In its simplest form, networking takes place between two devices that are directly connected. However, it is often impractical for devices to be directly connected, such as when devices are far apart or when more than two devices want to communicate. The solution is to attach each device to a communication network. Communication networks can be categorized on the basis of architecture and techniques to transfer data:

1. broadcast networks, where a transmission from any device is broadcast and received by all other stations;
2. circuit-switched networks, where a dedicated connection is established between devices on a network across switching nodes within the network;
3. packet-switched networks, where data are sent in smaller units, called "packets," from node to node within a network from source to destination.

Basic Configurations

The basic configuration, or topology, of a network is the geometric representation of all the links and nodes of a network. A...