Building an Electronic Records Archive at the National Archives and Records Administration Recommendations for a Long-Term Strategy (2005) / Chapter Skim
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1 Ongoing Technology Change and Rising User Expectations
1 Ongoing Technology Change and Rising User Expectations
Pages 18-34
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From page 18... ...
Although it is difficult to isolate the amount of federal government information in these general data, there is no reason to assume that the federal government is not experiencing these broader trends. A growing percentage of information is born digital, stored in file servers, database systems, correspondence-management systems, and other electronic information systems, and not systematically retained on paper.
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From page 19... ...
Five major technology trends support a prediction that the National Archives and Records Administration (NARA) will soon face an avalanche of digital materials: · Computer technology makes it easier and less expensive to record more information than can be recorded in the paper world.
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From page 20... ...
Finally, the total number and variety of record data types that must be stored by the National Archives and Records Administration and other repositories will increase over time as new versions of existing data types and entirely new data types are invented.4 The overall growth in the variety of data types will be accompanied by spurts of growth and contraction in the number of data types in active use at any point in time: as a new class of record types emerges, one will likely see an initial explosion of data types. That proliferation will occur as various vendors introduce products, and it will be followed by a consolidation to a smaller number of de facto standards as the market picks winners and losers.
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From page 21... ...
PLANNING FOR CONTINUED TECHNOLOGY CHANGE It is envisioned that NARA's Electronic Records Archives (ERA) will operate for many decades.
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From page 22... ...
And there is no reason to suppose that these sorts of sustained performance improvements will not continue into the indefinite future. Exploiting the Commercial Mainstream The ERA system will benefit from continuing technology evolution only if the ERA implementation stays roughly in step with mainstream commercial trends.
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From page 23... ...
Today's trend in moving to disk from tape for mass storage is an example of what often happens in such cases, with a very high volume product replacing a relatively low volume product. Despite the anticipated rapid changes in many component technologies, past experience suggests that network interoperability will be relatively stable.
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From page 24... ...
The transformation of an uncompressed bitmap image into a run-length encoding produces a file equivalent to the original bit stream, assuming, of course, that the technical metadata identify or define the new representation correctly. The lowest level of a system architecture for a digital archive is a storage component that sees the bit streams as objects.
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From page 25... ...
on a stable virtual machine.
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From page 26... ...
An alternative is to store a program executable on a virtual machine; this keeps the original format and only converts it to a simple bitmap image (a logical view) for presentation on demand.
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From page 27... ...
The program can be written for a virtual machine; it would essentially generate on demand a structure that contains both the tagged data elements of the document and their explicit presentation attributes, down to the individual char acters' images. Reconstructing a page is then easy; there is no need for any original word processor or viewer.
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From page 28... ...
In the future, a virtual machine emulator will make it possible to execute the emulator of the original machine, providing an original machine that then executes the original application code. The metadata must simply contain a user's guide on how to run the program.
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From page 29... ...
Relying on a Stable Virtual Machine The method of preservation that relies on a stable virtual machine consists of archiving with the original file, a decoding program P, which understands the internal structure and presents the information in a logical view (a hierarchical structure of tagged elements similar to those used in XML)
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From page 30... ...
Relying on a Stable Virtual Machine As explained above, a virtual machine can be used to preserve the decoding of an original file. The same applies to a file obtained by an initial conversion of the original file onto a new format.
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From page 31... ...
Also, the advantages of migration on access are reduced in proportion to the fraction of data types that end up being accessed in the future. GROWING USER EXPECTATIONS Users of online services, such as e-commerce sites, Web search engines, and the like, have developed expectations for near-immediate access to vast data sets.
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From page 32... ...
Therefore, third parties should be encouraged to develop user services beyond the basic level provided by NARA, an option discussed in Chapter 3 of this report. OTHER TECHNOLOGY TRENDS Full-Content Search and Automated Metadata Extraction One of the major challenges for the ERA system is that of ingesting the anticipated volumes of records without being bogged down by too much (costly)
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From page 33... ...
One approach to reducing this burden is full-content searching. There has been considerable progress in this area -- that an enormous body of publicly accessible Web pages can be searched effectively by search engines such as Google is a major achievement of relevance to NARA -- and there is widespread demand for better searching technologies.
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From page 34... ...
The errors that occur will tend to have a minimal impact on the precision (the proportion of items retrieved that are relevant) of finding aids, although they obviously will reduce recall (the proportion of relevant items retrieved by a search)
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