Wireless Sensor and Actor Networks emphasize the necessity for cooperative communication between actors as well as sensors in order to achieve ubiquitous monitoring and efficient interaction in realistic physical environments and appropriate acting on them. This collaboration aims to assure appropriate decision making related to specific event detection, appropriate classification as well as selection of the optimal actor able to react to the event. Therefore this paper aims to propose a suitable architecture providing a data fusion model necessary for the first goal as well as a task assignment method comprising an essential component for energy efficient communication between the actors so as to allocate the acting tasks.