Document Type

Conference Paper

Publication Date


Publication Title

Proceedings of the 2018 Web Archiving and Digital Libraries Workshop



Conference Name

Web Archiving and Digital Libraries Workshop (WADL 2018), June 6, 2018, Fort Worth, Texas


[Introduction] Checking fixity in web archives is performed to ensure archived resources, or mementos (denoted by URI-M) have remained unaltered since when they were captured. The final report of the PREMIS Working Group [2] defines information used for fixity as "information used to verify whether an object has been altered in an undocumented or unauthorized way." The common technique for checking fixity is to generate a current hash value (i.e., a message digest or a checksum) for a file using a cryptographic hash function (e.g., SHA-256) and compare it to the hash value generated originally. If they have different hash values, then the file has been changed, either maliciously or not. We implicitly trust content delivered by web archives, but with the current trend of extended use of other public and private web archives, we should consider the question of validity of archived web pages. Most web archives do not allow users to retrieve fixity information. More importantly, even if fixity information is accessible, it is provided by the same archive delivering the content. A part of our research is dedicated to establishing and checking the fixity of archived resources with the following requirements:

  • Any user can generate fixity information, not only the archive
  • Fixity information can be generated on the mementos playback


© 2018 Edward A. Fox, Martin Klein, Zhiwu Xie.

Included with the kind written permission of the copyright holders and the author.

Now published under a Creative Commons Attribution-NonCommercial NoDerivatives 4.0 International (CC BY-NC-ND 4.0) License.

Original Publication Citation

Aturban, M., Nelson, M. L., & Weigle, M. C. (2018) It is hard to compute fixity on archived web pages [Conference Paper]. Web Archiving and Digital Libraries Workshop (WADL 2018), Fort Worth, Texas.


0000-0001-7648-9082 (Aturban), 0000-0003-3749-8116 (Nelson), 0000-0002-2787-7166 (Weigle)