COMPARISON of .NET or ACTIVE X controls vs. OPC   .NET or ACTIVE X: • This concept was introduced in 1991 and the ActiveX name was coined in early 1996. • In-Process server integrated into one single application. • Extremely light weight. • A very solid foundation to begin with. • Almost every Microsoft product supports it. • Thousands of companies support it world-wide. • Extremely fast and low resource consumer. • Typically run-time licenses are free. • Several options available to build client-server or n-tier applications. • Only one application needed. • Natively based on COM & DCOM   Additional issues for .NET • Introduced early 2003. • Native Support for COM & DCOM withdrawn. Use layers to support COM & DCOM. • Basis for all long-term software technology infrastructure.   OPC: • Introduced in 1997. • Extremely heavy, needs a very souped up machine. • The specification has been a moving target. • No Microsoft product has native support for OPC except VC++. You must use automation layer as an interface. • Very few companies support OPC. • Slow and heavy on resources. • Based on COM & DCOM. • Setup is very complicated unless using on the same machine & from the same vendor. • Must pay for each node. • Must run multiple applications.     For More Information on any of our products please contact us