Current Applications of the OAIS Model David Giaretta

Outline Conformance – what does it mean Examples NSSDC CDPP Lotar

Conformance – what does it mean? Section 1.4: A conforming OAIS archive implementation shall: Support the model of information described in section 2.2 But OAIS RM does not define or require any particular method of implementation Fulfill the responsibilities listed in section 3.1 OAIS RM does not specify mechanisms Roadmap identifies areas suitable for OAIS-related standards

Negotiates and accepts Information Packages from information producers Obtains sufficient control to ensure long-term preservation Determines which communities (designated) need to be able to understand the preserved information Ensures the information to be preserved is independently understandable to the Designated Communities Follows documented policies and procedures which ensure the information is preserved against all reasonable contingencies Makes the preserved information available to the Designated Communities in forms understandable to those communities OAIS Responsibilities

NSSDC - DIOnAS Data migration project DIOnAS Using OAIS concepts Producing AIP’s Transforming existing data to Canonical format from VMS operating system specific format Maintaining metadata to specify VMS- specific features

AIP Based on ISO (SFDU packaging) ADID is an internationally object-type- unique identifier Points to additional metadata This metadata may initially be very simple BUT can be enhanced later

SFDU concept

NSSDC - IMAGE satellite data NSSDC provided software to IMAGE project to convert their “Level-0.5” data products into AIPs Original data is tar files containing “Universal Data Format (UDF) files. Consumers will be provided with the UDF files plus software to read these This may change as UDF falls out of use

IMAGE satellite data

Negotiates and accepts Information Packages from information producers Obtains sufficient control to ensure long-term preservation Determines which communities (designated) need to be able to understand the preserved information Ensures the information to be preserved is independently understandable to the Designated Communities Follows documented policies and procedures which ensure the information is preserved against all reasonable contingencies Makes the preserved information available to the Designated Communities in forms understandable to those communities OAIS Responsibilities

CDPP CDPP created in 1998 about 10 missions (WIND, ARCAD, …), 30 experiments, 100 data sets OAIS type Information objects and type of objects Domain dictionary (has already been run in on many missions) Modeling of delivered data Standards and tools (examples) Data description in EAST is required from the producers Tools are provided to create these

CDPP

CDPP data delivery Example of data delivery model Representation Information Data Objects PDI Source Context Reference EAST Structure sheet Catalogs Data Entity Dictionar y DED File Descriptive docs DIF Data files Mission, experiment descriptive files Mission Experiments Data set (main, auxiliary data, images)

EAST The EAST language was designed to meet three objectives in order to enable : a complete description of any given data format, without any 'ephemeral' references to any short-life file management systems, access to the values of the data by means of generic tools which do not require writing of even a single line of specific code for the data to be read, formatting the data on their storage or exchange medium while guaranteeing a structure that matches their description. The EAST language is an international standard (CCSDS and ISO). Tools based on this standard have been developed. They can be used to help players throughout the "data life cycle".

EAST CNES point of view : EAST success will be achieved by using free tools. The user by using the OASIS tool doesn ’t have to learn a new language. package logical_PRODUCT_X_SUN_FCSTC000 is type PRODUCT_X_NAME is (PRODUCT_X) ; for PRODUCT_X_NAME'size use 72 ; type AGENCY_ID is (CNES, NASA, USER_ESA, BNSC, CCSDS) ; for AGENCY_ID'size use 8 ; type NUMBER_TYPE is range ; for NUMBER_TYPE'size use 32 ; type PRODUCT_ID_TYPE is record NAME : PRODUCT_X_NAME ; PRODUCER : AGENCY_ID ; NUMBER : NUMBER_TYPE ; end record ; for PRODUCT_ID_TYPE use record NAME at 0 * WORD_16_BITS range ; PRODUCER at 4 * WORD_16_BITS range ; NUMBER at 5 * WORD_16_BITS range ; end record ; for PRODUCT_ID_TYPE'size use 112 ; Some lines of EAST

Snapshot d ’écran OASIS

Data Entity Dictionary Specification Language Design Goals of DEDSL Able to carry the definitions of data elements for various purposes Establish a discipline/domain dictionary independent of any particular data product usage Establish a product level dictionary that can be specialized from a domain level dictionary or created independently Support registration of dictionaries as whole entities Provides standard attributes for use in the description of scientific data products Attribute set easily extendable by any Data Entity Dictionary creator Support both human understanding and automated validation and processing Harmonized with ISO data element efforts

DEDSL Concepts One Abstract syntax with multiple concrete syntaxes defined for different languages and environments The Abstract Syntax does not specify the schema or physical design of a Data Entity Dictionary implementation The concrete syntax uses the constructs of the underlying language to implement the abstract model Entities are described by the values of a set of standard Attribute values which may be extended by specifying user defined attributes Attributes are defined by a set of Descriptor values A Data Entity Dictionary consists of: 1 set of Dictionary Entity attribute definition 0 or more User-defined attribute definitions 1 or more Data Entity Definitions A Data Entity Dictionary may be transferred using any agreed DEDSL concrete syntax specification.

Dictionary Attributes Provide information that applies to the entire Data Entity Dictionary: IDENTIFYING *Dictionary_name RELATIONAL External_dictionary_reference DEFINITIONAL Dictionary_definition REPRESENTATIONAL *Text_field_character_set Case_sensitivity default=not_case_sensitive *Language ADMINISTRATIVE *DEDSL_version Dictionary_version Dictionary_identifier *= mandatory

HTML pages are inserted into MS WORD documents Input Output of OASIS EAST DATA Syntaxic Description INTERPRETER : Library for reading and validating data DATA GENERATOR : Library for writing data (generation of data for simulation) DED PVL Semantic Description DED XML XML translator XSL Processor DED DTD HTML Users documentation Data Description

Main CDPP difficulties Non-availability of the Producer, or inadequate available resources Diversity of experiments and data produced Late intervention of the Archive in the data production process Absence of standard archiving structuring format (in Plasma Physics) No imposed schedule

Negotiates and accepts Information Packages from information producers Obtains sufficient control to ensure long-term preservation Determines which communities (designated) need to be able to understand the preserved information Ensures the information to be preserved is independently understandable to the Designated Communities Follows documented policies and procedures which ensure the information is preserved against all reasonable contingencies Makes the preserved information available to the Designated Communities in forms understandable to those communities OAIS Responsibilities

LOTAR Long Term Archiving and Retrieval and Product Data within the Aerospace Industry AIRBUS MTU EADS Fairchild Dornier PROSTEP AG ProSTEP iViP Association

Requirements Very large number of 3-D CAD models Various formats – software dependent “quasi-safe for about 10 years” Not safe enough for Legal and product liability Legal: Ability to verify the conformity of a part with its documentation System has to enable the user to assure the provisions of a law regarding data security and protection of data privacy over the life cycle of the archives Possibility to audit the process of archiving and retrieval Security Ensure the information is understandable by the Designated Community without the assistance of the information producers …

Approach Use vendor neutral ISO (STEP) Use OAIS RM Document examines all the functional entities in great detail Recognises that Designated Community may be broadened

Negotiates and accepts Information Packages from information producers Obtains sufficient control to ensure long-term preservation Determines which communities (designated) need to be able to understand the preserved information Ensures the information to be preserved is independently understandable to the Designated Communities Follows documented policies and procedures which ensure the information is preserved against all reasonable contingencies Makes the preserved information available to the Designated Communities in forms understandable to those communities OAIS Responsibilities