Issue #11 | January 13, 2005

The confetti has been swept up, the champagne glasses packed. Celebration of the ratification of EPCglobal's Gen II standard is over and now many are eager to get standard-compliant products up and running.

I hate to say this, but it might be a little while. RFID hardware manufacturers are in a tough spot - they have two major challenges facing them.First, there are concerns regarding intellectual property patents. EPCglobal states the UHF Generation II Standard is "royalty-free." One company in particular, Intermec (a subsidiary of Unova Corporation) states that the standard violates their intellectual property patents and they expect to collect from any manufacturer of Gen II products. Manufacturers don't know for certain if Gen II products will violate Intermec's IP patents or not. But many have made requests to EPCglobal's legal department and are awaiting clarifying documentation.

Despite the potential legal problems, many manufacturers have begun working on Gen II support products. But this is where they hit problem #2: they can't test the true viability of support products without testing them on Gen II tags - and at this point there are none available. Instead, engineers use something called a 'tag emulator', which is typically a circuit board that functions as an RFID tag. Often, these units are hand built for testing purposes in extremely limited quantities. This situation is akin to building a car but then attempting to test-drive it without any gas.

Okay, so there are still some hurdles to clear. But I think it will be worth the wait, especially when it comes to Gen II tags. They are very sophisticated compared to some of the other RFID tags on the market.

One of my favorite features of Gen II tags is they're "quiet." In environments with numerous tags, a Gen II tag stays quiet unless it is instructed to respond. This makes it easier to search for a specific tag or type of tag in a "tag dense environment." In a distribution center there can literally be thousands of tags in a single read field. Not only does this feature reduce the filtering workload of the middleware, accuracy is drastically improved because only the tag(s) you want respond.

The conversations between reader and tag may occur via open or secure conversations. Gen II tags have a 32-bit access password. If this password is set, then the reader has to have the valid password before the tag will engage in a secured data exchange

Data stored in the tag's memory is logically separated into four distinct banks or areas:
1. Bank one stores reserved memory, which contains the kill and access passwords.
2. The second bank is for the Electronic Product Code (EPC) memory.
3. Bank three holds additional, unique tag identifiers.
4. The forth memory bank is "user memory." This is where user-specific data is stored.

What's most important is that Gen II does not put a limit on the memory size. Tag manufacturers can decide how much memory they want to provide on their tag. There will undoubtedly be multiple offerings with various memory options.

To help appease some of the consumer privacy groups, the "kill" function permanently disables a Gen II tag. A 32-bit kill password is required (different from the access password). Once the reader sends the kill command and password to a tag, the tag responds that the kill operation was successful, and it does not respond again. A kill operation is not reversible.

Gen II tag contents can be locked. The "lock" command allows a reader to lock individual passwords or individual memory banks. There's even a "permalock," which makes contents permanently unchangeable.

So how long will the wait be for Gen II products? Here's my prediction: Stable Gen II products, readers and tags, will be available by the end of the year in quantities sufficient to meet market demand.

Written by Louis Sirico
Copyright ? 2005 Louis Sirico