A fail-safe self-routing fiber-optic ring network using multitailed receiver-transmitter units as nodes

A fiber-optic component consisting of N receivers, each with one fiber input port, and one transmitter with n fiber output ports, with a circuit in between, form a multitailed node. This is the basic building block for a self-routing `filled-ring network´ with many stations, which can be disconnected without affecting the ring integrity. The token-passing medium-access protocol is found to have a several times better performance, in terms of the average delay-traffic intensity characteristic, in a filled-ring network than in a conventional ring network with the same number of stations. In a realistic example with 64 stations the improvement is by a factor of two to three. Using the multitailed nodes and self-routing, the network can easily be expanded to more complex configurations without introducing a routing overhead to keep the network under control