Over the Top video streaming services has grown very rapidly in recent years, with the emerge of diverse online video stores. One of the popular over the top services is Netflix. The significant increase of user data consumption by this type of services affects the performance of communications networks, and operators need methods to estimate how well the network behaves. In this paper a network traffic analysis of Netflix is presented. The traffic study has been performed with diverse devices and access technologies. A model for quality of experience (QoE) evaluation, based on application performance metrics, has been applied to estimate Mean Opinion Score (MOS) by end users.