Deploying QoS contracts in the architectural level

Abstract

This paper presents an approach to describe, deploy and manage software architectures having dynamic functional and non-functional requirements. The approach is centered on an ADL extended with high-level contracts, which are used to specify the non-functional requirements associated to the architecture of a given application. These contracts are also used to configure the infrastructure required to enforce the non-functional requirements and, during the running time, can be used to guide architecture adaptations, in order to keep them valid in face of changes in the supporting environment. The infrastructure required to manage the contracts follows an architectural pattern, which can be directly mapped to specific components included in a supporting reflective middleware. This allows designers to write a contract and to follow standard recipes to insert the extra code required to its enforcement in the supporting middleware. © 2005 by International Federation for Information Processing.