Computer network topology refers to the physical communication schemes used by connected devices on a network. The basic computer network topology types are:BusRingStarMeshTreeWireless
Networks that are more complex can be built as hybrids using two or more of these basic topologies.
Bus Network Topology
Bus networks share a common connection that extends to all devices. This network topology is used in small networks. Every computer and network device connects to the same cable, so if the cable fails, the whole network is down, but the cost of setting up the network is reasonable.
This type of networking is cost-effective. However, the connecting cable has a limited length, and the network is slower than a ring network.
Ring Network Topology
Each device in a ring network is attached to two other devices, and the last device connects to the first to form a circular network. Each message travels through the ring in one direction — clockwise or counterclockwise — through the shared link. Ring topology that involves a large number of connected devices requires repeaters. If the connection cable or one device fails in a ring network, the whole network fails.
Although ring networks are faster than bus networks, they are more difficult to troubleshoot.
Star Network Topology
A star topology typically uses a network hub or switch and is common for in-home networks. Every device has its own connection to the hub. The performance of a star network depends on the hub. If the hub fails, the network is down for all connected devices. The performance of the attached devices is usually high because there are usually fewer devices connected in star topology that in other types of networks.
A star network is easy to set up and easy to troubleshoot. The cost of setup is higher than for bus and ring network topology, but if one attached device fails, the other connected devices are unaffected.
Mesh Network Topology
Mesh network topology provides redundant communication paths between some or all devices in a partial or full mesh. In full mesh topology, every device is connected to all the other devices. In a partial mesh topology, some of the connected devices or systems are connected to all the others, but some of the devices only connect to a few other devices.
Mesh topology is robust and troubleshooting is relatively easy. However, installation and configuration are more complicated than with the star, ring, and bus topologies.
Tree Network Topology
Tree topology integrates the star and bus topologies in a hybrid approach to improve network scalability. The network is set up as a hierarchy, usually with at least three levels. The devices on the bottom level all connect to one of the devices on the level above it. Eventually, all devices lead to the main hub that controls the network.
This type of network works well in companies that have various grouped workstations. The system is easy to manage and troubleshoot. However, it is relatively costly to set up. If the central hub fails, then the network fails.
Wireless Network Topology
Wireless networking is the new kid on the block. In general, wireless networks are slower than wired networks. With the proliferation of laptops and mobile devices, the need for networks to accommodate wireless remote access has increased vastly.
It has become common for wired networks to include a hardware access point that is available to all the wireless devices that need access to the network. With this expansion of capabilities comes potential security problems that must be addressed.