Warboys et al. discuss a dynamic and evolvable architectural framework known as ArchWare, which is receptive to both predefined (static) and emergent (dynamic) behaviors. The self-producing framework incorporates a set of evolvable commercial off-the-shelf (COTS) components, a set of integration mechanisms known as transformer/connectors, a reflective environment composed of a set of flexible subsystems whose definitions can be changed, and users. The main contribution of this work is a dynamic architectural framework that will combine a library of COTS components, which can evolve based on change, and a set of tools built for different projects by the European community.

The paper is well written and well organized, and points out a number of interesting issues. To validate their approach, however, the authors used a set of supporting facts and assumptions. The main motivation for a so-called active architecture is to insure the flexibility and adaptability of a system to both the initial static configuration, and to the continuing reconfiguration of COTS components to capture the dynamic evolution of a system at the architectural level. Therefore, the discussion about the active architectural model needs to elaborate (at least) the following issues: how the active model maintains its state, and the mechanisms the model uses to control excessive flexibility, which may cause unwanted behaviors.