A scalable and lightweight QoS monitoring technique combining passive and active approaches

To make a scalable and lightweight QoS monitoring system, we have proposed a new QoS monitoring technique, change-of-measure based passive/active monitoring (CoMPACT monitor), which is based on change-of-measure framework and is an active measurement transformed by using passively monitored data. This technique enables us to measure detailed QoS information for individual users, applications, and organizations, in a scalable and lightweight manner. In this paper, we present the mathematical foundation of CoMPACT monitor. In addition, we show its characteristics through simulations in terms of typical implementation issues for inferring the delay distributions. The results show that CoMPACT monitor gives accurate QoS estimations with only a small amount of extra traffic for active measurement.