Nowadays as we know most DCS systems come out with a more distributed TREE network architecture for linking BTG (Boiler, turbine Gen) with BOP areas (AHP, CHP, DM plant,Air Compressors, CW/ACW pumps), common systems and other third part systems. This network involves L1 ,L2 , L3 switches up the hierarchy starting from Field to upper leveL HMI.
Some systems also employ redundant ring(Bus) topology for power plant DCS. With ring manager sitting at definite locations for fault detecting.
My questions is :
Which architecture TREE OR RING is better and why??