We introduce a new paradigm, based on an extension of the Open Cloud Computing Interface (OCCI), for the on-demand monitoring of the cloud resources provided to a user. We have extended the OCCI with two new sub-types of core entities: one to collect the measurements and the other to process them. The user can request instances of such entities to implement a monitoring infrastructure. The paradigm does not target a specific cloud model, and is therefore applicable to any kind of resource provided as a service. The specifications include only the minimum needed to describe a monitoring infrastructure, thus making this standard extension simple and easily adoptable. Despite its simplicity, the model is able to describe complex solutions, including private/public clouds, and covers both infrastructure and application monitoring. To highlight the impact of our proposal in practice, we have designed an engine that deploys a monitoring infrastructure using its OCCI-compliant descriptions. The design is implemented in a prototype that is available as open source. 
Application level interface for a cloud monitoring service