Preservation Watch is a well-accepted concept now, first created during the European FP7 project PLANETS in a working group consisting of me and Paul Wheatley. As part of the Planets Functional Model it combines and extents the monitoring activities as mentioned in OAIS. As such it is a valuable contribution to a better description of the Preservation Planning Functional Entity and worthwhile considering to add this concept of Preservation Watch to the OAIS standard.
The Planets Functional Model identifies 3 key preservation functions: Preservation Watch, Preservation Planning and Preservation Action. A detailed description can be found here, this blog focuses on Preservation Watch. Preservation Watch monitors a variety of internal and external entities, including the content preserved in the digital repository itself (via ADMINISTRATION). Where potential changes in the entities are identified (e.g. a new tool is available, a platform is no longer supported, or a new use case becomes popular), the resulting preservation risk is assessed. Critical or imminent risks are passed to Preservation Planning for further analysis and planning of subsequent action. Information gathered from the entities and analysed in the Testbed is used to provide Representation Information Updates to the KNOWLEDGE BASE . For example, the addition of a KNOWLEDGE BASE entry describing a new tool and its capabilities. Preservation Planning assesses Constraints and Risks received from Preservation Watch. Preservation Action performs actions on Content to ensure its continued accessibility and sends appropriate feedback to Preservation Watch.
The Preservation Watch has 4 subfunctions:
Monitor provides the role of collating preservation related information from a variety of internal and external entities. Monitoring can be scheduled on a regular basis but might also be triggered by alerts from Technology Watch services or other sources.. Although the OAIS model contains monitoring functions in the Preservation Planning Function, this is restricted to “Monitoring Designated Community” and “Monitor Technology”. Based on our findings in the Planets project, we concluded that there is more to monitor and that the best way to show this, was to adapt the Preservation Planning Function and add a central role for Preservation Watch. In this new Functional Model we grouped together various aspects that needed to be monitored and as such are part of the Preservation Watch Function.
Risk Analysis provides an assessment of this information, relaying critical risks to Preservation Planning. For example a particular tool becomes obsolete, leaving content in the digital repository without a rendering mechanism. A further Preservation Planning exercise would then be triggered, to consider remaining alternatives.
Representation Information Update provides updates to Representation Information in the KNOWLEDGE BASE, enriching information describing file formats, tools or environments as well as recording Risks and Executed Preservation Plans.
The Testbed provides a controlled environment for studying the operation of tools and services on content in controlled experiments, thereby facilitating the assessment of the capability of the tools and services for preservation purposes. Results are stored in the KNOWLEDGE BASE and these will inform the Preservation Planning activities.
More detailed information about the Preservation Watch Function in relation to Preservation Planning can be found in the final deliverable of the Planets project on http://www.planets-project.eu/docs/reports/Planets_PP7-D6_EvaluationOfPPWithinOAIS.pdf
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