Middleware is one of those things that requires understanding and integration beyond the RFID network. No matter how good you are as a physicist or RF engineer, without a proper software background you are unlikely to be able to comprehend the subtleties of middleware beyond the basics. CompTIA understands this and consequently does not have extensive coverage of the middleware component of RFID. What they want you to know are just the basics. So in this last section I will take you through the components of middleware, what it does, and what is important to the end user.
Middleware bridges the gap between raw data from a tag to the business applications that create actionable data. An RFID reader at its basic level has no intelligence imbedded on it. As far as a reader is concerned, there is no difference between six million reads and one read. However, to a business application there is a huge difference. This is why data filtering is the key aspect of RFID middleware.
To give you an example of how middleware can help out, imagine it's 9:15 AM and time for a coffee break. The forklift driver who is unloading a truck stops within the interrogation zone for his break. The reader on the portal is going to read continuously, perhaps every 300th of a second. That's 3.3 reads per second, and if the forklift sits there for 15 minutes, the same tags are going to be read almost 3,000 times. The business application needs to know only whether the tag came in the dock door. In other words, did the facility receive the case? So that requires only one read. Reading the tag data is not an extensive burden. However, if someplace is receiving hundreds of thousands of tagged items each day, then the difference between reading something once and sending that data to a central data base, and reading it 3,000 times and sending all that data to the same place, would be material. The middleware filters all those unnecessary reads and smooths out the data that is sent up to the higher level applications.
Middleware can also control a reader and devices attached to the readers such as light stacks and motion detectors. This capability is not inherent on all middleware packages. However, the more-mature programs, which can also control barcode readers and other handheld devices, usually have advanced functionality built in.
RFID middleware selection requires several steps. The critical first step is to finalize the detailed design and business process steps. The detailed design will include what happens at what particular steps in the process when RFID is introduced into a system. That is why the swim lane diagrams in Chapter 3, "Site Analysis," are so important. The design process finalizes screen flows for the middleware design-in other words, what happens at a particular step in the process if something is read by an RFID reader, and what happens if it is not read and is supposed to be. This set of activities then proceeds to configuring the work flows, rules, screens, data model, and integration. After the system is fully configured, it is unit tested in a controlled environment prior to full system testing on-site. It is important to conduct the controlled testing off-site first because basic functionality can be evaluated and bugs fixed prior to on-site installation. This saves time in troubleshooting and reduces the installation time on-site. If the system is being deployed across multiple facilities and supports multiple work flows, each facility will be system tested in turn and then the entire network will be tested as an enterprise.
There are more than a dozen middleware applications that are commercially available in 2006, and none of them are ready for deployment "out of the box." Even the more-mature middleware components require custom integration with a client's systems to make it truly effective. I also think the middleware market for RFID is going to disappear over the coming years-the functionality is not that complex from a software perspective. This is why reader manufacturers are putting more intelligence on their readers, and software vendors such as Oracle and Microsoft are putting RFID functionality in their applications. This pressure from the top (application) and pressure from the bottom (readers) will squeeze specialized middleware applications out of the market.