Distributed control system (DCS) network architecture

The invention relates to a distributed control system (DCS) network architecture, which is characterized by comprising a common network segment and a beyond design basis accident (BDBA) network segment switch network which are connected, wherein a switch of the BDBA network segment is connected with an earthquake monitoring system and is controlled by a signal trigger of the earthquake monitoring system, so that functions between the common network segment and the BDBA network segment are automatically switched; equipment of the BDBA network segment is connected with an independent uninterruptible power supply, and the network and equipment of the BDBA network segment are quakeproof type I equipment; and the DCS network architecture also comprises a real-time data network and a non-real-time data network, wherein an upper computer and a server are simultaneously connected to the two networks, and hardware encryption chips are arranged in a controller and the upper computer. The code transmission reliability in the network is realized through the hardware encryption chips; corresponding networks and equipment in the DCS are effective under BDBA working conditions; the real-time data and non-real-time data are shunted, and the network load is reduced; and due to analog quantity sequence of event (SOE), recalling is facilitated after the accident happens.