We develop an abstract operational model for configuration management under service-oriented computing. This semantics is based on a graph-based representation of the configuration of global computers and an operational model of service-oriented dynamic reconfiguration based on a resolution-like mechanism similar to concurrent constraint programming. A resolution step involves a goal executed by a business activity and a clause that corresponds to a complex service. Unification captures service discovery, ranking and selection based on SLA-constraint optimisation and interpretations between specifications of conversations expected by the goal and provided by the discovered service. The resolvent is a reconfiguration of the original business activity that results from binding the goal with the discovered service.