H ARVARD U NIVERSITY L IBRARY The Global Digital Format Registry (GDFR) Project Stephen Abrams Harvard University Andreas Stanescu OCLC CNI Fall Task Force Meeting Washington, DC, December 10-11, 2007

H ARVARD U NIVERSITY L IBRARY Digital preservation and format Preservation is concerned with ensuring access to managed digital assets over time Thus, preservation activities are focused on –Viability –Fixity –Authenticity –Interpretability –Renderability The last two are primarily a function of format

H ARVARD U NIVERSITY L IBRARY Without format typing, all content is opaque ffd8ffe000104a ffed0fb050686f74 6f73686f e d 03e90a e e666f f40240ffeeffee fc d f d03ed0a f6c f 6e a

H ARVARD U NIVERSITY L IBRARY Without format typing, all content is opaque ffd8ffe000104a ffed0fb050686f74 6f73686f e d 03e90a e e666f f40240ffeeffee fc d f d03ed0a f6c f 6e a SOI APP0 JFIF 1.2 APP13 IPTC APP2 ICC DQT SOF0 183x512 DRI DHT SOS ECS0 RST0 ECS1 RST1 ECS2...

H ARVARD U NIVERSITY L IBRARY Without format typing, all content is opaque ffd8ffe000104a ffed0fb050686f74 6f73686f e d 03e90a e e666f f40240ffeeffee fc d f d03ed0a f6c f 6e a SOI APP0 JFIF 1.2 APP13 IPTC APP2 ICC DQT SOF0 183x512 DRI DHT SOS ECS0 RST0 ECS1 RST1 ECS2...

H ARVARD U NIVERSITY L IBRARY Global Digital Format Registry “The Global Digital Format Registry (GDFR) will provide sustainable services to collect, review, store, discover, and deliver significant representation information about digital formats.” –Centrally-organized collection and review –Distributed storage, discovery, and delivery on a network of independent, but cooperating registries

H ARVARD U NIVERSITY L IBRARY What is a format? “A serialized encoding of an abstract information model” Encompasses the nominal sense of “file format” as well as a range of conceptual entities from the micro to the macro level –IEEE 754 floating point number –File system –In both case, there are well-defined syntactic and semantic rules for mapping from information to bits, and back again

H ARVARD U NIVERSITY L IBRARY What’s wrong with MIME types?

H ARVARD U NIVERSITY L IBRARY What’s wrong with MIME types? Non-standardized documentation Intended for human, not machine consumption Coarse granularity –image/tiff vs.TIFF 4.0 – 6.0 Baseline Class B, G, P, R Extension Class Y TIFF/EP TIFF/IT with f ile types CT, LW, HC, MP, BP, BP, BL, FP Exif 2.0 – 2.2 GeoTIFF TIFF/FX DNG

H ARVARD U NIVERSITY L IBRARY GDFR project Two DLF-sponsored invitational workshops –University of Pennsylvania, January 2003 –Washington, March 2003 Two independent demonstration projects –FRED [John Ockerbloom, University of Pennsylvania] tom.library.upenn.edu/fred/ –FOCUS [Joseph JaJa, University of Maryland]

H ARVARD U NIVERSITY L IBRARY GDFR project Harvard University Library (HUL) funded for 2 years by the Andrew W. Mellon Foundation Staffing and technical work subcontracted by HUL to OCLC (July 2006)

H ARVARD U NIVERSITY L IBRARY GDFR project oversight Technical Working Group (TWG) –Bibliothèque nationale de France –British Library –California Digital Library –Digital Curation Centre, UK –Library of Congress –National Archives, UK –National Archives and Records Administration –National Library of Australia –National Library of New Zealand –Stanford University –University of Pennsylvania

H ARVARD U NIVERSITY L IBRARY General development goals A generalized registry framework, specialized for the distributed GDFR application Based on well-known products and protocols Human and machine interfaces Full information content expressible in XML form, and can be re-instantiated from that expression Platform independence Globally fault tolerant Open source

H ARVARD U NIVERSITY L IBRARY GDFR data model Consistent with PRONOM registry

H ARVARD U NIVERSITY L IBRARY Identifiers Canonical, GDFR-assigned identifier –“info” URI info:rfa/gdfr1/Formats/1 Other well-known identifiers –Common name “TIFF”, “Tagged Image File Format” –MIME type image/tiff –PRONOM identifier info:pronom/fmt/7 –Library of Congress Format Description Document (FDD) identifier fdd000022

H ARVARD U NIVERSITY L IBRARY Classification scheme Eight facets –Genre (required)text, still-image, sound, aggregate, … –Role (required)family, file-format, encoding, serialization –Composition unitary, container-bundle, container-wrapper –Form binary, text –Constraint structured, unstructured –Basis sampled, symbolic –Domain astronomy, cad-cam, gis, web-archive, … –Transform compression, encryption, message-digest, …

H ARVARD U NIVERSITY L IBRARY Classification scheme Examples –TIFF (Tagged Image File Format) genre:still-image role:family composition:container-wrapper form:binary basis:sampled –LZW (Liv-Zempel-Welch) genre:still-image role:encoding transform:compression –SVG (Scalable Vector Graphics) genre:still-image role:file-format form:text basis:symbolic

H ARVARD U NIVERSITY L IBRARY Signatures External signatures –File extension –Mac OS type –Mac OS X Uniform Type Identifiers (UTI) Internal signatures –“Magic numbers” –Required vs. optional –Fixed vs. restricted vs. unrestricted

H ARVARD U NIVERSITY L IBRARY Grammar Formal description of the syntactic grammar underlying a format, expressed in some formal typed notation –BNF Backus-Naur Form –BSDL MPEG-21 Bitstream Syntax Description Language –DFDL Data Format Description Language –EAST CCSDS B-2 –XCEL Extensible Characterisation Extraction Language

H ARVARD U NIVERSITY L IBRARY Assessment Assessment of a format, expressed in some formal typed notation –Cornell Virtual Remote Control (VRC) –DTSC PANIC –Library of Congress Sustainability, Quality, Function (SQF) –National Library of Australia AONS –OCLC INFORM

H ARVARD U NIVERSITY L IBRARY Documentation Specification documents (and software files) can be managed and distributed in the network –Applicable only in cases of public domain resources or if explicit permission is granted by rights holders –Other documents (and software) will be referenced by full citation, including actionable links where possible –Mechanism for individuals or institutions to register locally-held copies, with terms of use

H ARVARD U NIVERSITY L IBRARY Software Format role Input, output Process type Characterize, create, edit, identify, … Enables discovery of transformative processing chains

H ARVARD U NIVERSITY L IBRARY Relationships Modification BWF → WAVE –ExtensionDNG → TIFF 6.0 –Restriction PDF/A → PDF 1.4 Definition NITF → XML DTD Requisite XML → Relax NG Containment ZIP → * Equivalence DXF (ASCII) → DXF (binary) Version Word 97 → Word 6.0 Affinity SPIFF → JPEG

H ARVARD U NIVERSITY L IBRARY GDFR node Based on the OCLC IWSA / RFA framework

H ARVARD U NIVERSITY L IBRARY GDFR node Java, Apache/Tomcat, Berkeley DB XML GNU LGPL license –Including pre-existing OCLC technology and technology newly- developed for the project Release schedule –v0.1 (alpha)March 23, 2007 –v0.1 (beta)June 14, 2007 –v1.0 June 30, 2007 –v1.1 August 12, 2007 –v1.3 September 17, 2007 –v1.3.1 October 26, 2007

H ARVARD U NIVERSITY L IBRARY GDFR node

H ARVARD U NIVERSITY L IBRARY GDFR node

H ARVARD U NIVERSITY L IBRARY GDFR node

H ARVARD U NIVERSITY L IBRARY GDFR network Peer-to-peer network of independent, but cooperating registries communicating over a common protocol

H ARVARD U NIVERSITY L IBRARY GDFR network Public notification of the availability of new data –RSS feed available at well-known public address to which remote nodes can subscribe Remote harvesting of local data –OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting) Initially, a single source (root node) for all new data

H ARVARD U NIVERSITY L IBRARY Project status Extensive internal testing of GDFR software in a stand-alone mode Current project activities are focused on –Implementing the distribution and synchronization functions –Building the network –Data acquisition –Succession planning

H ARVARD U NIVERSITY L IBRARY Initial population Manual addition is possible, but time consuming Automated update using Atom What sources are available for bulk population? –PRONOM registry –Library of Congress Format Description Documents (FDD) –Unix / Linux magic(4) database

H ARVARD U NIVERSITY L IBRARY Subsequent population RFC 2026, Internet Standards Process –“Iterations of review by the... community and revision based upon experience” Draft distribution and public discussion Approval by “area” editors Release to the network for distribution

H ARVARD U NIVERSITY L IBRARY Sustainability The technological solution is the (relatively) easy part, but… –The technology is expendable –The important point is for the data to survive, evolve, and expand

H ARVARD U NIVERSITY L IBRARY Governance and succession Mellon funding was for technical work only At the end of the two year project… –Harvard will continue maintenance for up to two years –Library of Congress has agreed to be a care-taker agency until a permanent body is identified

H ARVARD U NIVERSITY L IBRARY Governance and succession NARA GDFR governance investigation –Part of the Electronic Records Archives (ERA) initiative –GDFR Governance Workshop, November 2007 Bibliothèque et Archives, Canada NARA Corp. for National Research Initiatives NASA Digital Curation Centre, UK NIST Digital Library Federation National Library of Australia General Services Administration National Library of New Zealand Georgia Institute of Technology San Diego Supercomputer Center Government Printing Office Stanford University Harvard University Statens Archiv, Sweden IBM Watson Research Center Tessalla Support Services Koninklijke Bibliotheek, Netherlands University of Pennsylvania Library of Congress MIT

H ARVARD U NIVERSITY L IBRARY Administrative considerations Policy –Who (and how many) can join the network? –What are the eligibility requirements? –What are the rights and obligations of membership? Technical –Who will maintain and enhance the data model? –Who will maintain, enhance, distribute, and support the software?

H ARVARD U NIVERSITY L IBRARY Administrative considerations Data –Who will contribute data? –Who will vouch for data authenticity? –Who will ensure data integrity? Financial –What are the real human and system costs associated with GDFR operation? –Who pays, and how?

H ARVARD U NIVERSITY L IBRARY Summary The GDFR is an enabling technology that will support digital repository and preservation activities –Supports the strong typing of digital assets at an appropriate level of granularity –Enables the future recovery of the syntax and semantics associated with typed digital assets –A means to pool and redistribute the expertise of the international digital preservation community

H ARVARD U NIVERSITY L IBRARY For more information…