SIEMENS

From watches, jewelry and clothing to water faucets and brake disks — virtually no product is safe from counterfeiters. Product piracy is a booming business. Dr. Michael Braun, Project Manager for RFID Security Systems at Siemens Corporate Technology in Munich, Germany, estimates that the worldwide economic damage due to counterfeit products amounts to at least €56 billion annually. And he emphasizes that this figure is based on very conservative calculations. The Organization for Economic Cooperation and Development (OECD) in Brussels estimates the figure to be five times higher. Product piracy therefore is a major threat to manufacturers, who face the prospect of immense losses in sales. It is therefore not surprising that they want to prevent such nefarious activities and are striving to protect their products against counterfeiting as effectively as possible — in much the same way as governments protect paper money. Solutions involve the identification of products with color-changing inks, reflective pigments, watermarks, holograms, and bar codes.
The ultimate identification technology uses electronic tags, known as RFID chips (Radio Frequency Identification), which make counterfeiting particularly difficult. RFID operation is based on a secret key that is known both to the chip and to the reader. This approach is therefore referred to as a symmetrical method. Such chips may for instance store encoded product data or a serial number. The reader receives this information by a radio signal and uses the same key to decode the contents.
However, as RFID expert Michael Braun is quick to emphasize, anyone who manages to steal the secret key could hack into this symmetrical security system. "At Siemens we have therefore chosen what's known as the asymmetrical approach, which is based on the public key concept, to develop a counterfeit-resistant system," he says. In this system the reader operates with a commonly accessible public key, which is consequently of no interest to hackers. The RFID tag, on the other hand, contains a private, secret key the chip uses to encode a test inquiry of the reader. This asymmetrical method is presently used, for example, to encode e-mails and digital signatures.
To ensure that the private key isn't copied and transferred to another chip, Siemens researchers have additionally developed an algorithm that interacts with so-called elliptical curves. "The RFID tag gives a different response to each inquiry by the reader. This means that criminals can only clone obsolete information that is of no use in attacking a security system," explains Braun.
But until recently, such methods could not be applied to RFID chips, which have limited computing power. Now, however, Siemens researchers have solved this problem by developing optimized algorithms. Instead of a programmable processor, they use fixed, nonprogrammable circuit elements. This substantially reduces the energy consumption and size of the chip, which are important cost factors. Braun therefore believes this new technology has a great chance of establishing itself in the market for authenticity verification.
And there's another advantage. In addition to providing maximum security, the technology costs only around one-tenth as much as comparable smart card technology. In addition, it can, for instance, be used throughout the entire value chain from supplier to customer for authenticity testing without a database link. Researchers have already developed a prototype and presented it at the CeBIT 2009 computer fair.

RFIDs in the O.R. In the surgery suite of the Klinikum Rechts der Isar, a major medical center in Munich, a patient lies on an operating table with his abdominal cavity open for treatment. The surgeons use sterile pads to stop any bleeding. One pad after another disappears into the fissures and spaces between the organs, only to be removed and discarded soon afterward.
A surgical nurse counts the number of pads she has handed to the surgeons, as well as the number that have accumulated in the waste basket by the end the operation. If the two numbers agree, it's clear that no pad was left behind in the patient. "But despite this safety procedure, in rare cases a pad does get left behind," admits chief surgeon Prof. Hubertus Feußner, who adds that this happens in roughly one out of every 5,000 (mostly abdominal) operations, and can result in a life-threatening infection.
Although aluminum strips have been woven into sterile pads and are visible in x-ray images, forgotten pads may be difficult to see in post-op medical images depending on their position. In 2007 Siemens therefore launched a three-year program in cooperation with Intel, Fujitsu Siemens and the Klinikum Rechts der Isar medical center to develop an RFID system that detects and counts radio chips sewed into the sterile abdominal pads. The system makes it possible to count the number of pads on the preparation tray, in the patient, and in the waste bin. When the operation is completed, the system displays the totals of counted pads on a monitor — and the surgical staff knows exactly where the pads have ended up.
That's the idea. "But there's still quite a bit to be done, before the system is market-ready," cautions Thomas Jell, Head of RFID Delivery at Siemens IT Solutions and Services. For example, development engineers intend to at least double the present wireless range of the radio chips from the present limit of 50 cm. That's especially important in order to allow the reader's antenna underneath the operating table to register an RFID chip in a pad that is inside a very obese patient.
The solution will be to use abdominal pads outfitted with a sewn-in antenna that is several times longer and therefore more effective than the one in the previous prototype.
Another issue involves the RFID's transmitting frequency. By transponding on the standard high frequency of 13.56 MHz, the device could interfere with operating room medical equipment. Jell can now exclude this for Siemens products. "We're in the process of making our system compatible with currently-available operating room equipment," he says.
But that still leaves the fact that some medical devices, such as electrocoagulation systems, emit high-frequency pulses that can interfere with RFID systems. Responding to this challenge, Siemens researchers have developed reader software that simply filters out these brief interruptions.

Tracking Blood. Another major area in which RFID tags could save lives is in monitoring the temperature of donated blood. With this in mind, in 2008, a consortium consisting of Siemens, French blood bag manufacturer MacoPharma, and circuit board manufacturer Schweizer Electronic of Schramberg, Germany, clinically tested a temperature sensor-equipped RFID system in collaboration with the Medical University in Graz.
The newly-developed RFID tags monitor the entire cooling chain of banked blood from donor to recipient and also store additional data, such as the blood group. This is important because blood spoils rapidly when it is stored without effective cooling.
"The system not only records the temperature of every blood bag but also closes the communications gap between donor stations," explains Harald Speletz, who heads the RFID Solutions Department at Siemens Process Automation in Linz, Austria. "Our solution enables complete documentation from vein to vein and substantially improves patient safety. Siemens scientists are committed to making the cooling chain of banked blood completely transparent using this new recording system," he said.
Using this new solution, medical personnel will attach an RFID chip to each blood bag as soon the blood has been donated. And that chip will stay with the blood throughout its life cycle from whole blood to blood cell concentrate — even in the centrifuge. The electronic chip's system, which includes a temperature sensor with a battery, is so robust that it can withstand being spun at a centrifugal force of up to 5,000 g.
"This RFID system for monitoring banked blood is now sufficiently mature to enter the market," says Speletz. So it won't be long before wireless tags help to ensure the safety of a range of medical procedures.