n.the property of being unchangedBlouin 1981, 157Print permitted such fixity, and the implications were significant and wide reaching. Print insured preservation through multiple copies, contributed to a democratization of access to information, contributed to the definition and preservation of language, defined vernaculars, increased the possibility of private possession of knowledge through copyright.Blouin 1996, 472The point here is that there was an era when the fixity and authenticity of texts were a great problem.Guercio 2001, 240The risks do not concern the professional nature of archival work which, in the context of the major transformation currently happening, can still change radically, so much as the very object of archival study: records, their specificity, their relationships, the format of their aggregations, the modalities of selection, and the periods of retention, the need for guaranteeing authenticity over time and of respecting the naturalness, fixity, and the necessity of the record links to the process of accumulation, which constitute the essential, if not exclusive, rationale for permanent preservation across time (for the use of the records creator in the first instance and thereafter for the needs of historical and scientific research).Tschan 2002, 192The transient and fluid nature of electronic records, their lack of fixity as compared to the printed page, their dependence on technology and their rapid obsolescence, led Taylor to remark that in many respects we are returning to a “pre-Gutenberg environment.”Schmidt 2011b, 268MD5 is a message digest algorithm, or cryptographic hash function, used to verify the integrity, or “fixity,” of digital files.Gilliland 2014a, 174The fixity that in the traditional archival paradigm is so integral to the status of both record and reliable record, in electronic records today comes not from their affixedness to a medium, but rather, in light of their inherent manipulability and transportability, from the ability to document the original record and to re-create an authentic copy of it.NDSA 2014, 1Fixity in this context is the property of a digital file or object being fixed or unchanged. In this sense, it is synonymous with bit-level integrity. Fixity information offers evidence that one set of bits is identical to another. The PREMIS data dictionary defines fixity information as “information used to verify whether an object has been altered in an undocumented or unauthorized way.” The most widely used tools for creating fixity information are checksums (like CRCs) and cryptographic hashes (like MD5 and various SHA algorithms), but there are other methods such as expected file size and file count that provide basic fixity information. The instruments for creating fixity information are explained later in this document, but before getting to those, it is worth pausing to discuss some of the limitations of fixity information and explain the diverse range of reasons to collect, check, maintain, and verify fixity information.Cocciolo 2016a, 133However, a limitation of this approach is that most commercial DAMs have little or no digital preservation functionality, such as tools for monitoring file format obsolescence or file fixity.Pendergrass et al. 2019, 188The intervals at which organizations check fixity vary considerably.
