Network Topologies, Communication Protocols, and Standards

Every network has a topology that determines the way in which different devices of the network are arranged and how they communicate with each other. Here we need to distinguish between physical and logical topologies. The former refers to the physical layout of the network, i.e., the way that devices are physically connected to the network, either through actual cables or direct wireless communication links. By contrast, the logical topology of a network refers to the manner that data flows through the network from one node to the other without worrying about the physical interconnection of the devices for transporting a packet from a source to a destination device. The two lower layers of the Open Systems Interconnection (OSI) reference model (ISO/IEC international standard, Information technology – open systems interconnection – basic reference model: the basic model, 2nd edn, 1994) , the physical and data link layer, define the physical topology of a network, while the network layer is responsible for the logical topology.