits and the smallest addressableunit of storage. A Byte typically holds one character. (From FOLDOC http://foldoc.org/byte.)

Process by which a PreservationRepository actively obtains Digital Objectsfor long-term retention, for example, a harvesting program that collects Web Sites. Note that the Capture process precedes the Ingest process.

See Message Digest.

Property of a Semantic Unit indicating that the Semantic Unit is recorded/coded in such a way as to be processed automatically.

Actor (human, machine, or software) associated with one or more Events and or Rights associated with a Digital Object. Machine or software Agents can themselves be captured as a DigitalObject.

Aspect of a Digital Object that doesnot meet the specification for the Digital Object.

Property that a Digital Object is what it purports to be; that is, that the integrity of both the source and the content of the Digital Objectcan be verified.

Preservation strategy in which the sole objective is to ensure thata Digital Object remains fixed (unaltered) andviable (readable from media). No effort is made toensure that the Digital Object remains renderableor interpretable by contemporary technology.

Contiguous or non-contiguous data within a File that has meaningfulcommon properties for preservation purposes. A Bitstream cannotbe transformed into a standalone File without theaddition of File structure (headers, etc.) and/or reformatting the Bitstream inorder to comply with some particular Format. Note thatthis definition is more specific than the common definition of "bitstream" usedin computer science.

A session initiated by the Consumer with the Archive during which the Consumer will use the Archive Finding Aids to identify and investigate potential holdings of interest.

The Representation Information that further describes the meaning beyond that provided by the Structure Information.

The Representation Information that imparts meaning about how other information is organized. For example, it maps bit streams to common computer types such as characters, numbers, and pixels and aggregations of those types such as character strings and arrays.

Relationship between Digital Objects whereone Object is the result of a Transformationperformed on the other Object.

The agreement reached between an OAIS and the Producer that specifies a data model, and any other arrangements needed, for the Data Submission Session. This data model identifies format/contents and the logical constructs used by the Producer and how they are represented on each media delivery or in a telecommunication session.

An Information Package that is delivered by the Producer to the OAIS for use in the construction or update of one or more AIPs and/or the associated Descriptive Information.

The plan of how and when the management, ownership and/or control of the OAIS holdings will be transferred to a subsequent OAIS in order to ensure the continued effective preservation of those holdings.

A Digital Migration in which there is an alteration to the Content Information or PDI of an Archival Information Package. For example, changing ASCII codes to UNICODE in a text document being preserved is a Transformation.

An Information Property the preservation of the value of which is regarded as being necessary but not sufficient to verify that any Non-Reversible Transformation has adequately preserved information content. This could be important as contributing to evidence about Authenticity. Such an Information Property is dependent upon specific Representation Information, including Semantic Information, to denote how it is encoded and what it means. (The term ‘significant property’, which has various definitions in the literature, is sometimes used in a way that is consistent with its being a Transformational Information Property).

An application that allows authorized users to retrieve the Content Information and PDI described by the Package Description.

A Transformation in which the new representation defines a set (or a subset) of resulting entities that are equivalent to the resulting entities defined by the original representation. This means that there is a one-to-one mapping back to the original representation and its set of base entities.

A type of software that displays Representation Information of an Information Object in forms understandable to humans.

The information that is used as an identifier for the Content Information. It also includes identifiers that allow outside systems to refer unambiguously to a particular Content Information. An example of Reference Information is an ISBN.

A framework for understanding significant relationships among the entities of some environment, and for the development of consistent standards or specifications supporting that environment. A reference model is based on a small number of unifying concepts and may be used as a basis for education and explaining standards to a non-specialist.

A Digital Migration where the effect is to replace a media instance with a copy that is sufficiently exact that all Archival Storage hardware and software continues to run as before.

A Digital Migration in which there is an alteration in the Packaging Information of the AIP.

The role played by those persons or client systems that provide the information to be preserved. This can include other OAISes or internal OAIS persons or systems.

The information that documents the history of the Content Information. This information tells the origin or source of the Content Information, any changes that may have taken place since it was originated, and who has had custody of it since it was originated. The Archive is responsible for creating and preserving Provenance Information from the point of Ingest; however, earlier Provenance Information should be provided by the Producer. Provenance Information adds to the evidence to support Authenticity.

The set of Representation Information that fully describes the meaning of a Data Object. Representation Information in digital forms needs additional Representation Information so its digital forms can be understood over the Long Term.

The information that maps a Data Object into more meaningful concepts. An example of Representation Information for a bit sequence which is a FITS file might consist of the FITS standard which defines the format plus a dictionary which defines the meaning in the file of keywords which are not part of the standard. Another example is JPEG software which is used to render a JPEG file; rendering the JPEG file as bits is not very meaningful to humans but the software, which embodies an understanding of the JPEG standard, maps the bits into pixels which can then be rendered as an image for human viewing.

A Digital Migration where there is no change to the Packaging Information, the Content Information, and the PDI. The bits used to represent these Information Objects are preserved in the transfer to the same or new media instance.

The information which is necessary for adequate preservation of the Content Information and which can be categorized as Provenance, Reference, Fixity, Context, and Access Rights Information.

The OAIS functional entity which provides the services and functions for monitoring the environment of the OAIS and which provides recommendations and preservation plans to ensure that the information stored in the OAIS remains accessible to, and understandable by, and sufficiently usable by, the Designated Community over the Long Term, even if the original computing environment becomes obsolete.

An object (such as a moon rock, bio-specimen, microscope slide) with physically observable properties that represent information that is considered suitable for being adequately documented for preservation, distribution, and independent usage.

An application that assists the Consumer in discovering the cost of, and in ordering, AIPs of interest.

Representation Information which cannot easily be classified as Semantic or Structural. For example software, algorithms, encryption, written instructions and many other things may be needed to understand the Content Data Object, all of which therefore would be, by definition, Representation Information, yet would not obviously be either Structure or Semantics. Information defining how the Structure and the Semantic Information relate to each other, or software needed to process a database file would also be regarded as Other Representation 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.

The information intended for use by Access Aids.

A specialization of the Collection Description that describes the collection as a whole.

The community which would be served by the Archive outside of the context of Federated Archives.

A period of time long enough for there to be concern about the impacts of changing technologies, including support for new media and data formats, and of a changing Designated Community, on the information being held in an OAIS. This period extends into the indefinite future.

The act of maintaining information, Independently Understandable by a Designated Community, and with evidence supporting its Authenticity, over the Long Term.

The role played by those who set overall OAIS policy as one component in a broader policy domain, for example as part of a larger organization.

An Associated Description that describes a member of a collection.

Data about other data.

A Transformation which cannot be guaranteed to be a Reversible Transformation.

An Archive, consisting of an organization, which may be part of a larger organization, of people and systems, that has accepted the responsibility to preserve information and make it available for a Designated Community. It meets a set of responsibilities, as defined in section 4, that allows an OAIS Archive to be distinguished from other uses of the term ‘Archive’. The term ‘Open’ in OAIS is used to imply that this Recommendation and future related Recommendations and standards are developed in open forums, and it does not imply that access to the Archive is unrestricted.

An agreement between the Archive and the Consumer in which the physical details of the delivery, such as media type and format of Data, are specified.

A set of information, incorporated by a person or system, that allows that person or system to understand received information.

An extended Consumer community, in the context of Federated Archives, that accesses the holdings of several Archives via one or more common Finding Aids.

A characteristic of information that is sufficiently complete to allow it to be interpreted, understood and used by the Designated Community without having to resort to special resources not widely available, including named individuals.

Any type of knowledge that can be exchanged. In an exchange, it is represented by data. An example is a string of bits (the data) accompanied by a description of how to interpret the string of bits as numbers representing temperature observations measured in degrees Celsius (the Representation Information).

A Data Object together with its Representation Information.

A logical container composed of optional Content Information and optional associated Preservation Description Information. Associated with this Information Package is Packaging Information used to delimit and identify the Content Information and Package Description information used to facilitate searches for the Content Information.

That part of the Content Information as described by the Information Property Description. The detailed expression, or value, of that part of the information content is conveyed by the appropriate parts of the Content Data Object and its Representation Information.

The description of the Information Property. It is a description of a part of the information content of a Content Information object that is highlighted for a particular purpose.

The OAIS functional entity that contains the services and functions that accept Submission Information Packages from Producers, prepares Archival Information Packages for storage, and ensures that Archival Information Packages and their supporting Descriptive Information become established within the OAIS.

A type of Access Aid that allows a user to search for and identify Archival Information Packages of interest.

The information which documents the mechanisms that ensure that the Content Information object has not been altered in an undocumented manner. An example is a Cyclical Redundancy Check (CRC) code for a file.

An Information Package, derived from one or more AIPs, and sent by Archives to the Consumer in response to a request to the OAIS.

A request that is generated by a Consumer for information that is to be delivered periodically on the basis of some event or events.

A group of Archives that has agreed to provide access to their holdings via one or more common finding aids.

An object composed of a set of bit sequences.

An identified group of potential Consumers who should be able to understand a particular set of information. The Designated Community may be composed of multiple user communities. A Designated Community is defined by the Archive and this definition may change over time.

The transfer of digital information, while intending to preserve it, within the OAIS. It is distinguished from transfers in general by three attributes: – a focus on the preservation of the full information content that needs preservation; – a perspective that the new archival implementation of the information is a replacement for the old; and – an understanding that full control and responsibility over all aspects of the transfer resides with the OAIS.

The OAIS functional entity that contains the services and functions for populating, maintaining, and accessing a wide variety of information. Some examples of this information are catalogs and inventories on what may be retrieved from Archival Storage, processing algorithms that may be run on retrieved data, Consumer access statistics, Consumer billing, Event Based Orders, security controls, and OAIS schedules, policies, and procedures.

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.

An AIP generated by extracting or aggregating information from one or more source AIPs.

Either a Physical Object or a Digital Object.

A delivery of media or a single telecommunications session that provides Data to an OAIS. The Data Submission Session format/contents is based on a data model negotiated between the OAIS and the Producer in the Submission Agreement. This data model identifies the logical constructs used by the Producer and how they are represented on each media delivery or in the telecommunication session.

The data created and stored in Data Management persistent storage that refer to operation of an Archive. Some examples of this data are accounting data for Consumer billing and authorization, policy data, Event Based Order (subscription) data for repeating requests, preservation process history data, and statistical data for generating reports to Archive management.

A formal repository of terms used to describe data.

A delivery of media or a single telecommunications session that provides Data to a Consumer. The Data Dissemination Session format/contents is based on a data model negotiated between the OAIS and the Consumer in the request agreement. This data model identifies the logical constructs used by the OAIS and how they are represented on each media delivery or in the telecommunication session.

A reinterpretable representation of information in a formalized manner suitable for communication, interpretation, or processing. Examples of data include a sequence of bits, a table of numbers, the characters on a page, the recording of sounds made by a person speaking, or a moon rock specimen.

A set of information that is the original target of preservation or that includes part or all of that information. It is an Information Object composed of its Content Data Object and its Representation Information.

The information that documents the relationships of the Content Information to its environment. This includes why the Content Information was created and how it relates to other Content Information objects.

Those Archives that have Designated Communities with related interests. They may order and ingest data from each other. At a minimum, Co-operating Archives must agree to support at least one common Submission Information Package (SIP) and Dissemination Information Package (DIP) for inter-Archive requests.

The information describing the content of an Information Package from the point of view of a particular Access Aid.

The degree to which a person (or system) regards an object as what it is purported to be. Authenticity is judged on the basis of evidence.

A type of Package Description that is specialized to provide information about an Archival Information Collection for use by Access Aids.

The supporting services such as inter-process communication, name services, temporary storage allocation, exception handling, security, and directory services necessary to support the OAIS.

The role played by those persons, or client systems, who interact with OAIS services to find preserved information of interest and to access that information in detail. This can include other OAISes, as well as internal OAIS persons or systems.

The Data Object, that together with associated Representation Information, comprises the Content Information.

An Archival Information Package where the Archive chooses not to break down the Content Information into other Archival Information Packages. An AIU can consist of multiple digital objects (e.g., multiple files).

The OAIS functional entity that contains the services and functions used for the storage and retrieval of Archival Information Packages.

An organization that intends to preserve information for access and use by a Designated Community.

An Information Package, consisting of the Content Information and the associated Preservation Description Information (PDI), which is preserved within an OAIS.

An Archival Information Package whose Content Information is an aggregation of other Archival Information Packages.

An AIP whose Content Information or Preservation Description Information has undergone a Transformation on a source AIP and is a candidate to replace the source AIP. An AIP version is considered to be the result of a Digital Migration.

An AIP whose Content Information or Preservation Description Information has been upgraded or improved with the intent not to preserve information, but to increase or improve it. An AIP edition is not considered to be the result of a Migration.

A request that is generated by a Consumer for information the OAIS has indicated is currently available.

The OAIS functional entity that contains the services and functions needed to control the operation of the other OAIS functional entities on a dayto-day basis.

A type of software that presents part of or all of the information content of an Information Object in forms understandable to humans or systems.

A software program or document that allows Consumers to locate, analyze, order or retrieve information from an OAIS.

A collection of AIPs that is defined by a Collection Description but for which there is no Packaging Information for the collection in Archival Storage.

The OAIS functional entity that contains the services and functions which make the archival information holdings and related services visible to Consumers.

The information that identifies the access restrictions pertaining to the Content Information, including the legal framework, licensing terms, and access control. It contains the access and distribution conditions stated within the Submission Agreement, related to both preservation (by the OAIS) and final usage (by the Consumer). It also includes the specifications for the application of rights enforcement measures.

Assertions of one or more legal entitlements or permissions pertaining to a Digital Object and/or an Agent.

The File that must be processed first in order to render a Representationcorrectly.

Semantic Unit grouped with one or more other Semantic Units within a Container. A Semantic Component may itself be a Container.

Property of an Entity. Note: The PREMIS DataDictionary makes a distinction between a Semantic Unit and a metadata element. A Semantic Unit isinformation that a Preservation Repository needs to know; a metadata element is how that information isactually recorded. So in practice there could be a one-to-one relationship between a Semantic Unit and its associatedmetadata element; a one-to-many relationship; or even a many-to-one relationship. Ultimately, the translation of a set of Semantic Units into acorresponding set of metadata elements is an implementation issue.

Digital Object consisting of a single File, for example, a technical report complete in one PDFFile.

Write a File to some non-volatile storage devicesuch as disk, tape, or DVD.

Describes theinternal structure of digital resources and the relationships between theirparts. It is used to enable navigation and presentation. (From NINCH Guide to Good Practice http://www.nyu.edu/its/humanities/ninchguide/appendices/metadata.html.)

Relationship between parts of a DigitalObject.

Information describing physical (as opposed to intellectual)attributes or properties of Digital Objects. SomeTechnical Metadata properties are Format specific (thatis, they pertain only to Digital Objects in aparticular Format, for example, color space associatedwith a TIFF image), while others are Format independent(that is, they pertain to all Digital Objectsregardless of Format, for example, size in bytes).

Process performed on a Digital Objectthat results in one or more new Digital Objectsthat are not bit-wise identical to the source Digital Object. Examples of Transformationinclude Migration and Normalization.

Process of comparing a Digital Objectwith a standard or benchmark and noting compliance or exceptions. For example,a File can be validated against aFile format specification or profile; a Representationcan be validated against criteria for completeness.

Property of being readable from media.

Process of scanning a File for maliciousprograms designed to corrupt Digital Objects andsystems.

A type of content found on the World Wide Web, usually in HTML/XHTMLformat (the File extensions are typically .htm or .html) and with hypertextlinks to enable navigation from one page or section to another. Web Pages oftenuse associated graphics Files to provide illustration, and these too can beclickable links. (From Wikipedia http://en.wikipedia.org/wiki/Web_page)

A collection of interlinked Web Pages held inthe same location on the Internet, that is, HTML/XHTML documents accessible viaHTTP on the internet; the set of all publicly accessible Web Sites in existencecomprise the World Wide Web. The pages of a Web Site will beaccessed from a common root URL, the home page, and usually reside onthe same physical server. The URLs of the pages organize them into a hierarchy,although the hyperlinks between them control how the reader perceives theoverall structure and how the traffic flows between the different parts of theWeb Site. (From Wikipedia http://en.wikipedia.org/wiki/Web_page).

Aggregazione indica l'incorporamento di oggetti in un oggetto più grande (piuttosto che una raccolta di oggetti discreti). La proprietà di essere un aggregato può essere dedotta dalla presenza di più file e / o bitstream, che possono essere dedotti dalla presenza di una relazione strutturale intera / parte tra oggetti appartenenti alla stessa categoria. Quella unità semantica non fa distinzione tra un'aggregazione che è ingerita e un'aggregazione creata dal repository di conservazione per l'archiviazione o per altri scopi; tuttavia, questa distinzione non è stata ritenuta essenziale.

Aggregation means the embedding of objects into a larger object (rather than a collection of discrete objects). The property of being an aggregate can be inferred from the presence of multiple files and/or bitstreams, which can be inferred by the presence of whole/part structural relationship between objects belonging to the same category. That semantic unit makes no distinction between an aggregation that is ingested and an aggregation that is created by the preservation repository for storage or other purposes; however, this distinction was not felt to be core.

A Metadata Framework to Support the Preservation of Digital Objects1 defines “quirks” as “any loss in functionality or change in the look and feel of the Content Data Object resulting from the preservation processes and procedures implemented by the archive.” “Anomalies” describe aspects of an object that do not meet the specification for the object. Quirks and anomalies could be held as either the outcomes of Events or classified as properties of Objects. The argument for treating these as outcomes of events is that quirks by definition result from an event, and anomalies are discovered through the event of validation. If treated this way, an anomaly would be recorded as part of the description of a validation event; the semantic unit eventOutcome would indicate problems, and the semantic unit eventOutcomeDetail would record the known anomalies. An argument for treating quirks and anomalies as properties of an object is that this appears to elevate them in importance and gives them a direct as opposed to indirect association with the object. The decision is arbitrary. The Data Dictionary generally treats quirks and anomalies as outcomes of events, recorded in eventOutcomeDetail. However, some specific “anomalies” can also be recorded in other PREMIS entities if this is more appropriate (e.g., deviations from format specifications can be recorded in the formatNote semantic unit as discussed above).

A Metadata Framework to Support the Preservation of Digital Objects1 defines “quirks” as “any loss in functionality or change in the look and feel of the Content Data Object resulting from the preservation processes and procedures implemented by the archive.” “Anomalies” describe aspects of an object that do not meet the specification for the object. Quirks and anomalies could be held as either the outcomes of Events or classified as properties of Objects. The argument for treating these as outcomes of events is that quirks by definition result from an event, and anomalies are discovered through the event of validation. If treated this way, an anomaly would be recorded as part of the description of a validation event; the semantic unit eventOutcome would indicate problems, and the semantic unit eventOutcomeDetail would record the known anomalies. An argument for treating quirks and anomalies as properties of an object is that this appears to elevate them in importance and gives them a direct as opposed to indirect association with the object. The decision is arbitrary. The Data Dictionary generally treats quirks and anomalies as outcomes of events, recorded in eventOutcomeDetail. However, some specific “anomalies” can also be recorded in other PREMIS entities if this is more appropriate (e.g., deviations from format specifications can be recorded in the formatNote semantic unit as discussed above).

L'ordine dei byte determina se i numeri di più di otto bit sono memorizzati dal più al meno significativo ("big-endian") o dal meno significativo al più significativo ("little-endian"). L'ordine dei byte dipende dall'hardware e può causare problemi quando i dati vengono condivisi tra diversi tipi di computer. Tuttavia, non si riferisce a tutti i formati. Ad esempio, è irrilevante per le codifiche come ASCII, in cui un byte equivale a un carattere e UTF-8, che è indipendente dall'ordine dei byte. Pertanto, l'ordine dei byte potrebbe essere meglio trattato come metadati tecnici specifici del formato. Si noti che ANSI / NISO Z39.87 (Dizionario dati - Metadati tecnici per immagini fisse digitali) include l'ordine dei byte come metadati tecnici per le immagini.

Byte order determines whether numbers of more than eight bits are stored from most to least significant (“big-endian”) or from least to most significant (“little-endian”). Byte order is hardware dependent and can cause problems when data is shared between different types of computers. However, it does not pertain to all formats. For example, it is irrelevant for encodings such as ASCII, where one byte equals one character, and UTF-8, which is byte-order independent. Thus, byte order might better be treated as format-specific technical metadata. It is noted that ANSI/NISO Z39.87 (Data Dictionary – Technical Metadata for Digital Still Images) includes byte order as technical metadata for images.

Questo elemento di metadati è importante, ma si tratta di metadati tecnici specifici del formato, utili solo per file di testo e file che possono includere testo.

This item of metadata is important, but it is format-specific technical metadata, useful only for text files and files that can include text.

PREMIS si basa sulla premessa che il "formato di conservazione" è l'oggetto dell'attività di conservazione, che può o meno essere lo stesso del formato di divulgazione. Indipendentemente dal fatto che il formato di conservazione sia immediatamente riproducibile o trasformato per la disseminazione è una scelta di implementazione. Ad esempio, se il formato di conservazione è un'immagine TIFF, un repository di conservazione potrebbe creare una versione di disseminazione (ad esempio un'immagine JPEG) al volo per l'accesso dell'utente, mentre un altro repository potrebbe fornire il master TIFF. Un terzo repository potrebbe memorizzare ed elaborare sia il master TIFF che la copia di accesso JPEG. Il dizionario dei dati non affronta la creazione di oggetti di metadati che non sono memorizzati in un repository di conservazione. Ciò si basa sul presupposto che mentre un formato di divulgazione è importante per un repository operativamente, non è fondamentale per i processi di conservazione.

PREMIS is based on the premise that the “preservation format” is the object of preservation activity, which may or may not be the same as the dissemination format. Whether or not the preservation format is immediately renderable or is transformed for dissemination is an implementation choice. For example, if the preservation format is a TIFF image, one preservation repository might create a dissemination version (say a JPEG image) on the fly for user access, while another repository might deliver the TIFF master. A third repository might store and process both the TIFF master and the JPEG access copy. The Data Dictionary does not address the creation of metadata objects that are not stored in a preservation repository. This is based on the assumption that while a dissemination format is important to a repository operationally, it is not core to preservation processes.

Alcuni formati consentono agli oggetti file di contenere metadati incorporati. Il dizionario dei dati non contiene alcun mezzo per indicarlo al momento, con la consapevolezza che questo probabilmente dovrà essere rivisitato nei prossimi anni poiché sempre più formati includono metadati incorporati. Per il momento, se i metadati incorporati vengono estratti e archiviati altrove, non è necessario notare l'esistenza di metadati incorporati nel file. È anche riconosciuto che esiste una distinzione tra metadati incorporati standard definiti da un formato file e metadati definiti localmente che potrebbero essere inseriti nell'intestazione di un file. Eventuali divergenze locali da formati standard dovranno probabilmente essere documentate come anomalie.

Some formats allow file objects to contain embedded metadata. The Data Dictionary does not contain any means of indicating this for now, with the understanding that this will probably have to be revisited in the next several years as more and more formats include embedded metadata. For the time being, if embedded metadata is extracted and stored elsewhere, there is no need to note the existence of embedded metadata in the file. It is also recognized that there is a distinction between standard embedded metadata defined by a file format and locally defined metadata that might be inserted into a file header. Any local divergences from standard formats will likely need to be documented as anomalies.

L'eventType dell'unità semantica è fondamentale, ma non tutti i tipi di eventi sono stati considerati core e alcuni sono stati omessi deliberatamente dall'elenco di valori suggeriti forniti nel dizionario dei dati. In particolare, la microfilmatura (riformattazione della conservazione), lo spostamento di un file offline e il rinfresco dei media non sono eventi chiave. Gli eventi che potrebbero essere gestiti da un sistema di archiviazione, come il mirroring o la creazione di copie di backup, verrebbero probabilmente registrati in un registro di sistema e non aumentati al livello di un evento con i metadati associati.

The semantic unit eventType is core, but not all types of events were considered core, and some were deliberately omitted from the list of suggested values provided in the Data Dictionary. In particular, microfilming (preservation reformatting), moving a file offline, and media refreshment are not core events. Events likely to be handled by a storage system, such as mirroring or the creation of backup copies, would probably be recorded in a system log and are not raised to the level of an event that has metadata associated with it.

Molte azioni eseguite da un repository di conservazione vengono eseguite periodicamente, ad esempio azioni di monitoraggio giornaliere o settimanali. Potrebbe essere utile registrare una data dell'azione o un "tickler" per la successiva occorrenza pianificata di un evento. Questo è considerato una questione di politica e implementazione del repository e non una proprietà principale degli eventi.

Many actions taken by a preservation repository are performed periodically, for example, daily or weekly monitoring actions. It could be useful to record an action date or “tickler” for the next scheduled occurrence of an event. This is considered a matter of repository policy and implementation, and not a core property of events.

Questo elemento è stato visto come specifico dell'implementazione e dipendente dal sistema. Non è stato visto come informazione che sarebbe stata registrata esplicitamente in un repository. Spesso il percorso o la posizione di un oggetto non sono noti in un sistema di gestione dei contenuti; solo l'identificatore univoco dell'oggetto della risorsa è noto e necessario per il recupero. In alternativa, in alcuni sistemi, come il sistema Handle, solo objectIdentifier è sufficiente per il recupero del file. Pertanto, è stata definita un'unità semantica più ampia e meno dipendente dal sistema: contentLocation. Può essere interpretato in modo restrittivo (un valore potrebbe essere un percorso esatto o un percorso o un nome file "completo") o in generale (qualsiasi informazione necessaria per recuperare un file da un sistema di archiviazione, che può includere informazioni utilizzate da un sistema di risoluzione come Sistema di impugnatura).

This element was seen as both implementation specific and system dependent. It was not seen as information that would be explicitly recorded in a repository. Often the pathname or location of an object is not known in a content management system; only the unique object identifier of the asset is known and needed for retrieval. Alternatively, in some systems, such as the Handle system, the objectIdentifier alone is sufficient for retrieving the file. Therefore, a broader, less system-dependent semantic unit was defined: contentLocation. It can be interpreted narrowly (a value could be an exact path or a “fully qualified” path or filename) or broadly (any information needed to retrieve a File from a storage system, which may include information used by a resolution system such as the Handle system).

PREMIS non considera significativa la distinzione tra un identificatore esterno noto e un identificatore internamente conosciuto. Un identificatore interno potrebbe facilmente diventare noto al di fuori del repository e quindi sarebbe un identificatore globale. Ciò solleva la questione se gli identificatori interni sarebbero sufficientemente unici in un contesto esterno per funzionare come un identificatore globale. Tuttavia, poiché objectIdentifier include sempre un tipo di identificatore e anche un valore, la combinazione di tipo e valore sarebbe univoca anche se il tipo fosse uno schema di repository locale.

PREMIS does not consider the distinction between an externally known identifier and an internally known identifier to be significant. An internal identifier could easily become known outside of the repository and then would be a global identifier. This raises the issue of whether internal identifiers would be sufficiently unique in an external context to function as a global identifier. However, as the objectIdentifier always includes an identifier type as well as value, the combination of type and value would be unique even if the type were some local repository scheme.

Il tipo di supporto Internet e il sottotipo (comunemente chiamato "tipo MIME") sono riassunti in formatDesignation. La designazione del formato è più granulare e precisa del tipo MIME e include schemi di identificazione in più formati, di cui il tipo MIME può essere uno. Un tipo MIME da solo non è abbastanza rigoroso per identificare i formati per la conservazione digitale: non tutti i formati hanno tipi MIME, è un meccanismo di digitazione troppo grossolano, non è necessariamente attuale e non fornisce informazioni sulla versione. È buona norma includere il nome e la versione del formato e utilizzare il tipo MIME solo se non sono disponibili altri dati.

The Internet Media Type and SubType (commonly called “MIME type”) is subsumed under formatDesignation. Format designation is intended to be more granular and precise than MIME type and includes multiple format identification schemes, of which MIME type can be one. A MIME type alone is not rigorous enough to identify formats for digital preservation: not all formats have MIME types, it is too coarse a typing mechanism, it is not necessarily current, and it provides no versioning information. Good practice is to include format name and version and use MIME type only if no other data is available.

Il modello di dati PREMIS asserisce che i metadati descrivono solo un oggetto Representation, File o Bitstream in un dato momento. Se un tale oggetto viene modificato o modificato, viene creato un nuovo oggetto correlato al precedente. Ogni nuovo oggetto ha quindi il proprio set di metadati e viene descritta anche la relazione tra i due. Il modello non consente di modificare un oggetto rappresentazione, file o bitstream e di mantenere una serie di metadati che descrivono una cronologia delle modifiche su quell'oggetto. Pertanto, non ci sarebbe alcuna data di modifica di una rappresentazione, di un file o di un oggetto bitstream, solo una data di creazione per il nuovo oggetto. L'atto di modifica (ad es. Migrazione, normalizzazione) è documentato come un evento ed è collegato all'oggetto creato come risultato di questi processi. In PREMIS, la data di modifica viene considerata nel contesto di un record di evento associato a un oggetto, anziché una data associata a una cronologia delle modifiche ai metadati associati a un oggetto. Vale la pena notare che la maggior parte dei sistemi operativi avrà un modo diverso di registrare queste informazioni e utilizzerà il termine "ultima data di modifica" per la data (e l'ora) in cui è stato creato il file corrente. Alcuni sistemi operativi registrano anche una "data di creazione" che registra la prima data (e ora) che esisteva un file con quel nome anche se si tratta di un oggetto diverso (anche se spesso l'oggetto corrente era basato su quando è stato creato).

The PREMIS data model asserts that metadata describes only one Representation, File or Bitstream object at any given time. If such an object is changed or modified, a new object is created that is related to the previous one. Each new object then has its own set of metadata, and the relationship between the two is also described. The model does not allow for modifying a representation, file or bitstream object and keeping a set of metadata that describes a history of changes about that object. Therefore, there would be no modification date of a representation, file or bitstream object, only a creation date for the new object. The act of modification (e.g., migration, normalization) is documented as an event and is linked to the object that is created as a result of these processes. In PREMIS, modification date is considered in the context of an event record that is associated with an Object, rather than a date associated with a history of changes to the metadata associated with an Object. It is worth noting that most operating systems will have a different way of recording this information, and will use the term “last modified date” for the date (and time) that the current file was created. Some operating systems also record a “creation date” which records the first date (and time) that a file of that name existed even though this is a different object (albeit often one that the current object was based off when it was created).

Non esiste un'unità semantica per un genere o un tipo di supporto che classifichi gli oggetti su un livello molto più alto del formato (ad es. Immagini o video). Lo schema METS consente tale espressività con la presenza di un attributo USE che può essere applicato a file e gruppi di file, ma attualmente non esiste un vocabolario controllato definito per i suoi valori. Si tratta di informazioni potenzialmente utili da conoscere a livello di sistema (ad esempio, per l'esecuzione di azioni di conservazione su un'intera classe di materiali) e, eventualmente, per la categorizzazione di oggetti in termini di modalità di rendering in determinati ambienti. Tuttavia, la digitazione di oggetti di alto livello è probabilmente più utile per lo scambio e l'accesso agli oggetti rispetto ai fini di conservazione. Lo sviluppo di un elenco universalmente accettabile di tipi di oggetto va oltre lo scopo di PREMIS e, senza un elenco di tipi di autorità, questo elemento non sarebbe del tutto utile al di fuori del repository. Questo elemento potrebbe essere registrato in metadati descrittivi.

There is no semantic unit for a genre or media type that would classify objects on a much higher level than format (e.g., images or videos). The METS schema allows such expressivity with the presence of a USE attribute that can be applied to files and file groups, but currently there is no controlled vocabulary defined for its values. This is potentially useful information to know at the system level (for example, for performing preservation actions on an entire class of materials) and possibly for categorizing objects in terms of how they are rendered in certain environments. However, high-level object typing is probably more useful for exchange and access to objects than for preservation purposes. Developing a universally acceptable list of object types is beyond the scope of PREMIS and, without an authority list of types, this element would not be entirely useful outside of the repository. This element might be recorded in descriptive metadata.

Le valutazioni della Permanenza della National Library of Medicine sembrano essere meno una proprietà di un'entità Object che una proprietà di un'entità che definisce le regole aziendali. Le regole aziendali non rientrano nell'ambito di PREMIS.

The National Library of Medicine’s Permanence ratings appear to be less a property of an Object entity than a property of an entity defining business rules. Business rules are out of scope of PREMIS.

Un "profilo" può essere visto come sottotipo o perfezionamento di un formato; ad esempio, la specifica GeoTIFF può essere vista come un profilo di TIFF. C'era una questione se la conformità del profilo dovesse essere vista come qualcosa di separato dalla convalida del formato. L'elemento formato PREMIS è ripetibile, il che significa che è possibile registrare sia la conformità del formato sia una conformità del profilo più specifica. Tuttavia, si raccomanda di registrare solo un singolo formato al livello più specifico (ad esempio, nell'esempio può essere registrata conformità a GeoTIFF che implica conformità a TIFF).

A “profile” can be seen as a subtype or refinement of a format; for example, the GeoTIFF specification can be seen as a profile of TIFF. There was a question of whether profile conformance should be seen as something separate from format validation. The PREMIS format element is repeatable which means that both format conformance and a more specific profile conformance can be recorded. However, it is recommended to record only a single format at the most specific level (e.g., in the example conformance to GeoTIFF could be recorded which implies conformance to TIFF).

Si tratta di metadati realmente descrittivi e quindi fuori dalla portata di PREMIS. Inoltre, PREMIS non considera gli eventi oi processi che si verificano prima di ingerire le conoscenze di base per un repository di conservazione. Alcuni dei contesti che circondano la creazione dell'oggetto possono essere documentati in relazione all'entità Oggetto nella creazione dell'applicazione e il motivo della creazione potrebbe essere registrato come parte dell'eventoDetail per l'evento di creazione.

This is really descriptive metadata and thus out of the scope of PREMIS. Also, PREMIS does not consider events or processes that occur before ingest to be core knowledge for a preservation repository. Some of the context surrounding object creation may be documented in relation to the Object entity in creatingApplication and the reason for creation could be recorded as part of the eventDetail for the Event of creation.

Le relazioni tra fratelli e sorelle hanno sempre una relazione strutturale (e potrebbero anche avere una relazione di derivazione) e dovrebbero quindi rientrare in queste categorie di relazioni piuttosto che essere una categoria separata di relazioni. Ciò che li rende potenzialmente confusi è che il genitore non è sempre memorizzato all'interno del sistema di repository. Ad esempio, un report creato utilizzando Microsoft Word potrebbe essere elaborato per creare una versione PDF per la stampa e una versione HTML per la visualizzazione online. Se entrambe queste rappresentazioni sono state memorizzate nell'archivio di conservazione senza il file Word originale, potrebbe non essere ovvio che le due rappresentazioni abbiano una relazione tra fratelli.

Sibling relationships always have a structural relationship (and may possibly also have a derivation relationship), and should therefore fall under these relationship categories rather than being a separate category of relationship. What renders them potentially confusing is that the parent is not always stored within the repository system. For example, a report created using Microsoft Word might be processed to create a PDF version for printing and an HTML version for online display. If both of these representations were stored in the preservation archive without the original Word file, it might not be obvious that the two representations have a sibling relationship.

Hardware, software e altri oggetti richiesti per permettere la fruizione dei contenuti di un oggetto.

The hardware, software and other objects required to render an Object.

La qualità di essere memorizzato in una forma controllata tale che possa essere azionato da un programma di computer.

The quality of being recorded in a controlled form that can be acted upon by computer program.

Un tipo speciale di unità contenitore del Dizionario dei Dati PREMIS che non ha sottounità definite, ma che viene definita come segnaposto per i metadati non-PREMIS.

A special type of PREMIS container unit that has no subunits defined under it but is designed as a placeholder for non-PREMIS metadata.

Una strategia di conservazione che comporta la riproduzione di un vecchio ambiente tecnologico di fruizione su hardware e/o software di nuova generazione.

A preservation strategy that involves reproducing an old rendering environment on newer hardware and/or software.

Una persona, una organizzazione o un programma per computer che ha un ruolo in un evento o in una dichiarazione sui diritti.

A person, organization or computer program that has a role pertaining to an Event or a statement of Rights.

Un’entità PREMIS che aggrega informazioni sui diritti e sui permessi che riguardano gli oggetti del deposito di conservazione.

A PREMIS Entity that aggregates information about rights and permissions pertaining to Objects in a preservation repository.

Una entità PREMIS che aggrega informazioni sulle azioni che hanno una qualche influenza sugli Oggetti di un deposito.

A PREMIS Entity that aggregates information about actions that affect Objects in the repository.

Un insieme di contenuto che viene considerato come un’unità per gli obiettivi di gestione e descrizione; simile a una “entità bibliografica” nella scienza biblioteconomica.

A set of content that is treated as a unit for purposes of management and description; similar to a "bibliographic entity" in library science.

Caratteristica di un oggetto digitale che ne restringe l’accesso, l’uso o la migrazione.

Features of a digital object intended to restrict access, use or migration.

I metadati che supportano le attività che assicurano l’usabilità nel lungo periodo di una risorsa digitale.

Metadata that support activities intended to ensure the long-term usability of a digital resource.

Una strategia di conservazione che comporta la creazione di una versione diversa di un file digitale in un nuovo formato.

A preservation strategy that involves making a version of a digital file in a newer file format.

Oggetti digitali che sono realmente archiviati e gestiti in un deposito di conservazione. PREMIS difinisce quattro tipi di Oggetti: File, Bitstream, Rappresentazioni e Entità Intellettuali.

Digital items that are actually stored and managed in a preservation repository. PREMIS defines four types of Objects: Files, Bitstreams, Representations and Intellectual Entities.

Un Oggetto che fa parte della stratificazione di software, hardware ed altre dipendenze necessarie ad interpretare correttamente le Rappresentazioni, i File e i Bitstream.

An Object that is part of the technical stack of software, hardware and other dependencies needed to correctly interpret the Representations, Files and Bitstreams.

Un tipo di oggetto PREMIS; i dati all’interno di un file che hanno proprietà comuni ai fini della conservazione e non possono stare da soli.

A type of PREMIS Object; data within a file that have common properties for preservation purposes and cannot stand alone.

Un tipo di oggetto PREMIS; un file di computer, come un PDF o un JPEG.

A type of PREMIS Object; a computer file, like a PDF or JPEG.

Un tipo di oggetto PREMIS; l’insieme di tutti gli oggetti file necessari alla fruizione di un’entità intellettuale.

A type of PREMIS Object; the set of all File Objects needed to render an Intellectual Entity.

Caratteristiche di un oggetto che dovrebbero essere mantenute dalle azioni di conservazione.

Characteristics of an Object that should be maintained through preservation actions.

Documentazione della catena di custodia e dei cambi evolutivi di una risorsa digitale.

Documentation of the chain of custody and change history of a digital resource.

Le tecniche impiegate per assicurare che le risorse digitali rimangano usabili nel lungo periodo; due strategie comuni sono la migrazione e l’emulazione.

Techniques employed to ensure that digital resources remain usable over the long term; two common strategies are migration and emulation.

Unità semantiche che non hanno valore per se stesse ma esistono per raggruppare le sottounità correlate.

Semantic units which take no value of their own but exist to group related subunits.

Pezzi di informazione o di conoscenza.

Pieces of information or knowledge.