Wireless Data Communications for SCADA Systems 1
Advanced SCADA Features Networking (Communication Anywhere to Anywhere) Communication Network Data Reliability (No Communication Errors) Data Security (Immune to Intrusion) 2
Open Communication Solutions SCADA Wonderware Intellution Factorylink etc. Versatile Interface Applications Pressure/Flow Maintenance Leak detection etc. Versatile Media PLC Interface Allen Bradley Modicon Etc. MODBUS DNP 3.0 OPC MDLC over TCP/IP etc. 900 Mhz Conventional 900MHz S.Spectrum Analog Trunking VHF / UHF Conventional UHF-900 MHz MAS System Telco Network GSM/GPRS Satellite Microwave. Versatile IEDs Pressure Control Flow calculations Pumps Start etc. 3
A Communication Oriented 1/3 A powerful combination of two functions: Programmable Logic Controller Communication Modem Remote Control Communication Modem, Programmable Controller Local Control 4
A Communication Oriented 2/3 Store and Forward Repeater F1-F1 Reporting By Event Node Linking two Media Protocol Converter for PLC Links Local Control of Remote Sites Time Synchroniz ation 5
A Communication Oriented 3/3 PLC Local Process ++ + Network Comm. - +++ Polling via radio Report by Event 6
Store and Forward Links All radio links may use the same frequency! S&F S&F Repeater FIU SCADA HMI 7
Backup Links Enhance Reliability IP Gateway RF Line SCADA Control Center Radio RF Backup Radio RF Damaged Wire-line 8
Wide Area SCADA-Data Network Primary Water SCADA S&F Repeater Ethernet ToolBox IP Gateway Line Based network S&F Repeater for Pumping Station Ethernet Secondary MCC IP and Comm. Node for Reservoir 9
Complex SCADA System Printer Remote ToolBox Line Based IP Secondary MCC Local Ethernet Main ToolBox Remote Ethernet & Data Comm. Node (SLIP) Prime Link Primary MCC TS Wireline Comm. IP Gateway Wireline Comm. Prime Link Backup Link & Data Comm. Node Backup Link & Data Comm. S&F & Data Comm. Node Prime Link & Data Comm. Node 10
Reporting in Wireless SCADA Systems Cyclic Polling of s Complete Polling - Tell me about all your conditions Time consuming process not suitable for wireless media Report by Exception Tell me about only what changed Change of state that does not require immediate attention Cyclic Health Check - Indicate shortly that you are alive To minimize the health check cycle (leave time gaps for alarms) Initiating Unsolicited Messages Report By Event - Predefined Alarm conditions Must get immediate attention of the operator (critical alarms) Group Calls Burst messages Everyone Accept this Message No acknowledgement is expected ( all keep quite for 5 minutes ) 11
Multiple Address System Network F1 Using the 7-Layer protocol sites may be configured for single frequency F3 F1 F2 F2 F3 Site 2 F3 Site 1 F1 F3 Remote Programming F3 SCADA F2 12
Wireless IP Connection with SCADA Master Control Center Programming ToolBox IP Gateway IP Con. IP Network Ethernet 900 MHz 5.7 GHz Wireless IP Infrastructure IP Con. Programming STS IP Con. IP Con. IP Con. 13
Wireless GSM/GPRS Network Voice Site 1 Site 2 Micro Wave Back Bone Site 3 Voice Site 4 SCADA Voice 14
Combined PLC and I/Os with I/O Control With radio Customer Site STS ToolBox Wireless Network I/O Control PLC or IED with Native protocol Installed PLC or IED 15
SCADA Security Incident Trends Something Big Changes Here 28 18 * Projected 22* 20* 13 5 1 2 2 2 3 4 1 6 6 1982-1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Sept. 2005 Source: Eric Byres 16
Combined Set of Solutions May Help Physical Security Provide adequate security to remote sites Firewalls Protecting the corporate network Use of private data network Public networks are often vulnerable Use of complex protocol structure Need for specific analyzer IP Gateway Communications Security Combined Encryption and Authentication Multiple passwords across the system, etc. Master Control Center 17
Cost Saving Analysis 1/2 Calculate the overall Economic factors: Cost of lost potable water due to bursts and leakages Cost of electric energy during designated period Cost for repairs and replacement of equipment Cost travel to remote sites for periodic checkup Cost of system supervision and manual data collection Cost (without SCADA) Cost (with SCADA) Saving = -------------------------------------------------------------- (%) Cost (without SCADA) 18
Cost Saving Analysis 2/2 2500 2000 1500 1000 500 0 Without SCADA With SCADA Cost of lost potable water due to bursts and leakages Cost of electric energy during designated period Cost for repairs and replacement of equipment Cost travel to remote sites for periodic checkup Cost of manual data collection Total 19
System Programming Tasks With Simple Protocol With Layered Protocol Network Addressing Error Detection & Message Retry Diagnostics Data Security Built In Built In Built In Built In Main Application Main Application 20