Implementing a reflective fault-tolerant CORBA system

The use of reflection is becoming popular today for the implementation of non-functional mechanisms such as fault tolerance. The main benefits of reflection are separation of concerns between the application and the mechanisms and transparency from the application programmer point of view. Unfortunately, metaobject protocols (MOPs) available today are not satisfactory with respect to necessary features needed for implementing fault tolerance mechanisms. Previously, we proposed a specialised MOP based on Corba, well adapted for such mechanisms (M.-O. Killijian and J.C. Fabre, 1998). We deliberately focus on the implementation of this metaobject protocol using compile-time reflection and its use for implementing distributed fault tolerance. We present the design and the implementation of a fault-tolerant Corba system using this metaobject together with some preliminary experimental results. From the lessons learnt from this work, we briefly address the benefits of reflection in other layers of a system for dependability issues.