Fundamentals of AV Preservation - Chapter 4

Section 1: Digital preservatIOn concepts

1.1 Definitions

“Digital preservation is the active management of digital content over time to ensure ongoing access.”¹ It is an integral part of a larger process of curation, which consists of the activities across the content lifecycle described throughout this textbook: selection and appraisal, description, ongoing care and management, long-term access, and/or deaccessioning/disposal. 

Without active management which includes many of the activities outlined in this chapter, digital assets and their associated content are at risk, potentially through media failure, human error, inaccessibility due to format obsolescence, or barriers to discoverability due to poor metadata. The functions of digital preservation reduce these risks and together help to ensure that content remains accessible over time.

1.2 Risk Management

At the heart of a preservation strategy is risk management. The opportunities for loss or damage to digital collections is inherent in providing access to users, who may include digital collections managers, IT staff, students, the public, and others. A preservation strategy can be an effective way to mitigate these risks to the greatest extent possible.  

The nature of risks are varied and may be human-generated, mechanical, or natural. The human risks to technology may be purposeful (file formats are not selected for migration, metadata is not captured), nefarious (viruses, cyber-attacks), or accidental (deletions, misfiling or misnaming files). Organizational risks include insufficient planning and policies, which lead to a loss of or lack of sustainable funding to support trained staff and/or appropriate technologies. Risks may also be mechanical, such as when files change at the bit level without human awareness or media and storage fail. Risks may also come from nature; floods and fires can destroy electronic media on which files are stored. 

Over time, risks evolve based on the organization and its resources as well as industry-wide technical changes. As risks change, how institutions identify, respond, and monitor them must change, too. Successful preservation strategies must be flexible, yet cautious, to be able to react to risk effectively. Through planning and management, risks can be mitigated as they emerge.

1.3 Preservation Management

Due to the varied nature of risks to digital assets, it is important that digital preservation be approached from a programmatic standpoint with administrative support that makes preservation a priority. One approach to thinking about preservation management is illustrated by the concept of the “three-legged stool,” in which the organizational infrastructure, technological infrastructure, and resources all have equal footing to create a stable digital preservation program.Nancy McGovern’s Digital Preservation Management: Implementing Short-term Strategies for Long-term Problems  describes these three interlocking structures as follows:

• Organizational Infrastructure includes the policies, procedures, practices, and people—the elements that any programmatic area needs to thrive but that are specialized to address digital preservation requirements.
   
• Technological Infrastructure consists of the requisite equipment, software, hardware,  secure environment, and skills to establish and maintain the digital preservation program. It anticipates and responds wisely to changing technology.
   
• A sustainable Resources Framework addresses the requisite startup, ongoing, and contingency funding to enable and sustain the digital preservation program.² 

Determining the “what” (organizational infrastructure), the “how” (technological infrastructure), and the “how much” (resources framework) helps to identify an institution’s needs for a sustainable digital preservation program.

1.4 Standards

Many industries employ standards to make certain they comply with accepted practice, ensure the safety of their customers and employees, and provide a foundation upon which new technologies can be built. Two international standards documents serve as the cornerstone for the management of digital collections, guiding institutions in the development of sustainable preservation programs and serving as benchmarks for institutions that are maintaining preservation management technologies. These are: 

• ISO 14721:2012, Space data and information transfer systems -- Open archival information system (OAIS) -- Reference model, commonly referred to as the OAIS Reference Model, or OAIS, and;
  
  
• ISO 16363:2012, Space data and information transfer systems -- Audit and certification of trustworthy digital repositories.

1. OAIS Reference Model

The Open Archival Information System (OAIS) reference model is a conceptual framework for an archival system dedicated to preserving and maintaining access to digital assets over the long-term. Because it is a conceptual model, it is not inherently prescriptive. Instead of specifying technology, staffing, or resources, it provides guidance about best practice for building a sustainable preservation environment. OAIS states that archival storage is necessary, but does not specify how that storage will be implemented, the technology required, or how many staff are needed to maintain it. Likewise, access is a component of the OAIS model, although how access is provided will be unique to each organization. Each component represents a process within a system but not the specific resources and technology required to support that process.

FIGURE 4.1 Open Archival Information Iystem (OAIS) Reference Model Credit: AVP