Wireless Sensor Networks (WSNs) are a new technology that is expected to be used increasingly in the near future due to its cheap cost and data processing ability. However, securing WSNs is a complicated issue since the chosen security scheme should offer data security requirements such as data integrity, confidentiality, authentication, and availability although of the existed resource constraints in the sensors. In this paper, we describe the design of securing end-to-end data in WSNs using a Mixture of Asymmetric and Symmetric Approaches (MASA) that improves the security level offered by similar schemes and reduces the resources consumptions.