Multidrop (daisy chain) network
 

The switches are connected together with one twisted pair in a daisy-chain configuration.
The distance between 2 neighbour switches can reach 13 Km if 0,9 mm diameter wires are used or 6.5 Km with 0.4 mm diameter wires.
The date rate ranges from 192 Kb/s to 2.3 Mb/s
Failsafe ring network
 

If high availability is needed, the last switch is looped back to the first one through one line; if one line breaks or one switch fails, network communication is restored after a short recovery delay.
The recovery delay in case of line break is a few seconds depending on the number of switches connected to the ring.
The alarm relay is opened and an SNMP trap message is transmitted over the network.
The link failure and link recovery events are recorded in the non-volative log.