Internet is a large network of networks that spans the entire globe. Internet is playing indispensable role in our daily lives. The physical things are connected to internet with the help of digital identity. With recent advancement of information and communication technologies IoT became vital part of human life. However, IoT is not having standardized architecture. Nowadays IoT is integrated with fog computing which extends platform of cloud computing by providing computing resources on edges of computer network. Fog computing is motivated by IOT and It is decentralized solution for IoT. In addition, Fog computing has supported features like geographic distribution, low latency, location awareness, operate on premise, installed on heterogeneous hardware. IoT with cloud computing does not have such features. Therefore, in this paper, at first we discuss about the distributed fog computing architecture. Subsequently, we address the problem of authentication and design a new authentication framework for fog enabled IOT environment. It is stated that the proposed authentication framework will be useful in many IoT applications such as healthcare system, transportation system, smart cities, home energy management etc
