Trustworthy Preservation
Planning with Plato
Andreas Rauber
Department of Software Technology andInteractive Systems
Vienna University of Technology
rauber@ifs.tuwien.ac.at
http://www.ifs.tuwien.ac.at/~andi.................................................

OutlineIntroduction
Why do we need preservation planning?
Preservation planning and Plato
Bringing it all together and closing.................................................

Why do we need Digital Preservation?

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Why do we need Digital Preservation?

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Why do we need Digital Preservation?
 Digital Objects require specific environment to beaccessible :- Files need specific programs- Programs need specific operating systems (-versions)- Operating systems need specific hardware components

 SW/HW environment is not stable:-Files cannot be opened anymore
Embedded objects are no longer accessible/linked
Programs won‘t run
Information in digital form is lost(usually total loss, no degradation)

 Digital Preservation aims at maintaining digital objects
authentically usable and accessible for long time
periods.
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Preservation Planning
Why Preservation Planning?
 Several preservation strategies developed- For each strategy: several tools available- For each tool: several parameter settings available
 How do you know which one is most suitable?
 What are the needs of your users? Now? In the future?
 Which aspects of an object do you want to preserve?
 What are the requirements?
 How to prove in 10, 20, 50, 100 years, that the decision wascorrect / acceptable at the time it was made?
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Preservation Planning Consistent workflow leading to a preservation plan Analyses, which solution to adopt
 Considers- preservation policies- legal obligations- organisational and technical constraints- user requirements and preservation goals Describes the- preservation context- evaluated preservation strategies- resulting decision including the reasoning Repeatable, solid evidence Trust and audit.................................................

Preservation Planning Trust and Audit Compliance to best practices, standards
 3 core initiatives, of which 2 prescriptive- RLG- National Archives and Records Administration Digital
Repository Certification Task Force:
Trustworthy Repositories Audit & Certification: Criteria andChecklist (TRAC)- NESTOR:
Catalogue of Criteria of Trusted Digital Repositories- DCC/DPE:DRAMBORA: Digital Repository Audit Method Based on Risk
Assessment

 Embedding into OAIS model.................................................

Preservation Planning.................................................

OutlineIntroduction
Why do we need preservation planning?
Preservation planning and Plato
Bringing it all together and closing.................................................

Preservation Planning with Plato
Plato
 Preservation Planning Tool Reference implementation of planning workflow
 Web-based application, 1st release 2.0 Nov. 12 2008,
latest version 2.1 released November 2009
 Documents the process and ensures that all steps areconsidered Automation of the planning process via integration ofregistries and services
 Knowledge base to support planning Creates a preservation plan (XML, PDF)
 http://www.ifs.tuwien.ac.at/dp/plato.................................................

Preservation Planning with Plato
Plato
 Assists in analyzing the collection- Profiling, analysis of sample objects via Pronom and other services

 Allows creation of objective tree
- Within application or via import of mindmaps

 Allows the selection of Preservation action tools.................................................

Preservation Planning with PlatoPlato
 Runs experiments and documents results Allows definition of transformation rules, weightings
 Performs evaluation, sensitivity analysis,
 Provides recommendation (ranks solutions).................................................

PP Workflow.................................................

Define Basis Basic preservation plan properties Describe the context-

Institutional settings
Legal obligations
User groups, target community
Organisational constraints

 5 triggers-New Collection Alert (NCA)
Changed Collection Profile Alert (CPA)
Changed Environment Alert (CEA)
Changed Objective Alert (COA)
Periodic Review Alert (PRA).................................................

PP Workflow.................................................

Choose Sample Objects
 Identify consistent (sub-)collections- Homogeneous type of objects (format, use)
- To be handled with a specific (set of) tools Describe the collection- What types of objects?
- How many?
- Which format(s)?

 Selection- Representative for the objects in the collection- Right choice of sample is essential- They should cover all essential features and characteristics ofthe collection in question- As few as possible, as many as needed- Often between 3 – 10.................................................

Choose Sample Objects

 Stratification – all essential groups of digital objects
should be chosen according to their relevance Possible stratification strategies-File type
Size
Content (e.g. document with lots of images, including macros)Time (objects from different periods of times) File Format Identification- DROID- PRONOM.................................................

PP Workflow.................................................

Identify Requirements

 Define all relevant goals and characteristics(high-level, detail) with respect to a given application
domain Put the requirements in relation to each otherÆ Tree structure Top-down or bottom-up- Start from high-level goals and break down to specificcriteria- Collect criteria and organize in tree structure.................................................

Identify Requirements
 Input needed from a wide range of persons,depending on the institutional context and the collection

IT Staff

Domain experts

Administration

Producers

Managers
Lawyers

Curators

OthersTechnical experts.................................................

Consumers

Identify requirements

 Core step in the process Define all relevant goals and characteristics(high-level, detail) with respect to given application domain
 Usually four major groups
 Object characteristics (content, metadata,…) Record characteristics (context, relations,…) Process characteristics (scalability, error-detection,…) Costs (set-up, per object, HW/SW; personnel,…).................................................

Identify requirements

analogue…

… ordigital.................................................

Identify requirements Creation within PLATO with Tree-Editor.................................................

Identify requirements
 Assign measurable unit to each leaf criterion As far as possible automatically measurable
 seconds / Euro per object
 colour depth in bits ...

 Subjective measurement units where necessary diffusion of file format
 amount of expected support
 ...

 No limitations on the type of scale used.................................................

Identify requirements Creation within PLATO with Tree-Editor.................................................

Identify Requirements: Example.................................................

Identify Requirements: Example
Behaviour Visitor counter and similar functionalities can be Frozen at harvesting time Omitted
 Remain operational, i.e. the counter will be increased uponarchival calls(is this desired? count? demonstrate functionality?).................................................

PP Workflow.................................................

Define Alternatives.................................................

PP Workflow.................................................

Develop and Run Experiment Call the migration tools / emulators
 Convert the sample objects / open in emulators
 Take a look at the results.
each of the sample object in various versions
 Measure time / memory needed to migrate/open
 Measure program output, error messages, …

.................................................

PP Workflow.................................................

Evaluate Experiment.................................................

PP Workflow.................................................

Transform measured values

 Measures come in seconds, euro, bits, goodness
values,…
 Need to make them comparable
 Transform measured values to uniform scale Transformation tables for each leaf criterion
 Linear transformation, logarithmic, special scale Scale 1-5 plus "not-acceptable".................................................

PP Workflow.................................................

Set Importance Factors

 Not all leaf criteria are equally important By default, weights are distributed equally Adjust relative importance of all siblings in a branch Weights are propagated down the tree to the leaves.................................................

PP Workflow.................................................

Analyse Results.................................................

Analyse results
Example: Electronic documents
Alternative

Total Score
Weighted Sum

Total Score
Weighted Multiplication

PDF/A (Adobe Acrobat 7 prof.)

4.52

4.31

PDF (unchanged)

4.53

0.00

TIFF (Document Converter 4.1)

4.26

3.93

EPS (Adobe Acrobat 7 prof.)

4.22

3.99

JPEG 2000 (Adobe Acrobat 7 prof.)

4.17

3.77

RTF (Adobe Acrobat 7 prof.)

3.43

0.00

RTF (ConvertDoc 4.1)

3.38

0.00

TXT (Adobe Acrobat 7 prof.)

3.28

0.00

 Deactivation of scripting and security are knock-out criterium (PDF) RTF is weak in Appearance and Structure Plain text doesn’t satisfy several minimum requirements.................................................

PP Workflow.................................................

Outline

IntroductionWhy do we need preservation planning?
Preservation planning and Plato
Bringing it all together and closing.................................................

Digital Preservation
What is a preservation plan?
 10 Sections-Identification
StatusDescription of Institutional Setting
Description of Collection
Requirements for Preservation
Evidence for Preservation Strategy
Cost
Trigger for Re-evaluation
Roles and Responsibilities
Preservation Action Plan

Preservation Plan Template.................................................

Preservation Planning with Plato
What we have now: Basic Preservation Plan:- PDF: Preservation Plan.pdf- XML: Preservation Plan.xml

 That was developed in a solid, repeatable and documented
process That is optimal for the needs of a given institution and for thedata at hand.................................................

Conclusions
 Physical preservation ensures longevity of resources
 Simple risk analysis reporting Preservation Planning to ensure “optimal” preservation
 A simple, methodologically sound model to specify anddocument requirements
 Repeatable and documented evaluation
 Basis for well-informed, accountable decisions
 Follows recommendations of TRAC and nestor
 Plato:- Tool support to perform solid, well-documented analyses- Creates core preservation plan.................................................

Thank you!

http://www.ifs.tuwien.ac.at/dp.................................................