A perspective–retrospective analysis of diversity in signature-based open-source network intrusion detection systems

The signature-based network intrusion detection systems (IDSs) entail relying on a pre-established signatures and IP addresses that are frequently updated to keep up with the rapidly evolving threat landscape. To effectively evaluate the efficacy of these updates, a comprehensive, long-term assessment of the IDSs’ performance is required. This article presents a perspective–retrospective analysis of the Snort and Suricata IDSs using rules that were collected over a 4-year period. The study examines how these IDSs perform when monitoring malicious traffic using rules from the past, as well as how they behave when monitoring the same traffic using updated rules in the future. To accomplish this, a set of Snort Subscribed and Suricata Emerging Threats rules were collected from 2017 to 2020, and a labeled PCAP data from 2017 to 2018 was analyzed using past and future rules relative to the PCAP date. In addition to exploring the evolution of Snort and Suricata IDSs, the study also analyses the functional diversity that exists between these IDSs. By examining the evolutionary behavior of signature-based IDSs and their diverse configurations, the research provides valuable insights into how their performance can be impacted. These insights can aid security architects in combining and layering IDSs in a defence-in-depth deployment.