This thesis shows the analysis of Smart Metering study cases in the domain of Internet of Things with the strong focus on the environment of Fog Computing. Analysis is done through an implemented simulation model in YAFS programming tool. 1st chapter is a brief summary of everything covered trough this thesis. 2nd chapter explains what simulated environments are, for what they are used for and why are they becoming more popular in the recent years across all domains of workplace. It gives a list of many types of simulation models with the focus on explanation of most commonly used, discrete event simulators. Alongside that, it explains basic concepts of Simpy library which is used for implementing those type of simulations. 3rd chapter gives the explanation on the difference between Edge Computing, Fog Computing and Cloud Computing.4th chapter explains the term Internet of Things, gives an insight of its architecture and the idea behind it. Also, it gives an insight of wide variety of questions which come up when considering the wide domain of Internet of Things term. 5th chapter explains wide variety of YAFS simulator concepts, from its architecture, application modeling, dynamic policies, result analysis, up to comparison to other fog simulators and implementation details that explain how Simpy library is used inside of YAFS core. The last chapter explain the implementation steps of Smart Metering study case where smart metering is done on edge devices who are connected over LoRaWAN Network to the gateways which pass on the packets to all kind of different submodules in the fog network which process and pass those informations to central cloud module. At the very end, a detailed analysis of such systems is given, with a demonstration of possible problems and solutions for higher network security and easier real-world system implementation.