  Networks exist all around on the planet, and inside the brain of every living
organism. On the city streets we see transport networks, inside homes and
organizations we see water piping networks. And in the digital information age
we see the rise of the computer networks and the mobile networks and their
upgrade from generation to generation. We need networks for efficient sharing
of resources and as human beings the most valuable thing that we can share
along the time from age to age is our data that could represent our knowledge
and information represented through text, voice, image, and video. In this
paper we provide a quick overview on network generation and IoT applications.
Also, we point to the security threats in these generations.
