We have come across the data transmission technologies over communication links in a network over wired as well as wireless mediums. Communication networks are generally having different types of communication links. For a direct connection of two nodes in a network, the communication links will be a point-to-point link, whereas for multiple nodes, the connection will be through a multiaccess or broadcast link. For those situations, when we find the nodes/stations are not having a direct link or connection to each other, we need some sort of mechanism to have the communication setup between those nodes. That mechanism is broadly referred to as the switching concept in the communication network. In this chapter, we are going to examine the technology of circuit switching and the packet switching, whose evolution is a remarkable achievement in the history of telecommunication that has taken place over the years. The switching concept forms a very important component of a communication network. It refers to the mechanism of connecting the incoming path to the desired outgoing path and directing the messages to reach the destination.