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It's difficult to believe that in four short years the Planets project (external link) has accomplished as much as it has, but such is the power and effectiveness of wise collaboration.

PlanetsPlanets – which stands for Preservation and Long-term Access through NETworked Services – began in 2006 when 16 of Europe's major cultural and technological institutions pooled their digital-preservation expertise and resources. Adam Farquhar, head of Digital Library Technology at the British Library, said, "From the beginning of the project, we were driven by the question, 'How do we make sure that we can be good stewards of our digital material?'"

Planets not only had a strong representation of problem owners – the cultural institutions – they also had the best advanced-technology researchers, such as Microsoft and IBM. Farquhar said, "Our partners could not only see the problem and feel it acutely but also see how to provide practical solutions today and identify long-term research problems."

The result of Planets research and development is a comprehensive framework and suite of tools for long-term digital preservation and access. "The key design principle is that we wanted to have a framework that could be extended easily and could take advantage of the best components that were available," Farquhar said. The overall framework addresses what is to be done, planning beginning to end, and the suite of tools addresses how it is to be done.

"Digital information is brittle and short-lived unless we take active steps to preserve it now."
— Open Planets Foundation

The framework allows for the inclusion of other tools in addition to those in the suite. All of the tools are required to be open source and are seamlessly integrated into services in a distributed service network.

One of the main components of Planets is Plato, which enables users to plan their projects by analyzing their collections, characterizing their content and using a test bed to evaluate the appropriateness of various tools and services. Users can test tools again and again to determine which tools best meet their needs.

Farquhar cited a recent Planets case study about testing a format-conversion tool. The British Library had a collection of page images of historic newspapers (external link); the images were in TIFF format, which, even though it is uncompressed, lossless and retains a high quality, presented the British Library with several preservation challenges. Plato tests confirmed that conversion to the JPEG 2000 format would retain quality and require much less storage space. A subsequent mass conversion of the TIFF files to JPEG 2000 confirmed what Plato predicted. "Once we made the transition to JPEG 2000, we were able to save 25 – 30 percent on storage costs," said Farquhar.

Adam Farquhar

Adam Farquhar

After users run their experiments they can document the results. These documents record the planning and decision process and become part of the Plato environment. Farquhar said, "After you've drawn your conclusions, with the push of a button you can publish them in a structured document recording all the considerations you made, the tests you conducted and the conclusions you drew." This project documentation becomes part of a library in which all users can research the history of other tests.

Another Planets feature is software emulation, which enables access to older content. The emulation service includes the tools Dioscuri (external link) (an x86 emulator written in JAVA), GRATE (remote emulation solution) and the Universal Virtual Computer (external link). Emulation is mostly used to revive older games but can also be used to re-create the look and feel of an older application.

Emulation is not always the solution to reproducing the original experience. Users can either preserve the original hardware and software (by, say, holding onto a 1989 PC or Mac with its original operating system) or emulate the look and feel of the original program. The second choice is an expensive but possibly more practical option.

Planets has also developed the Preservation Watch Service to monitor the digital world for changes in software and hardware. Users can learn when a new tool or technique is available; be alerted when a new compression algorithm could help reduce storage costs; find about new security threats to their systems; or learn about changes in software, operating systems or hardware that might make it harder to access their content. Farquhar said, "Sometimes, that's as simple as knowing that Sony stops the production of floppy disks, and likewise, that hardware vendors no longer include floppy disk drives in their machines." This is still a work in progress as Planets developers look into automating this kind of information, for example, by monitoring "hits" in search engines.

So, what lies ahead? The official Planets project ended on May 31, 2010, but their activities continue on with the Open Planets Foundation (external link), a non-profit membership-supported organization founded in the UK. Picking up where the project left off, the aim of the Foundation is to expand activities and user communities for digital preservation beyond Europe. Farquhar said that their goal is to provide professional support well beyond what was produced in the Planets project.

Farquhar also emphasized the overall need for collaboration in digital preservation because all larger institutions can learn from their similar experiences. There will be a new round of funded projects coming out of the European Commission soon and more opportunities for such collaboration.

The Planets resources are freely available. The suite of software tools used by the Planets project is described on the Planets site (external link) and the source code is available on Source Forge (external link).

On a material side note, the Planets project is conducting a traditional time-based experiment with the Planets Time Capsule (external link), using five digital objects: a JPEG photograph, a message in Java source code, a short film in .MOV format, a web-page in HTML and a brochure in PDF. It also includes much of the information required to understand the objects, including the file format specifications and encodings. They are stored in old and new formats on a variety of media and the purpose of the experiment is to see how long these digital objects and formats might last. "We put all this stuff in a metal box and stuck it under a mountain in the Swiss Alps," Farquhar said. "The plan is to retrieve this capsule in 10 or 20 years to see what can still be accessible." There are also plans to use the time capsule contents for educational purposes.

And finally, for a different yet entertaining view of Planets, watch DigiMan vs. Team Chaos in the video "Team Digital Preservation and the Planets Testbed (external link)," the latest in the video series produced by Digital Preservation Europe.

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