In the world of industrial automation, the Open Platform Communications (OPC) protocol is key. It helps devices, control systems, and applications talk to each other smoothly. This makes it easier for products from different makers to work together, making industrial control systems more efficient1.
OPC has two main types: OPC Classic and OPC Unified Architecture (UA). OPC Classic started in 1996, using Microsoft Windows and COM/DCOM for data sharing1. Then, in 2006, OPC UA came along. It combined the best of OPC Classic into a new, flexible, and secure way to share data1.
Key Takeaways
- OPC Classic, established in 1996, was based on Microsoft Windows technology and used COM/DCOM for data exchange.
- OPC Unified Architecture (UA), introduced in 2006, is the successor to OPC Classic, offering platform independence and stronger security features.
- OPC UA supports multiple transport protocols, including TCP, HTTPS, and WebSocket, enabling its use in IIoT, smart manufacturing, and remote equipment monitoring.
- OPC DA is primarily used for accessing and exchanging real-time data, while OPC UA has a more comprehensive information model.
- Factors to consider when choosing between OPC UA and OPC DA include system platform, data model complexity, security requirements, scalability, project budget, and technical team capabilities.
Introduction to OPC Protocols
What is OPC?
OPC stands for “Open Platform Communications”. It’s a key standard in industrial automation2. It helps different software and hardware talk to each other, making communication between devices and systems smooth2. Before OPC, devices in automation didn’t have a common way to connect, causing confusion and high costs2.
The Evolution of OPC Standards
The first OPC standard came out in 1996, called OPC Classic2. It used Microsoft Windows and COM/DCOM to let software parts talk to each other. Later, in 2006, OPC UA was introduced to fix some issues with OPC Classic2. OPC UA is now a flexible, independent, and service-focused framework3. It’s more secure and can handle more data than OPC Classic3.
Now, both OPC Classic and OPC UA are big names, with millions of users worldwide2. OPC Gateway apps also help share data between OPC UA and OPC DA2. Companies like Software Toolbox offer tools that work with both OPC Classic and OPC UA2.
“OPC technology enables the exchange of data between controllers and SCADA systems.”4
Unpacking OPC DA
What is OPC DA?
OPC Data Access (OPC DA) is a key protocol standard by the OPC Foundation. It’s mainly used for real-time data access in industrial automation systems5. It uses Microsoft’s COM/DCOM tech for a standard way to communicate. This lets many clients access data on a server at the same time5.
This client-server setup is common in fields like manufacturing, process control, and energy management5.
Pros and Cons of OPC DA
OPC DA is well-established and easy to use, making it a top choice for many5. But, it has some downsides too. It relies on Windows, lacks strong security, and has a basic data model6.
Even though many vendors support OPC UA, some systems might not be ready for it. This could be due to outdated products, devices using OPC XML-DA, or new systems lacking OPC UA5. To fix this, tools like DataHub OPC Gateway offer ways to switch to OPC UA while keeping old investments5.
Companies often need real-time links between OT, IoT, and ERP systems. This need has led to solutions like OPC Router. It supports many protocols, helping to connect ERP systems with OPC UA5.
Using OPC UA for historical data is key for smart decision-making. Flow Software’s analytics platform connects to OPC UA data for better decisions5.
While OPC DA is reliable, new industry needs and tech have pushed for OPC UA’s growth. Choosing between OPC DA and OPC UA depends on a company’s specific needs.
“OPC Data Client significantly lowers the complexity for developers in OPC client development projects.”7
The OPC Data Client, made by Software Toolbox, has been solving OPC issues since 19967. It offers a connection-less interface, making OPC tasks simpler. This means less code for handling connections and more efficient operations7.
The toolkit also lets you work on multiple elements at once and keeps data in memory to avoid extra OPC reads. It uses async calls to keep threads from getting blocked7.
| Pros of OPC DA | Cons of OPC DA |
|---|---|
| Mature technology Wide application Ease of implementation and deployment | Dependency on Windows platform Lack of security mechanisms Simple data model |
Understanding OPC UA
OPC Unified Architecture (OPC UA) is a new protocol standard by the OPC Foundation. It was created to fix the issues of its older version, OPC DA8. Introduced in the mid-2000s, OPC UA uses TCP/IP for sharing data in real-time. It offers better security, reliability, and efficiency8.
What is OPC UA?
OPC UA is built on a service-oriented architecture (SOA). It’s a secure, scalable way to share data in industrial automation and IIoT9. Unlike OPC Classic, it’s based on TCP/IP, ensuring secure data transfer with encryption and checks8.
It supports complex data types and lets manufacturers create custom data models for their needs9. Its flexible design works well with many devices, from small PLCs to big HMI stations and SCADA systems8.
Pros and Cons of OPC UA
OPC UA’s main benefits are its independence from platforms, strong security, and detailed data modeling9. It works with many operating systems, like Windows, macOS, Android, and Linux, making it versatile for industrial automation and IIoT9.
But, it can be more complex and costly to develop and implement than OPC DA10. It also requires specialized knowledge, which might be a hurdle for some companies9.
Despite these challenges, OPC UA is widely used in fields like oil and gas, agriculture, and smart cities9. It’s set to be key in connecting devices and systems as industrial automation grows8.
“OPC UA is a crucial enabler for Industry 4.0 and the Industrial Internet of Things, providing the necessary data integration and communication solutions for the future of manufacturing.”
Key Differences Between OPC DA and OPC UA
Industrial communication has changed a lot, showing big differences between OPC DA (Data Access) and OPC UA (Unified Architecture). These standards are different in many ways, like how they find services, use namespaces, control access, and handle events and data1.
OPC DA started in 1996 and depends on Microsoft Windows, using COM/DCOM for sharing data1. OPC UA came later, in 2006, and is better than OPC Classic in security and size, not tied to any platform1. It uses TCP, HTTPS, and WebSocket for data transfer, making it great for IIoT and smart manufacturing1.
OPC UA has stronger security with things like authentication and encrypted data, fixing some of OPC DA’s issues1. It also works on many operating systems, unlike OPC DA which only works on Windows1.
| Feature | OPC DA | OPC UA |
|---|---|---|
| Security | Limited security features | Strong security with authentication, authorization, and encryption |
| Cross-platform Support | Windows-only | Cross-platform compatibility |
| Data Modeling | Older data modeling capabilities | Advanced data modeling features |
| Communication | Relies on DCOM, dependent on Windows OS | Platform-independent communication |
| Data Exchange | Uses VQT (Value Quantity Time) | Offers extensive properties sharing between client and server |
| Advanced Features | Lacks historical events, alarms, and robust security | Supports historical events, multiple hierarchies, methods, and programs |
OPC UA has more advanced features than OPC DA, offering better flexibility, security, and growth for industrial automation and IIoT1. Its ability to work on different platforms, better security, and advanced data handling make it a better choice for the future1.
“OPC UA makes it easy to integrate data from machines to higher-level systems in smart factories.”1
OPC DA vs OPC UA: A Comparative Analysis
The debate between OPC DA and OPC UA in industrial automation is ongoing. Since 1996, OPC DA has been the go-to protocol11. But OPC UA has changed how systems talk to each other and share data.
OPC DA uses Microsoft’s COM/DCOM and works mainly on Windows. OPC UA, on the other hand, uses a service-oriented architecture and works on many platforms11. This makes OPC UA more flexible and able to grow with different systems11.
OPC UA is better at handling data modeling than OPC DA11. It offers more ways to model devices and processes. This leads to easier server address spaces and better handling of complex systems11.
OPC UA is also stronger in security. It has built-in security features to protect against cyber threats11. OPC DA, however, has been seen as less secure, making OPC UA a better choice for today’s connected world11.
Choosing between OPC DA and OPC UA depends on many factors. These include the system’s needs, data modeling, security, and future plans11. Companies need to look at both protocols’ strengths and weaknesses to pick the right one for them.
OPC UA has become a strong contender to OPC DA’s long-standing position11. Its benefits, like being platform-independent, more secure, and better at data modeling, are driving its adoption12.
In conclusion, OPC UA has clear advantages over OPC DA, especially in being more independent, secure, and detailed in data modeling1112. As industries move towards Industry 4.0, choosing between these protocols will be key for automation experts.
Factors to Consider When Choosing Between OPC UA and OPC DA
Choosing between OPC UA and OPC DA depends on several key factors. You need to think about your system’s platform and how it needs to work with other systems. Also, consider the complexity of your data and what your system needs to do. Think about how important security and reliability are for you. Also, consider if you need your system to grow and change in the future.
Think about your budget and timeline for the project. And don’t forget about your team’s skills and what they can handle.
OPC UA works well on many platforms, including Linux, Mac, and Windows13. This makes it great for projects that need to work across different systems. It also has strong security, like encryption, which is key for IIoT and Industry 4.0 projects14.
OPC UA is better for complex data needs because it lets you use flexible data types and structures13. It’s perfect for applications that need to handle a lot of data. It’s also designed to grow and support more information models, making it a smart choice for the future1514.
But, OPC DA might still be right for some older systems or projects on a tight budget. It uses COM technology and is well-known among SCADA vendors15. The OPC Foundation also offers tools to check if different systems work well together, ensuring they’re compatible and reliable15.
So, deciding between OPC UA and OPC DA should be based on what your system really needs. Think about your budget and your team’s skills. OPC UA is a good choice for projects looking to the future because of its strong features and flexibility. But, OPC DA could still be the better option for some older systems or projects that are watching their budget closely.
“OPC UA is the next evolution of classic OPC with abstract data model and platform independence.”15
Can OPC UA Completely Replace OPC DA?
OPC UA is an improved version of OPC DA, but it can’t fully replace it in all cases, especially for older systems16. OPC DA has been around since 1995, making it nearly 30 years old16. Today, both OPC DA and OPC UA are needed, as OPC UA can’t replace OPC DA everywhere17. The content often talks about both protocols and compares them17.
The UaGateway helps connect OPC DA and OPC UA, but it’s just a wrapper18. The Support Team says you can’t fully rename nodes with UaGateway18. This shows it’s hard to switch from OPC DA to OPC UA, especially for older systems that need to keep their setup18.
OPC UA uses a different address format than OPC DA, which can cause issues18. The Support Team suggests using a default namespace to match UA NodeIds with COM ItemIds18. This means you need to be careful when using both OPC DA and OPC UA together18.
In conclusion, OPC UA is better than OPC DA in many ways, but it can’t replace it everywhere, especially for older systems17. Both OPC DA and OPC UA are important for today’s industrial automation needs17.
| Feature | OPC DA | OPC UA |
|---|---|---|
| Security | Encryption is not a standard option | Enforces user authentication and supports multiple mechanisms like Username and password, Digital certificate and Kerberos ticket |
| Confidentiality and Integrity | Not a default feature | Offered as a default feature |
| Application Authentication | Complex process | Simplified process |
| User Identification | Less effective across different environments | More effective across different environments |
| Server Auditability | No log file storage for events tracking | Allows log file storage for events tracking |
| Server Availability | No standard recommendations for backup and redundancy | Recommends implementing backup and redundancy servers |
“OPC UA was developed to address security concerns and platform independence, while OPC DA (Data Access) interface remains the most widely used and implemented in industrial devices.”16
Is OPC UA Difficult to Implement?
The OPC UA protocol might look complex, but there are now many tools and frameworks that make it easier19. Many vendors also offer solutions based on OPC UA, making it easier for professionals in industrial automation19.
OPC UA offers better security than OPC Classic19. It combines different specifications into one with an Object-based model19. This makes it great for working with systems on Linux and other non-Microsoft platforms19.
New OPC UA Client devices might also support OPC Classic to help move from Classic to UA19. Siemens, a big PLC maker, supports OPC UA and sees it as the future for easy communication19.
IT departments might push for OPC UA because of its strong security focus, especially after recent cyber attacks19. OPC UA is starting to get more popular in the US19.
To sum up, OPC UA might seem tough at first, but with the tools and benefits it offers, it’s becoming a good choice for those in industrial automation1920.
OPC DA vs OPC UA: Security Features
The OPC standard started in 1996 and quickly became a key part of the industry in just two years21. OPC DA is widely used for sending real-time data from PLCs to HMI/SCADA systems21. But, it has limited security, depending on Windows DCOM, which can be hard to manage for remote access22. Users often have to turn off all security or use special OPC programs to connect securely.
OPC UA, on the other hand, has strong security with features like authentication, authorization, and encrypted data22. It uses standard security like X.509 certificates for better control over who can access and what they can do12. OPC UA was made by the OPC Foundation to fix the old OPC standard’s issues from the mid-1990s12. It’s perfect for Industry 4.0 because it works well with old and new systems12.
OPC UA has much better security than OPC DA, with stronger checks for who can access and what they can do22. Its secure authentication, authorization, and encryption make it a safer choice for industrial automation12.
Data Modeling Capabilities: OPC DA vs OPC UA
OPC DA and OPC UA have different ways of handling data modeling. OPC DA uses a simple tree-like structure to organize industrial data23. But OPC UA goes further, offering a more detailed and flexible way to model data23.
OPC UA stands out by supporting complex data types and detailed descriptions23. This means it can capture the complex nature of industrial data and business rules23. It’s ideal for complex applications, letting users share the details of their systems clearly23.
OPC UA’s model is also designed to grow and change, letting companies create their own data models that fit the OPC system23. This flexibility makes OPC UA great for meeting the varied needs of modern industrial data23.
OPC DA, on the other hand, focuses mainly on a simple tree structure for data23. While it works for some, the complexity of today’s systems often requires OPC UA’s deeper data modeling23.
In conclusion, OPC UA outshines OPC DA in data modeling, offering a deeper and more flexible way to handle industrial data and logic23. This makes OPC UA the top choice for complex data modeling needs, helping users to better understand and improve their processes23.
| Feature | OPC DA | OPC UA |
|---|---|---|
| Data Modeling | Basic hierarchical representation | Richer data model with support for complex data types and semantic descriptions |
| Extensibility | Limited vendor-specific extensions | Allows vendors to build their own data information models within the OPC ecosystem |
| Suitability for Sophisticated Applications | Limited capability for complex data modeling requirements | Better suited for applications with advanced data modeling needs |
“OPC UA’s data model is designed to be extensible, enabling vendors to build their own data information models that fit seamlessly within the OPC ecosystem.”
Case Study: Industrial Gateway Supporting OPC Protocols
Technology like NeuronEX is changing the industrial world. It helps with data integration and edge intelligence. NeuronEX is a software that collects data from equipment and analyzes it at the edge24. It supports many industrial protocols, including OPC UA24. The NeuronEX OPC UA plugin can connect to OPC UA servers or devices24.
NeuronEX doesn’t support OPC DA directly, but you can use NeuOPC to convert OPC DA data to OPC UA. This lets users use OPC UA’s benefits while still connecting to old OPC DA systems24. This makes the industrial gateway better, giving access to more data sources and improving edge intelligence for better decisions.
| Feature | OPC DA | OPC UA |
|---|---|---|
| Scalability | Limited to hundreds of clients and thousands of data points | 24OPC UA clients may easily connect to hundreds of servers and dozens of thousands of nodes24. |
| Communication Model | 24MQTT is a one-way communication protocol24. | 24OPC UA is a request-response two-way communication method24. |
| Implementation Complexity | Relatively simpler to implement | 24Programming an OPC UA client or server takes a few weeks to implement using the commercial SDK24. |
Using NeuronEX with OPC UA helps industrial companies use edge intelligence, data acquisition, and connect to IIoT devices easily. This approach lets companies use their industrial data fully, making better decisions and improving operations at the edge.
As technology advances, NeuronEX will be key in making industrial gateways central to the IIoT revolution. It connects old systems with modern OPC UA tech, offering a smooth way for companies to use edge computing and data for better decisions2425.
Conclusion
The move from OPC DA to OPC UA marks a big step forward in industrial communication. OPC DA was key for real-time data sharing26. But OPC UA is now the top choice for its strong and forward-thinking features.
OPC UA stands out with its ability to work on any platform, strong security27, and advanced data handling26. It’s the go-to for new projects and those with changing needs. The27 protocol uses strong security and is key for safe, reliable device communication27. It also works well with both high-end and basic devices27, making it perfect for Industry 4.0 and IoT.
Even though OPC DA is still used in some old systems, OPC UA’s benefits like26 working on any platform, growing capacity, and26 better data sharing make it the top pick for keeping up with the future. As industries grow, OPC UA is being widely used in fields like manufacturing, energy, and transport. This shows its importance as a key standard for today’s industrial world.
FAQ
What is OPC?
OPC (Open Platform Communications) is a key standard in industrial automation. It helps devices and systems from different makers talk to each other. This makes industrial control systems work better together.
What are the different OPC standards?
OPC has two main standards: Classic and Unified Architecture. Classic started in 1996 and uses Microsoft Windows technology. It lets devices share data. OPC Unified Architecture (UA) came out in 2006. It makes things work together better and is more flexible.
What is OPC DA?
OPC DA (Data Access) is a way to share real-time data. It was created by the OPC Foundation. It uses Microsoft’s COM/DCOM technology for communication.
What are the pros and cons of OPC DA?
OPC DA is well-known and easy to use. It works well in many places. But, it only works on Windows, lacks security, and has a simple data model.
What is OPC UA?
OPC UA is a newer way to share data, made by the OPC Foundation. It uses a service-oriented architecture. This makes it secure, flexible, and works on any platform.
What are the pros and cons of OPC UA?
OPC UA is great because it’s platform-independent and secure. It also has a detailed data model. But, it can be complex, which makes it more expensive to use.
What are the key differences between OPC DA and OPC UA?
OPC DA and OPC UA are very different. They have different ways of finding services, controlling access, and sending data. OPC UA is more advanced, offering better security and flexibility.
When should I choose OPC DA over OPC UA?
Choose between OPC DA and OPC UA based on your system’s needs. If you need something for the future, go with OPC UA. But, if you’re working with older systems or watching your budget, OPC DA might be better.
Can OPC UA completely replace OPC DA?
OPC UA is better than OPC DA in many ways. But, sometimes OPC DA is still needed, especially for older systems. Both can work together, as OPC UA can’t replace OPC DA everywhere.
Is OPC UA difficult to implement?
OPC UA can seem complex, but there are many tools and frameworks to help. Many vendors also offer solutions based on OPC UA, making it easier for professionals to use.
How do OPC DA and OPC UA differ in terms of security features?
OPC DA’s security is limited, relying on Windows DCOM which can be hard to manage. OPC UA, on the other hand, has strong security with things like encryption and secure authentication.
How do OPC DA and OPC UA differ in data modeling capabilities?
OPC DA is basic in data modeling. OPC UA is more advanced, handling complex data and descriptions. This makes OPC UA better for detailed data needs.
How does an industrial gateway support OPC protocols?
NeuronEX is a gateway software for collecting and analyzing equipment data. It supports many protocols, including OPC UA. You can use the NeuronEX OPC UA plugin to connect to OPC UA servers or devices. For OPC DA, you can use NeuOPC to convert the data for NeuronEX.