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Planning to Maximize Longevity of Digital Information. Howard Besser UCLA School of Education & Information http://www.gseis.ucla.edu/~howard. Planning to Maximize Longevity of Digital Info-. The Ecology Metaphor Why are you Managing this Information? Major Issues Facing Digital Projects
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Planning to Maximize Longevity of Digital Information Howard Besser UCLA School of Education & Information http://www.gseis.ucla.edu/~howard
Planning to Maximize Longevity of Digital Info- • The Ecology Metaphor • Why are you Managing this Information? • Major Issues Facing Digital Projects • The Short Life of Digital Info • Important Planning Considerations • Key Considerations for Imaging Projects
Why are you Managing this Information? • Organizational mission & type • Users • Uses
Major Issues Facing Digital Projects • Dangerous Changes in Intellectual Property Law • Intellectual Access • Storage • Delivery • Integration with other tools • Interoperability
Serious Longevity Problems • What we know from prior widespread digital file formats • Images separating from their metadata • Inaccessibility of software needed to view a work • Inability to even decode the file format of a work
The Short Life of Digital Info: Digital Longevity Problems- • Disappearing Information • The Viewing Problem • The Scrambling Problem • The Inter-relation Problem • The Custodial Problem • The Translation Problem
The Viewing Problem • Digital Info requires a whole infrastructure to view it • Each piece of that infrastructure is changing at an incredibly rapid rate • How can we ever hope to deal with all the permutations and combinations
The Scrambling ProblemDangers from: • Compression to ease storage & delivery • Container Architecture to enhance digital commerce
The Inter-relation Problem • -Info is increasingly inter-related to other info • -How do we make our own Info persist when it points to and integrates with Info owned by others? • -What is the boundary of a set of information (or even of a digital object)?
The Custodial Problem • In the past, much of survival was due to redundancy • How do we decide what to save? • Who should save it? • Mellon-funded E-Journal Archives • How should they save it?-
The Custodial Problem:How to save information? • Methods for later access • Refreshing • Migration • Emulation • Issues of authenticity and evidence
The Translation Problem • Content translated into new delivery devices changes meaning • -A photo vs. a painting • -If Info is produced originally in digital form in one encoded format, will it be the same when translated into another format? • Behaviors
Pieces of the Solution (1/2) • -We need to insist upon clearly readable standardized ways for digital objects to self-identify their formats • -We should discourage scrambling • -We need to better understand information inter-relates to other Info, and what constitutes “boundaries” of Info objects
Pieces of the Solution (2/2) • -People and organizations wishing to make information persist need guidelines of how to go about doing it • -We need to better understand how translating from one storage or display format to another affects the meaning of a work • -We need to save the “behaviors” of a digital object, not just its “contents”
Conceptual Approaches to Digital Preservation • Refreshing always necessary due to volatility of physical strata • Impact on evidential value • Migration -- advantages & disadvantages • Emulation -- advantages & disadvantages
To deal with Immediately- • Persistent IDs • Metadata
Persistent IDs--the Problem • Need to separate work ID from work location • URNs probably won’t be ready until 2003 • Becomes a business process issue when one organization maintains the resource and another organization references it (ie. licensed from vendors or managed by separate administrative structures)
More Persistent IDs--the Approach for today • PURLs • Handles • HTTP redirects • And worry about costs now and conversion costs when URNs become feasible
Data Set ManagementMore issues with referencing IDs • References for mirror sites • References for back-up sites when main site is down or bottle-necked • References for off-site copies and archival copies
Metadata can be the first line of defense • Can tell you • where the file is (if you can’t find the file) • where more info about the file is (if you have the file but most other metadata has become separated) • what the file format is • what the compression scheme is • what application program and version is needed for the file
Structural Metadata Issues • http://sunsite.berkeley.edu/moa2
User User Berkeley Longevity Server Berkeley Delivery Server User User Other Delivery Server Other Delivery Server Other Delivery Server Architecture: Separating Longevity and Delivery Servers
Groups Working onthe Big Problemhttp://sunsite.Berkeley.EDU/Longevity/ • CPA Task Force • Getty “Time & Bits” Conference & Follow-ups- • Emulation experiments in US and Europe • NEDLIB, CURL, Michigan • Mellon-funded E-Journal Archive experiments • Internet Archive • Long Now
Steward Brand Howard Besser Brian Eno Danny Hillis Peter Lyman Brewster Kahle Kevin Kelly Jaron Lanier Doug Carlston John Heilemann Ben Davis Margaret MacLean Bruce Sterling Paul Saffo Time & Bits Participants
Groups Working onPieces of the Big Problemhttp://sunsite.berkeley.edu/Longevity/ • Internet Archive • Long Now • Emulation experiments in US and Europe • NEDLIB, CURL, Michigan
Journal Archiving • License, don’t own; may not be even able to obtain right to make archival copy • Increasingly no paper back-up at all • Usually we don’t have the important redundancy factor • Stanford’s LOCKSS Project (Lots of Copies Keeps Stuff Safe) and its problems (http://lockss.stanford.edu)
Complexity of Rich Media • Works often have artistic nature (including video games) • Enormous number of elements can, at times, be very important to preserve (pacing, original artifact, elements used to construct the artifact) • Too complex to save every one of these aspects for every type of material • Importance of saving documentation
Important Planning Considerations • File Formats • Choosing Interoperable Systems • Adhere to standards • Vendors with large installed base • Refreshing and/or Migration
Key Considerations for Imaging Projects- • Users' Needs • Image Quality • Intellectual Property • Standards • Topology • Tools & Processes
Key Considerations for Imaging Projects (1 of 3) • Users' Needs • Quality of Digital Surrogate • Interoperable desktop applications • Image Quality • Archival • Current online delivery
Key Considerations for Imaging Projects (2 of 3) • Intellectual Property • Standards • Modular and Layered Architecture • Terminology • Technical imaging information • Topology
Key Considerations for Imaging Projects (3 of 3) • Tools & Processes • Scanners • Compression techniques • Linking files • Workflow • Interoperable desktop applications
Think about users (and potential users), uses, and type of material/collection Scan at the highest quality that does not exceed the likely potential users/uses/material Do not let today’s delivery limitations influence your scanning file sizes; understand the difference between digital masters and derivative files used for delivery Many documents which appear to be bitonal actually are better represented with greyscale scans Include color bar and ruler in the scan Use objective measurements to determine scanner settings (do NOT attempt to make the image good on your particular monitor or use image processing to color correct) Don’t use lossy compression Store in a common (standardized) file format Capture as much metadata as is reasonably possiple (including metadata about the scanning process itself) Some nuts-and-boltsPlanning Considerations
One Final Question:Who will collect the digital works of today that should become the Special Collections of tomorrow? • web sites • zines • electronic journals • listserve and email discussions • drafts of works that later become famous
Planning to Maximize Longevity of Digital Information Howard Besser UCLA School of Education & Information http://sunsite.berkeley.edu/Longevity/ http://www.gseis.ucla.edu/~howard http://sunsite.berkeley.edu/moa2 http://lockss.stanford.edu http://www.longnow.com/10klibrary/TimeBitsDisc/ http://www.archive.org/