A Cross-layer Monitoring Solution based on Quality Models

In order to implement cross-organizational workflows and to realize collaborations between small and medium
enterprises (SMEs), the use ofWeb service technology, Service-Oriented Architecture and Infrastructure-as-a-
Service (IaaS) has become a necessity. Based on these technologies, the need for monitoring the quality of (a)
the acquired resources, (b) the services offered to the final users and (c) the workflow-based procedures used
by SMEs in order to use services, has come to the fore. To tackle this need, we propose four metric Quality
Models that cover quality terms for the Workflow, Service and Infrastructure layers and an additional one for
expressing the equality and inter-dependency relations between the previous ones. To support these models
we have implemented a cross-layer monitoring system, whose main advantages are the layer-specific metric
aggregators and an event pattern discoverer for processing the monitoring log. Our evaluation is based on the
performance and accuracy aspects of the proposed cross-layer monitoring system.