involved in the complexities of plant floor equipment integration. Connectivity becomes the responsibility of the system integrator. EATM (Enterprise Transaction Modules) – These devices have the ability to communicate directly with plant floor equipment and will transact data with the business system in methods best supported by the business system. Again, this can be through a staging table, Web Services, or through system specific business system APIs. The benefit of an EATM is that it offers a complete, off the shelf solution, minimizing long term costs and customization. Custom Integrated Solutions – Many system integrators designs offer custom crafted solutions, created on a per instance basis to meet site and system requirements. There are a wide variety of communications drivers available for plant floor equipment and there are separate products that have the ability to log data to relational database tables. Standards exist within the industry to support interoperability between software products, the most widely known being OPC, managed by the OPC Foundation. Custom Integrated Solutions typically run on workstation or server class computers. These systems tend to have the highest level of initial integration cost, and can have a higher long term cost in terms on maintenance and reliability. Long term costs can be minimized through careful system testing and thorough documentation. External links www.opcfoundation.org ARC Advisory Group Comments on Enterprise Appliance Transaction Modules Industrial automation Manufacturing Control engineering