Fault tolerance support of smart-M3 application on the software infrastructure level

The Smart-M3 platform allows constructing software applications consisting of agents that interact by sharing information in a smart space. An important problem is achieving the dependability of applications in case of failures, a common situation for existing networked environments. The most sensitive operation is subscription-a persistent networked query. In this paper, we consider a generic software infrastructure for a Smart-M3 application and propose infrastructure-level solutions to support the application fault tolerance. Our first solution augments the infrastructure with a content service. It improves safety (preservation) and integrity of volumetric data due to the delegation of storage functions to a separate element of the application infrastructure. The service employs the wellknown matured web technology. The second solution consists of mechanisms for the fault tolerance support to detect failures of subscription and to recover effectively. For case study, we use an existing Smart-M3 application-the SmartRoom system. Our evaluation confirms that our solutions lead to better dependability without essential degradation of the performance.