Privacy issues in intrusion detection systems: A taxonomy, survey and future directions

Intrusion Detection Systems (IDSs) detect potential attacks by monitoring activities in computers and networks. This monitoring is carried out by collecting and analyzing data pertaining to users and organizations. The data is collected from various sources - such as system log files or network traffic-and may contain private information. Therefore, analysis of the data by an IDS can raise multiple privacy concerns. Recently, building IDSs that consider privacy issues in their design criteria in addition to classic design objectives (such as IDS' performance and precision) has become a priority. This article proposes a taxonomy of privacy issues in IDSs which is then utilized to identify new challenges and problems in the field. In this taxonomy, we classify privacy-sensitive IDS data as input, built-in and generated data. Research prototypes are then surveyed and compared using the taxonomy. The privacy techniques used in the surveyed systems are discussed and compared based on their effects on the performance and precision of the IDS. Finally, the taxonomy and the survey are used to point out a number of areas for future research.