This paper describes how information collected by enterprise system management (ESM) platforms can be utilized in a novel approach to assess the information assurance delivered by an information system. We describe the assessment approach first and then explain the interaction patterns between the ESM platform and the assessment mechanism in the context of our prototype implementation. Keywords- mission assurance; cyber-security; quality of service; runtime assessment; fault toleranc; ESM; Nagios; OSSEC; SNMP