Best practices for storage infrastructure
Best practices emerge over time as a result of a deeper understanding of a problem and outcomes from pilot projects or test beds established for experimentation. While the anthropological community is just beginning to explore storage solutions for LTP (long-term preservation) the Digital Library community has for nearly a decade explored the principal issues and challenges that surround storage and backup of digital data. The principal problems that need to be addressed are well known and include (1) technological obsolescence; (2) media decay (3) replication, and (4) evolving standards to manage large storage pools or networked storage grids.
As already discussed, the worst-case scenario for storage and backup is locally managed storage. This modality is associated with a high probability of data loss over time. In this mode, best practices followed by traditional data centers to protect data and secure unauthorized access to data is nearly impossible to maintain. The challenge is to educate the community on the need to abandon this practice and adopt alternative solutions such as participation in grid storage networks.
At the opposite end of the spectrum and across the Atlantic the European community has successfully demonstrated the efficacy of grid storage for LTP of digital data. The infrastructure for grid storage has trusted governance, which establishes best practices to deal with data management problems, associated with the aforementioned problems inherent in storage hardware and software used to manage storage. One might characterize grid storage as “being alive”, continuously being refreshed and secure since access and replication where an integral part of the management functionality of the grid. In addition, participation in the grid also relieves the student or researcher with the responsibility to plan and manage his or her own media migrations. (More)
Optical disk, magnetic disk and tape have all been successfully used for data storage and backup. In most instances these media are combined to form a hierarchical storage system. Typically these systems deploy magnetic disk for fast online access to data and tape or optical disk to store off-line data that is infrequently accessed. The goal is to build a configuration that satisfies LTP requirements at a price performance that is affordable and sustainable. Finally the group unanimously recognized that storage and backup did not equate to long-term preservation of digital data. In the absence of a logical layer, such as PREMIS (PREservation Metadata: Implementation Strategies) to overlay storage, over time digital data would become more difficult to: discovered, search, accessed or understood as hardware software and community standards evolved and made older storage and access system obsolete.
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