stjärnringtopologi

Stjärnringstopologi is a hybrid network topology that combines features of both star and ring topologies. In a stjärnring network, the physical layout is that of a star, meaning all devices are connected to a central hub or switch. However, the internal connection within this central device, or the connections between multiple hubs, form a logical ring. Data travels in a circular path through the network.

Each device in the star segment communicates directly with the central hub. If the central hub is a simple repeater, it might pass data along the ring. If it's a more intelligent switch, it can direct traffic more efficiently. The ring aspect of the topology ensures that data circulates, and a token-passing mechanism is often used to manage access to the network, preventing collisions.

The advantage of stjärnringtopologi is that it offers some of the robustness of a ring network, where a single cable break in a pure ring can bring down the whole network. In a stjärnring, if a cable from a device to the hub fails, only that device is affected. However, if the central hub or the ring connection within it fails, the entire network can be disrupted, similar to a pure star topology. This topology was more common in older token ring networks that were implemented with a physical star cabling system to simplify installation and troubleshooting compared to a pure physical ring.