1st International ICST Conference on Forensic Applications and Techniques in Telecommunications, Information and Multimedia

Research Article

Timestamp evidence correlation by model based clock hypothesis testing

  • @INPROCEEDINGS{10.4108/e-forensics.2008.2637,
        author={Svein Yngvar  Willassen},
        title={Timestamp evidence correlation by model based clock hypothesis testing},
        proceedings={1st International ICST Conference on Forensic Applications and Techniques in Telecommunications, Information and Multimedia},
        publisher={ACM},
        proceedings_a={E-FORENSICS},
        year={2010},
        month={5},
        keywords={Digital investigation event logic clock hypothesis},
        doi={10.4108/e-forensics.2008.2637}
    }
    
  • Svein Yngvar Willassen
    Year: 2010
    Timestamp evidence correlation by model based clock hypothesis testing
    E-FORENSICS
    ACM
    DOI: 10.4108/e-forensics.2008.2637
Svein Yngvar Willassen1,*
  • 1: Department of Telematics, Norwegian University of Science and Technology, O.S. Bragstads plass 2B, 7491 Trondheim, Norway +47 92449678
*Contact email: svein@willassen.no

Abstract

Timestamps play an important role in digital investigations, since they are necessary for the correlation of evidence from different sources, including network tracing. Use of timestamps as evidence can be questionable due to the reference to a clock with unknown adjustment. This work addresses this problem by taking a hypothesis based approach to timestamp investigation. Historical clock values can be formulated as a clock hypothesis. This hypothesis can be tested for consistency with timestamp evidence by constructing a model of actions affecting timestamps in the investigated system. Acceptance of a clock hypothesis with timestamp evidence can justify the hypothesis, and thereby establish when events occurred in civil time. The results can be used to correlate timestamp evidence from different sources, including identifying correct originators during network trace.