Smart cities utilize what is known as fog computing properties, such as caching and cooperating, to protect the security of users' sensitive data. Fog computing in general was made as an extension of cloud computing to serve specified network parties. This method was developed with smaller storage and processing power, which allows data to be processed before reaching the cloud and quick response in emergency cases. This also allows for adaptability to mobile devices, as this is where most users store their sensitive information and personal data. The main focus to preserve privacy of mobile users is to mask their identity revolving around the use of pseudonyms, nicknames, or hash values. In this project, we will work on three different approaches to protect users privacy: Foggy Dummies, Bling Third Party, and Double Foggy Cache. The idea of Foggy Dummies is to generate smart dummies in order to shield users from security threats by swapping data within the fog before sending it to the service provider. Bling Third Party trusts a third part to broker the data between the user and the service provider and the Double Foggy Cache places two caches within the fog which act to broker the data between peers and protect the user from the service provider using a relationship of trust and cooperation. We will compare and analyze the advantages and disadvantages of each approach and figure out their best applications. This research allows us to conclude the secure nature of smart cities, and the multiple methods of protection which can be utilized. This secure nature will be extremely relevant to those considering utilizing fog computing to host a cloud environment and protect user data. While security has always been a concern within cloud environments, these methods allow for more options within these environments.