n.the corruption of the lowest level of digital dataLavoie 2008At that time, digital preservation was often characterized as a discrete activity that could be segregated from, or tacked onto the end of, the digital life cycle; the primary obstacle to be overcome was the development of technical strategies, like emulation and migration, to stave off the twin evils of bit rot and technological obsolescence.Lee and Tibbo 2011, 127In contrast to caring for analogue materials, digital curation brings a wide array of opportunities and challenges. Opportunities include both wider and integrated access, representation of an increased range of human experience, persistence through redundant copying, economies of scale, and enrollment of collective expertise. Challenges include bit rot, obsolescence, social inertia, technology monitoring, intellectual control, access environments, and the ability to convey meaning over time.Stuchell 2015Digital content is also prone to unseen degradation where a 1 may randomly change to 0 due to aging media and other factors, a risk called bit-flip or bit-rot.Cocciolo 2016a, 129–130File fixity checks look for hardware or software failures that could render a file inaccessible or inaccurate. This is often referred to as bit-rot or bit-flipping and is usually addressed by running a file fixity check such as applying the MD5 checksum generator to a file upon ingest and verifying the checksum remains the same through time. If the file changes somehow (a bit is flipped), the file can be restored from backup.Corrado and Moulaison Sandy 2017, 317An event that occurs usually gradually, when bits of a file change over time. Bit rot can be due to physical deterioration of memory in storage media or to environmental factors affecting that media. Over time bit rot may cause the data or files to become unreadable.NYSA 2023b, 5The original copy of a record is usually retained even if the file has been converted to a digital preservation format for long-term use. In cases such as these, the original can be retained in nearline or offline storage, since the need for access to it is minimal. Originals require storage that keeps the files from suffering bit rot and being affected by outside intrusions.
