Abstract
Intrusion Detection and/or Prevention Systems (IDPSs) are now a crucial defensive measure to defend against attacks intended to breach the security and operation of enterprise information systems. The IDPS configuration can, however, have a negative impact on network performance in terms of end-to-end delay and packet loss. This paper proposes an analytical queuing model based on the embedded Markov chain which analyzes the performance of the IDPS and evaluates its impact on performance. Through extensive simulations, we validate the proposed model and the numerical equations that estimate various performance metrics. Our results show that this model can be leveraged to assess and set up an effective configuration for the IDPS, achieving simultaneously the trade-off between security enforcement levels on one side and network Quality of Service (QoS) requirements on the other.