??? 11/26/05 15:45 Read: times |
#104201 - ring protection Responding to: ???'s previous message |
Jan Waclawek said:
However, the "ring" configuration has the drawback that all nodes must be up and working, in other words, if the probability that one of the node fails is P, the probability that the whole network of N nodes fails is 1-(1-P)N. If the "home automation" is supposed only to collect data and perform noncritical operations, it is OK, but if you want e.g. to control lights or heating, this is a bad approach. Jan Waclawek One could use some means of ring protection. Using a relay to connect upstream to downstream connector in case a node is failing can effectively restore the ring topology. Of course, the distance between two adjacent nodes will increase if an intermediate node fails. This ring protection mechanism was used in a (now obsolete) 10 mbit token ring network from Proteon. I think the IBM token ring network had a similar protection. regards Patrick |