In the past several decades, and at an increasing pace, many records that used to be stored on paper have been stored digitally on computer information systems, instead. As older technologies are replaced by newer generations of hardware and software, new schemes for storing and coding the data are introduced. Because of the rapid evolution of technology, future digital systems may not be able to read and/or interpret the digital records made and stored on these older systems, even if those records are still in good condition. We are losing the knowledge of how the old systems stored and coded information. Increasingly, therefore, when we attempt to access and recover those aging documents, we will find that we no longer have the necessary information to do that. This paper addresses the problem of maintaining long-term access to digital documents and provides a methodology for overcoming access difficulties due to technological obsolescence. We created a model, called the Digital Rosetta Stone, that provides a methodology for maintaining long-term access to digital documents. The underlying principle of the model is that knowledge preserved about different storage devices and file formats can be used to recover data from obsolete media and to reconstruct the digital documents. We describe three processes that are necessary for maintaining long-term access to digital documents in their native formats--knowledge preservation, data recovery, and document reconstruction
