Abstract
Animals have a great importance in terms of beauty of landscape and are ingredient in medicines for humans. Destruction of habitat, increased pollution and illegal hunting have caused some species of animals to become endangered. Therefore, there is a need to protect such species of animals. This work uses Wireless Sensor and Actuator Networks (WSANs) to protect them from the hunters. Firstly, WSANs are modeled using graph theory and then flow chart of the problem is presented. Endangered Species Protection Algorithm (ESPA) is proposed which employs temperature and multimedia sensors for detecting hunters, predicting a safe location for animals and actuating them to move towards that location. The graph based model, flow chart and the proposed algorithm are transformed into an equivalent formal model. Formal specification of the algorithm is developed using Vienna Development Method Specification Language (VDM-SL). VDM-SL is used because it is a detailed level formal specification language. Both static and dynamic models are developed using VDM-SL which includes invariants over the components to restrict behavior and pre/postconditions for correct execution of functions and operations of the system. The developed formal specification has been analyzed through VDM-SL Toolbox for correctness of the system.