is the industrial standard created by a consortium of manufacturers supported by Microsoft. Most of the companies that offer distributed control equipment, instruments, databases, etc. to their clients, have the key to connect with the control network through the OPC interface

this protocol, sets a clear division between hardware manufacturers and controllers developers. The technology provides a mechanism to collect data from different sources and to transfer these data to any application of the client, regardless of the type of the equipment used. This process allows developers to focus on the performance and optimization of data.

is an international organization located in Boca Raton, Florida, the USA, responsible for the development of the OPC standards, support, and promotion. This organization has more than 250 members, including leading growth companies related to the development of programs for the control, visualization, and programming, as well as other applications for control processes, for example, Honeywell, Fisher - Rosemount, Siemens, Wonderware, Intellution, among others. Microsoft, Inc. is also a member of the OPC Foundation, it participates in the development of new specifications.

This standard, is based on the client-server communication diagram. This architecture does not limit the connection of many clients to the same server, on the contrary, this standard allows that a client connects to different servers.

this standard, can be used for the data interchange in the industrial information systems. There are servers that communicate with automated control systems, built in the PLC (PLC – Programmable Logic Controllers). They are designed based on the communication protocol (for example AS511, RK512, S -bus, Modbus, DF1, etc.) and the connected equipment (for example, PLC), which are automatically recognized.

this part of the standard, creates an object and a special communication channel (thread). This action protects the data interchange against the influence of other OPC-clients and improves the performance of the OPC-server.

this part of the standard do not support OPC interface, and they are not COM objects (Component Object Model). It is an internal object of the OPC-server, containing the important information about the OPC–clients requests. For example, the type of data used to load values, or the status (active or passive) of the requested values, etc.

this part of the standard sends data about the batch process and supervises its application. OPC Batch is another OPC specification widely used in automation. It is used for processes that require batchers in manufacturing; it monitors proportions (laboratory systems, batching, weighing systems, etc.). It is important to mention that each OPC Batch (client) is also an OPC Data Access 2.0 server (client). In other words, the OPC Batch server (client) also includes the OPC Data Access 2.0 specification and some additional interfaces (for example, browsing variables)

it is a flexible and easy-to-use interface for the data interchange through OPC, using XML (Extensible Markup Language) in the Internet / Intranet applications. The XML functions allow the recording of data files in format .xml, and send them through the Internet.