Safer asynchronous runtime monitoring using compensations

Abstract

Asynchronous monitoring relieves the system from additional overheads induced through online runtime monitoring. The price paid with such monitoring approaches is that the system may proceed further despite having reached an anomalous state. Any actions performed by the system after the error occurring are undesirable, since for instance, an unchecked malicious user access may perform unauthorized actions. In this paper we investigate the use of compensations to enable the undoing of such undesired actions, thus enriching asynchronous monitoring with the ability to restore the system to the original state just after the anomaly had occurred. Furthermore, we show how adaptive synchronisation and desynchronisation of the monitor with the system can also be achieved and report on the use of the proposed approach on an industrial case study of a financial transaction handling system.