Introduction | OPC Technology | OPC Specifications
OPC Data Access Specification | DCOM Configuration | References

OPC Technology

Communication is always a very important task. In industries, it is not different. Automation control needs to swap information between a large amount of devices.

With the fast development of communication systems, each manufacturer created it's own device driver, and it's own protocol specification. This action turned impossible communication between all devices due incompatible protocols.

The SCADA (Supervisory Controle And Data Acquisition) systems were created to solve these problems. These systems have various drivers to manage the communication between all devices from different manufacturers.

These systems were used since the creation of OPC (OLE for Process Control) standard. OPC tries to create a standard communication between all applications systems turning undispensable the driver use. OPC works only above the seventh layer of the ISO/OSI model.

The above image shows the complete communication process. OPC defines only methods and data type that can be used between servers and clients communication.

All of OPC specifications are made by OPC Foundation. This page has an explanation about OPC.

A complete reference of the ISO/OSI model can be obtained at Wikipedia.