communication reliability of SCADA system, security communication
strategy and redundancy mechanism. The security communication strategy
ensured reliable communication between SCADA RTU and server. It can
avoid the system being disturbed or breached by invalid message.
Simultaneity, the realization of redundancy mechanism improved the
reliability of SCADA communication network [1 6 ].
Carlos Q., et al. in 2009 proposed the architecture of a modular
SCADA testbed and described their tool which mimics a SCADA network,
monitors and controls real sensors and actuators using Modbus/TCP
protocol (Modicon bus/ transmission control). Using Distributed Denial of
Service (DDoS) scenarios, they showed how attackers can disrupt the
operation of a SCADA system. Their proposed testbed architecture was
based on a combination of network simulation and real devices
connectivity. It allowed real world devices (such as sensors, and actuators)
to be attached to the simulator to study the effects of malicious attacks on
the devices and on the simulated network. Many argue that simulations do
not represent real world scenarios accurately. So their proposed
architecture aimed to provide more realistic evaluations by adding real
devices into the simulation [1 7 ].
Xiang-ming G., et al. in 2009 presented the construction method
about SCADA system for urban pipeline network based on GPRS (General
Packet Radio Service) and wireless sensor network through researching the
characteristics of wireless sensor network as well as Zigbee technology.
Their Experiment results showed that the SCADA system based on GPRS
and wireless sensor network improved the real-time property, reliability
and integrity of pipeline network data with increasing the sensor node
density in the monitored region [ 18 ].