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The Chinese Year of the Rat also spells launch time for the long awaited OPC-UA specification, and according to Eric Murphy, the furry rodent actually has a lot in common with the latest version of the automation system interface standard.
According to Chinese astrology the future can be divined from one’s birth date. Although work on the OPC-UA (Unified Architecture) specifications began several years ago and several parts have been released, 2008 can be considered the year OPC-UA is truly born: all parts of the specification will be released, coding milestones reached and preliminary productsdeveloped.
But what does ancient philosophy say the future holds for OPC-UA delivered in the Year of the Rat?
1. Rats are leaders and pacesetters and usually have extraordinary success in life.
OPC is the successful leader in meeting the needs many companies strive for: interoperability and integration of their information systems.
Interoperability means applications and systems have the ability to share information and exchange services based on standards and cooperate in processes using the information and services. In other words, applications acquire, share and understand data and use information in a standard way.
Companies have different reasons for wanting standard system interoperability. Those working with reduced inventories require increased response times. Those who need better planning and decision-making require access to accurate and current information.
Those looking for improved consistency and quality require more automated business processes. Those facing increased customer-service and compliancereporting demands require access to additional information.
All these reasons point to improved interoperability and OPC is leading the way.
2. Rats are achievers who establish roots early in order to make a secure future
The term OPC has evolved in scope over time. Most users are familiar with the classic OPC standards that standardize information exchange for process data. These specifications are based on Microsoft’s COM/DCOM technology, and represent many thousands of OPC-based products and installations, across industries and around the globe. More recently, “OPC” has come to mean the OPC unified architecture (UA) standard, and the functionality it represents.
OPC-UA is based on a platform-independent, service-based architecture and has been designed to extend OPC to address the needs of enterprise-level interoperability. Members of the OPC early adopters implementation group include many of the major control systems and OPC product suppliers. This strong backing reflects the commitment to ensuring that OPC-UA enjoys the same level of success and adoption as the current OPC specifications.
OPC-UA is targeted as the architecture of the near future, but what is it about OPC today that caused pacesetter companies to make it their connectivity standard?
3. Rats are highly organized, meticulous, systematic and dependable.
Regardless of what business a company is in, market dynamics are demanding faster response times and more efficient decision-making. These demands mean the need for better and faster data, from more sources and delivered to many destinations.
To achieve the benefits of flexible, scalable and interoperable systems, without high integration costs and time, the solution must also be standardized across multiple vendors, systems and products. That is the challenge OPC successfully addresses, and is the foundation OPC-UA is built upon.
OPC provides a functional interface for reading and writing data in an efficient and deterministic way. Separate specifications address different data semantics, including real-time and historical data, alarm and event information, and batch data. The interfaces are comprehensive enough to provide the functionality that users require, yet simple and practical to implement, which results in wide vendor acceptance. Proper adherence to the OPC standards is aided by the OPC Foundation Certification process, which includes compliance tools, interoperability sessions and third-party certification.
These factors have led to creating fast, flexible and reliable connectivity solutions that businesses require.
4. Rats are energetic and versatile and easily adapt to various environments.
If OPC offers so much in the way of connectivity, what does the future hold with the adoption of OPC-UA?
The primary purpose of classic OPC was to solve the integration problem between devices and PC-based client applications. The automation industry’s desire for connectivity standardization has led to OPC being used in a wider range of applications than was originally considered. The scope now extends to enterprise-level interoperability, which includes applications from the field level all the way to the realm of enterprise report planning software, across multiple hardware platforms, and in globally diverse installations.
As technology and market requirements change, so must the interoperability standards. Therefore, OPC-UA extends the scope of the classic OPC specifications. The single OPC-UA architecture encompasses and unifies the functional data format for real-time, historical, event-based and batch information. The OPC-UA specifications also go farther in setting standards for application security, reliability, audit tracking and information management. These are key components for interoperable enterprise architectures.
In addition the OPC Foundation has been actively collaborating and partnering with industry standards bodies such as ISA, EDDL, FDT, MIMOSA, OAGi and others. The participation of members from OPC and collaboration organizations in respective standards development ensures OPC-UA delivers a communications infrastructure that meets the needs of the industrial enterprise.
For instance, the FDT Group and ECT (EDDL Cooperation Team) announced they are working together to define a common OPC-UA Information Model for device descriptions. An OPCUA Working group has also recently formed to develop support for Analyzer Devices Integration. These show the level of long term commitment that is forming.
5. Rats know exactly where to find solutions and can take care of problems.
Enterprise solutions of the future must be fully “Web-enabled”. The OPC-UA specifications are implemented on a service-based architecture that leverages existing standards such as XML, SOAP and WS initiatives. Services-based implementations are supported by Microsoft as well as many other operating systems. This means OPCUA will be available on a wide range of platforms, including embedded operating systems. This promotes the power of standard-based connectivity across more layers of the enterprise.
A service-based model also allows OPCUA to leverage standard security aspects such as authentication, encryption, data integrity and auditing. OPC-UA provides standard security features at multiple levels of the specification. These are important features for companies in the face of increasing security requirements.
6. Rats are among the most fit of all the Animal signs to survive most any situation.
In addition to extending, unifying and allowing backward compatibility with existing OPC products, OPC-UA offers a rich information model to better transform the data into information. OPC-UA allows access to multiple data sources and formats, and in addition, supports reference semantics so client applications can discover and understand the information they are collecting.
These capabilities provide the foundation for powerful OPC-UA client applications that are being developed by vendors. The same flexible, secure interfaces could be available on a smart transmitter, the control system operator station, the historian, maintenance database and the manufacturing execution system; a single interoperable data route from the field to enterprise levels.
7. Being the First Sign, Rats are leaders, pioneers and conquerors.
OPC has established firm roots with its successful history of standardizing integration for the automation industry. What the future holds for OPC-UA is yet to been seen as the specification stabilizes, products are delivered and adoption progresses. But when you consider the features OPCUA possesses, the support of multiple vendors and the collaboration demonstrated by other industry bodies, then its future as the nextgeneration of enterprise interoperability is auspicious indeed.
What is OPC?
OPC is designed to bridge process control hardware and software applications. It is an open standard that permits a consistent method of accessing field data from plant floor devices. This method remains the same regardless of the type and source of data. OPC-UA (Unified Architecture) encompasses a new set of specifications not based on Microsoft COM that will provide standards-based, crossplatform capability.
OPC servers provide a method for many different software packages to access data from a process control device, such as a PLC or DCS. Traditionally, any time a package needed access data from a device, a custom interface, or driver, had to be written. The purpose of OPC is to define a common interface that is written once and then reused by any business, SCADA, HMI, or custom software packages.
Once an OPC server is written for a particular device, it can be reused by any application that is able to act as an OPC client. OPC technology permits a standard for realtime information exchange between software applications and process hardware to be defined.
Eric Murphy, Advanced Architecture System Design Engineer, MatrikonOPC, is an active member of the OPC Unified Architecture (UA) Working Group. Visit Eric at: blog.matrikonopc.com.
