Research Article
Performance Issues About Context-Triggered Piecewise Hashing
@INPROCEEDINGS{10.1007/978-3-642-35515-8_12, author={Frank Breitinger and Harald Baier}, title={Performance Issues About Context-Triggered Piecewise Hashing}, proceedings={Digital Forensics and Cyber Crime. Third International ICST Conference, ICDF2C 2011, Dublin, Ireland, October 26-28, 2011, Revised Selected Papers}, proceedings_a={ICDF2C}, year={2012}, month={12}, keywords={Digital forensics techniques and tools context-triggered piecewise hash functions fuzzy-hashing efficiency of subtleties of fuzzy-hashing}, doi={10.1007/978-3-642-35515-8_12} }
- Frank Breitinger
Harald Baier
Year: 2012
Performance Issues About Context-Triggered Piecewise Hashing
ICDF2C
Springer
DOI: 10.1007/978-3-642-35515-8_12
Abstract
A hash function is a well-known method in computer science to map arbitrary large data to bit strings of a fixed short length. This property is used in computer forensics to identify known files on base of their hash value. As of today, in a pre-step process hash values of files are generated and stored in a database; typically a cryptographic hash function like MD5 or SHA-1 is used. Later the investigator computes hash values of files, which he finds on a storage medium, and performs look ups in his database. Due to security properties of cryptographic hash functions, they can not be used to identify similar files. Therefore Jesse Kornblum proposed a similarity preserving hash function to identify similar files. This paper discusses the efficiency of Kornblum’s approach. We present some enhancements that increase the performance of his algorithm by 55% if applied to a real life scenario. Furthermore, we discuss some characteristics of a sample Windows XP system, which are relevant for the performance of Kornblum’s approach.