what is scada?

Question

what is scada?

Answer 1

Look at

http://en.wikipedia.org/wiki/SCADA

Answer 2

SCADA is an acronym that stands for Supervisory Control and Data Acquisition. SCADA refers to a system that collects data from various sensors at a factory, plant or in other remote locations and then sends this data to a central computer which then manages and controls the data.



SCADA is a term that is used broadly to portray control and management solutions in a wide range of industries. Some of the industries where SCADA is used are Water Management Systems, Electric Power, Traffic Signals, Mass Transit Systems, Environmental Control Systems, and Manufacturing Systems.

Answer 3

SCADA stands for Supprvisory cantrol and data aquissition.

It gives us the visual display of the plant that how it is working and we can do online monitoring of any technical fault and can locate the fault.

Answer 4

It's a drug like pot.

Answer 5

SCADA:

SCADA is the abbreviation for Supervisory Control And Data Acquisition. It generally refers to an industrial control system which is meant to function across a wide area with an autonomous Remote Terminal Unit (RTU). The precise definition of SCADA has been muddied somewhat by newer telecommunications technology, enabling reliable, low latency, high speed communications over wide areas, and a tendency by popular media to mistakenly refer to all Industrial Control Systems as SCADA. Despite this confusion, a SCADA system is expected to have open loop controls (meaning that a human operator watches near real time data and issues commands). By comparison, a Distributed control system (DCS) is expected to have closed loop controls (meaning that real-time loop data is applied directly to an industrial controller without human intervention). These differences are primarily design philosophies, not mandates of definition.

The supervisory control system is a system that sends commands to a real-time control system to control a process that is external to the SCADA system (i.e. a computer, by itself, is not a SCADA system even though it controls its own power consumption and cooling). This implies that the system coordinates, but does not control processes in real time, as there is a separate or integrated real-time automated control system that can respond quickly enough to compensate for process changes within the time constants of the process. The process can be industrial, infrastructure or facility based as described below:

a. Industrial processes include those of manufacturing, production, power generation, fabrication, and refining, and may run in continuous, batch, repetitive, or discrete modes.

b. Infrastructure processes may be public or private, and include water treatment and distribution, wastewater collection and treatment, oil and gas pipelines, electrical power transmission and distribution, and large communication systems.

c. Facility processes occur both in public facilities and private ones, including buildings, airports, ships, and space stations. They monitor and control HVAC, access, and energy consumption.



Systems concepts:

SCADA systems, a branch of instrumentation engineering, include input-output signal hardware, controllers, human-machine interfacing ("HMI"), networks, communications, databases, and software.

The term SCADA usually refers to centralized systems which monitor and control entire sites, or complexes of systems spread out over large areas (on the scale of kilometers or miles). Most site control is performed automatically by remote terminal units ("RTUs") or by programmable logic controllers ("PLCs"). Host control functions are usually restricted to basic site overriding or supervisory level intervention. For example, a PLC may control the flow of cooling water through part of an industrial process, but the SCADA system may allow operators to change the set points for the flow, and enable alarm conditions, such as loss of flow and high temperature, to be displayed and recorded. The feedback control loop passes through the RTU or PLC, while the SCADA system monitors the overall performance of the loop.

Data acquisition begins at the RTU or PLC level and includes meter readings and equipment status reports that are communicated to SCADA as required. Data is then compiled and formatted in such a way that a control room operator using the HMI can make supervisory decisions to adjust or override normal RTU (PLC) controls. Data may also be fed to a Historian, often built on a commodity Database Management System, to allow trending and other analytical auditing.

SCADA systems typically implement a distributed database, commonly referred to as a tag database, which contains data elements called tags or points. A point represents a single input or output value monitored or controlled by the system. Points can be either "hard" or "soft". A hard point represents an actual input or output within the system, while a soft point results from logic and math operations applied to other points. (Most implementations conceptually remove the distinction by making every property a "soft" point expression, which may, in the simplest case, equal a single hard point.) Points are normally stored as value-timestamp pairs: a value, and the timestamp when it was recorded or calculated. A series of value-timestamp pairs gives the history of that point. It's also common to store additional metadata with tags, such as the path to a field device or PLC register, design time comments, and alarm information.



Human Machine Interface:

A Human-Machine Interface or HMI is the apparatus which presents process data to a human operator, and through which the human operator controls the process.

The HMI industry was essentially born out of a need for a standardized way to monitor and to control multiple remote controllers, PLCs and other control devices. While a PLC does provide automated, pre-programmed control over a process, they are usually distributed across a plant, making it difficult to gather data from them manually. Historically PLCs had no standardized way to present information to an operator. The SCADA system gathers information from the PLCs and other controllers via some form of network, and combines and formats the information. An HMI may also be linked to a database, to provide trending, diagnostic data, and management information such as scheduled maintenance procedures, logistic information, detailed schematics for a particular sensor or machine, and expert-system troubleshooting guides. Since about 1998, virtually all major PLC manufacturers have offered integrated HMI/SCADA systems, many of them using open and non-proprietary communications protocols. Numerous specialized third-party HMI/SCADA packages, offering built-in compatibility with most major PLCs, have also entered the market, allowing mechanical engineers, electrical engineers and technicians to configure HMIs themselves, without the need for a custom-made program written by a software developer.

SCADA is popular, due to its compatibility and reliability. It is used in small applications, like controlling the temperature of a room, to large applications, such as the control of nuclear power plants.



Hardware solutions:

SCADA solutions often have Distributed Control System (DCS) components. Use of "smart" RTUs or PLCs, which are capable of autonomously executing simple logic processes without involving the master computer, is increasing. A functional block programming language, IEC 61131-3, is frequently used to create programs which run on these RTUs and PLCs. Unlike a procedural language such as the C programming language or FORTRAN, IEC 61131-3 has minimal training requirements by virtue of resembling historic physical control arrays. This allows SCADA system engineers to perform both the design and implementation of a program to be executed on an RTU or PLC.



System components

The three components of a SCADA system are:

1. Multiple Remote Terminal Units (also known as RTUs or Outstations).

2. Master Station and HMI Computer(s).

3. Communication infrastructure



Remote Terminal Unit (RTU)

The RTU connects to physical equipment, and reads status data such as the open/closed status from a switch or a valve, reads measurements such as pressure, flow, voltage or current. By sending signals to equipment the RTU can control equipment, such as opening or closing a switch or a valve, or setting the speed of a pump.

The RTU can read digital status data or analog measurement data, and send out digital commands or analog setpoints.

An important part of most SCADA implementations are alarms. An alarm is a digital status point that has either the value NORMAL or ALARM. Alarms can be created in such a way that when their requirements are met, they are activated. An example of an alarm is the "fuel tank empty" light in a car. The SCADA operator's attention is drawn to the part of the system requiring attention by the alarm. Emails and text messages are often sent along with an alarm activation alerting managers along with the SCADA operator.

Quality SCADA RTUs have these characteristics:

a. Data Networking capability

b. Data Reliability

c. Data Security.



Master Station:

The term "Master Station" refers to the servers and software responsible for communicating with the field equipment (RTUs, PLCs, etc), and then to the HMI software running on workstations in the control room, or elsewhere. In smaller SCADA systems, the master station may be composed of a single PC. In larger SCADA systems, the master station may include multiple servers, distributed software applications, and disaster recovery sites. To increase the integrity of the system the multiple servers will often be configured in a dual-redundant or hot-standby formation providing continuous control and monitoring in the event of a server failure.

The SCADA system usually presents the information to the operating personnel graphically, in the form of a mimic diagram. This means that the operator can see a schematic representation of the plant being controlled. For example, a picture of a pump connected to a pipe can show the operator that the pump is running and how much fluid it is pumping through the pipe at the moment. The operator can then switch the pump off. The HMI software will show the flow rate of the fluid in the pipe decrease in real time. Mimic diagrams may consist of line graphics and schematic symbols to represent process elements, or may consist of digital photographs of the process equipment overlain with animated symbols.

The HMI package for the SCADA system typically includes a drawing program that the operators or system maintenance personnel use to change the way these points are represented in the interface. These represent

Answer 6

SCADA is the abbreviation for Supervisory Control And Data Acquisition. It generally refers to an industrial control system which is meant to function across a wide area with an autonomous Remote Terminal Unit (RTU). The precise definition of SCADA has been muddied somewhat by newer telecommunications technology, enabling reliable, low latency, high speed communications over wide areas, and a tendency by popular media to mistakenly refer to all Industrial Control Systems as SCADA. Despite this confusion, a SCADA system is expected to have open loop controls (meaning that a human operator watches near real time data and issues commands). By comparison, a Distributed control system (DCS) is expected to have closed loop controls (meaning that real-time loop data is applied directly to an industrial controller without human intervention). These differences are primarily design philosophies, not mandates of definition.



The supervisory control system is a system that sends commands to a real-time control system to control a process that is external to the SCADA system (i.e. a computer, by itself, is not a SCADA system even though it controls its own power consumption and cooling). This implies that the system coordinates, but does not control processes in real time, as there is a separate or integrated real-time automated control system that can respond quickly enough to compensate for process changes within the time constants of the process. The process can be industrial, infrastructure or facility based as described below:



Industrial processes include those of manufacturing, production, power generation, fabrication, and refining, and may run in continuous, batch, repetitive, or discrete modes.

Infrastructure processes may be public or private, and include water treatment and distribution, wastewater collection and treatment, oil and gas pipelines, electrical power transmission and distribution, and large communication systems.

Facility processes occur both in public facilities and private ones, including buildings, airports, ships, and space stations. They monitor and control HVAC, access, and energy consumption





SCADA systems, a branch of instrumentation engineering, include input-output signal hardware, controllers, human-machine interfacing ("HMI"), networks, communications, databases, and software.



The term SCADA usually refers to centralized systems which monitor and control entire sites, or complexes of systems spread out over large areas (on the scale of kilometers or miles). Most site control is performed automatically by remote terminal units ("RTUs") or by programmable logic controllers ("PLCs"). Host control functions are usually restricted to basic site overriding or supervisory level intervention. For example, a PLC may control the flow of cooling water through part of an industrial process, but the SCADA system may allow operators to change the set points for the flow, and enable alarm conditions, such as loss of flow and high temperature, to be displayed and recorded. The feedback control loop passes through the RTU or PLC, while the SCADA system monitors the overall performance of the loop.

SCADA solutions often have Distributed Control System (DCS) components. Use of "smart" RTUs or PLCs, which are capable of autonomously executing simple logic processes without involving the master computer, is increasing. A functional block programming language, IEC 61131-3, is frequently used to create programs which run on these RTUs and PLCs. Unlike a procedural language such as the C programming language or FORTRAN, IEC 61131-3 has minimal training requirements by virtue of resembling historic physical control arrays. This allows SCADA system engineers to perform both the design and implementation of a program to be executed on an RTU or PLC.

There is a trend for PLC and HMI/SCADA software to be more "mix-and-match". In the mid 1990s, the typical DAQ I/O manufacturer supplied equipment that communicated using proprietary protocols over a suitable-distance carrier like RS-485. End users who invested in a particular vendor's hardware solution often found themselves restricted to a limited choice of equipment when requirements changed (e.g. system expansions or performance improvement). To mitigate such problems, open communication protocols such as IEC870-5-101/104 and DNP 3.0 (serial and over IP) became increasingly popular among SCADA equipment manufacturers and solution providers alike. Open architecture SCADA systems enabled users to mix-and-match products from different vendors to develop solutions that were better than those that could be achieved when restricted to a single vendor's product offering.



Towards the late 1990s, the shift towards open communications continued with individual I/O manufacturers as well, who adopted open message structures such as Modicon MODBUS over RS-485. By 2000, most I/O makers offered completely open interfacing such as Modicon MODBUS over TCP/IP.



SCADA systems are coming in line with standard networking technologies. Ethernet and TCP/IP based protocols are replacing the older proprietary standards. Although certain characteristics of frame-based network communication technology (determinism, synchronization, protocol selection, environment suitability) have restricted the adoption of Ethernet in a few specialized applications, the vast majority of markets have accepted Ethernet networks for HMI/SCADA.



"Next generation" protocols such as OPC-UA, Wonderware's Archestra, and Rockwell Automation's FactoryTalk, take advantage of XML, web services, and other modern web technologies, making them more easily IT supportable.



With the emergence of software as a service in the broader software industry, a few vendors have begun offering application specific SCADA systems hosted on remote platforms over the Internet, for example, PumpView by MultiTrode. This removes the need to install and commission systems at the end-user's facility and takes advantage of security features already available in Internet technology, VPNs and SSL. Some concerns include security,[1] Internet connection reliability, and latency.



SCADA systems are becoming increasingly ubiquitous. Thin clients, web portals, and web based products are gaining popularity with most major vendors. The increased convenience of end users viewing their processes remotely introduces security considerations.



The move from proprietary technologies to more standardized and open solutions together with the increased number of connections between SCADA systems and office networks and the Internet has made them more vulnerable to attacks. Consequently, the security of SCADA-based systems has come into question as they are increasingly seen as extremely vulnerable to cyberwarfare/cyberterrorism attacks.[2][3]



In particular, security researchers are concerned about:



the lack of concern about security and authentication in the design, deployment and operation of existing SCADA networks

the mistaken belief that SCADA systems have the benefit of security through obscurity through the use of specialized protocols and proprietary interfaces

the mistaken belief that SCADA networks are secure because they are purportedly physically secured

the mistaken belief that SCADA networks are secure because they are supposedly disconnected from the Internet

Due to the mission-critical nature of a large number of SCADA systems, such attacks could, in a worst case scenario, cause massive financial losses through loss of data or actual physical destruction, misuse or theft, even loss of life, either directly or indirectly. Whether such concerns will cause a move away from the use of existing SCADA systems for mission-critical applications towards more secure architectures and configurations remains to be seen, given that at least some influential people in corporate and governmental circles believe that the benefits and lower initial costs of SCADA based systems still outweigh potential costs and risks.[citation needed] Recently, multiple security vendors, such as Byres Security, Inc., Industrial Defender Inc., Check Point and Innominate, and N-Dimension Solutions have begun to address these risks by developing lines of specialized industrial firewall and VPN solutions for TCP/IP-based SCADA networks.



Also, the ISA Security Compliance Institute (ISCI) is emerging to formalize SCADA security testing starting as soon as 2009. ISCI is conceptually similar to private testing and certification that has been performed by vendors since 2007, such as the Achilles certification program from Wurldtech Security Technologies, Inc. and MUSIC certification from Mu Security, Inc. Eventually, standards being defined by ISA SP99 WG4 will supersede these initial industry consortia efforts, but probably not before 2011.