is not stored in a single place.

"CDLIS is a system AAMVA operates for the states, and all the states use it to check, when somebody comes for a commercial driver's license, whether you have a license in any other jurisdiction," he explained. "The records aren't centralized anywhere, it's a pointer system that when the states initiate a query through AAMVA, AAMVA sends messages to the individual states and gets responses back, then sends them back to the jurisdiction that initiated the query. That's the same type of architecture that would exist for the state-to-state transactions to cover all drivers."

Despite the final rule, the future of Real ID seems unclear. The law severely challenges states' rights while simultaneously saddling states with an estimated $4 billion bill. And as anyone ever remotely familiar with government cost estimates can attest, there is a good chance that number will get a lot higher.

Half the states in the union have either passed or are considering passing laws requiring noncompliance with Real ID, setting the stage for an epic showdown between the states and the federal government. If half the nation refused to carry the only ID the federal government recognizes, what would happen to the airline industry? No one without a Real ID will be able to pass airport security. It's just one of the intriguing questions Real ID presents.

But some states, such as California and Alabama, already issue drivers' licenses that meet almost every technological requirement set forth in the Real ID Act, according to those states' DMVs. For these states, funding deployment and managing tens of millions of DMV appointments will be the biggest challenges.

While it's true DHS issued its final regulations regarding Real ID, the reality is this is just the beginning.

Chad Vander Veen  |  Editor, FutureStructure

Chad Vander Veen is the editor of FutureStructure.com