For DOD, one in 1,048,000 is not unique enough
A math problem requires DOD to update 20 major logistics management systems using RFID
- By Bob Brewin
- Mar 25, 2005
A simple math problem related to serial numbers assigned to active Radio Frequency Identification (RFID) required the Defense Department to update 20 major logistics management information systems and just over 1,500 RFID workstations world-wide over the past year.
The Defense Department has used active RFID tags and readers manufactured by Savi Technology Inc. to track and locate the flow of military supplies since 1994. Lee Weaver, assistant product manager for the Army's Product Manager Joint-Automated Identification Technology Office (PM J-IT) said a huge increase in the movement of tagged shipments over the past two years as a result of the Afghanistan and Iraq wars means the DOD will soon run out of unique serial numbers for the tags.
Savi used a 20-bit data store for the RFID tags serial numbers, Weaver said, which meant a total of 1,048,575 unique serial numbers -- a large but finite number which DOD is rapidly approaching due to increased tag use. Weaver said that in order to continue to provide unique serial numbers for active RFID tags, Savi had to move to a 22-bit store for serial numbers, which will provide a pool of roughly three million more serial numbers.
The Savi tags have a 128 kbps data store (roughly 80 pages of text) to identify shipments. Readers used at depots, ports and air hubs interrogate the tags, allowing users of DOD in-transit visibility systems to locate shipments and automatically inventory the contents of containers or pallets.
Reginald Bagby, the J-AIT deputy product manager, said DOD had never envisioned using over a million tags so quickly when active RFID program kicked off a decade ago and the move to 22-bit tags for more serial numbers has had a ripple effect on major DOD logistics information management systems.
Weaver said that in order to correctly process information from the 22-bit Savi tags, PM JAIT had to develop a small piece of Dynamic Link Library (DLL) code that needed to be installed on the major logistics systems as well as 1,517 RFID client workstations worldwide, in a joint effort with the Defense Logistics Agency and the U.S. Transportation Command (USTRANSCOM).
PM J-AIT started working on what Weaver called a 'software patch' to accommodate the 22-bit tags last April, a beta patch in June and final, production patch last October, Weaver said. He added that PM J-AIT and expects to have all systems and workstations upgraded by next month, he said.
Weaver said currently only 55 Savi RFID tag reader workstations have not been upgraded. Col. Tom Hogan, deputy program executive officer for Army Enterprise Information Systems said the workstations not yet upgraded are at sites with low use.
A message on the PM J-AIT Web site to all DOD RFID users said that they also must upgrade middleware used on handheld RFID tag readers manufactured by Intermec Technologies Corp. and Symbol Technologies Inc.
Weaver said only one major logistics system, the Air Force Cargo Movement Operation System still lacks the upgrade, and he expects that to be completed next month. Army Lt. Col. Scott Ross, a USTRANCOM spokesman, concurred, and said he expects all logistics systems will be able to handle the 22-bit tags next month.
While the tag upgrade was literally a two bit problem, the PM J-AIT Web site not updating the RFID software in logistics systems and the readers could have serious consequences, including 'loss of in-transit visibility.'