Advancement in communication technologies and the Internet of Things (IoT) is driving smart cities adoption that aims to increase operational efficiency and improve the quality of services and citizen welfare. It is estimated that by 2020, 75% of cars shipped globally will be equipped with hardware to facilitate vehicle connectivity. The privacy, reliability and integrity of communication must be ensured so that actions can be accurate and implemented promptly after receiving actionable information. Because vehicles are equipped with the ability to compute, communicate, and sense their environment, there is a concomitant critical need to create and maintain trust among network entities in the context of the network's dynamism, an issue that requires building and validating the trust between entities in a small amount of time before entities leave each other's range. In this work, we present a multi-tier scheme consisting of an authentication and trust building/distribution framework designed to ensure the safety and validity of the information exchanged in the system.