Blueprint for a Sterile Airport

Near-total airport security is possible. Technologies are in sight to seal the leaks, spot the bad guys, find the bombs.

Illustration by Jameson Simpson

Illustration by Jameson Simpson

AIRPORT SECURITY FOR THE 9/11 AGE

Recent dummy-weapon tests at airports show it's still possible to get guns through security. here's how a super-secure airport would work.

We asked Isotec Inc., a Denver-based security systems design firm, to help us engineer an airport that would target terrorists without gumming up passenger traffic. We also sought input from CompuDyne Corp., Viisage Technology, General Defense Systems, and other companies that make and install security equipment. In this exercise, money was no object; safety was our only concern.

We set a target date of five years from now. But much of the technology is available, or will be very soon. The goal: Every person, every bag, and all supplies and equipment in an airport will be tagged, tracked, and instantly locatable.

1. CHECK-IN AND SECURE ID

Initial safeguards appear a mile outside the airport. Scanners at tollbooth-like structures along access roads aim their laser scanners at vehicles to see if they're carrying explosives. If a soft-drink supply truck is hauling something more volatile than Coke, barriers will prevent it from getting into the airport's secure zone.

First stop for passengers is an ID kiosk, not a ticket agent. A camera and computer linked to facial recognition software process a snapshot. The computer then generates a tamperproof, easily trackable photo-ID smart card with a chip that contains identifying information: flight and gate number, check-in time, as well as a digital version of the facial scan. The scan itself is cross-checked against a database of terrorist suspects.

Meanwhile, at the check-in counter, the passenger swipes the smart card and sensor-equipped tags are attached to baggage and carry-ons. Each of these tags contains a radio frequency identification (RFID) device that emits a faint radio signal and makes a bag locatable at all times, anywhere. The tags are matched to the smart card: If a passenger doesn't board, bags won't either. If a passenger acquires an extra bag along the way, the system knows.

Checked and tagged luggage is examined using a laser scanner that first excites the molecules of items inside the bag, then compares the light those molecules emit against a database of chemical components, looking for suspicious combinations of materials. All flagged bags are shunted to a secure area and an alert is sent to the next checkpoint to detain the passenger bearing the corresponding smart card.

2. CENTRAL COMMAND

Security experts at the airport's command center oversee the system. Monitors linked to the airport's computer network, which processes data from all ID cards, tags, and security devices, alert staff to trouble. Plainclothes agents are dispatched via wireless headsets.

3. SECURITY SCREENING

Passengers approach a streamlined security portal-a corridor made of bulletproof glass with locked doors on either end. The smart card is swiped to gain entry. The passenger's face is scanned again and checked against the ID. An infrared laser similar to the one that examined checked luggage scans carry-ons and clothing. If nothing turns up, the exit door opens and the passenger is free to wander the terminal under the gaze of software-assisted CCTV monitoring. If there's a hitch at the portal-a suspect-list face match, or suspicious materials in a carry-on bag-the passenger is shuttled through a third door, toward another checkpoint. Here an iris scan confirms the passenger's identity; security personnel examine bags by hand. If a passenger is still not cleared, he or she proceeds to a bombproof room, to be met by security personnel.

4. TROUBLE AT THE GATE

The smart card also mediates passenger entry to the jetway. If a problem is detected-a passenger tries to get on the wrong flight, or has unapproved carry-ons-the door won't open and the authorities will investigate the incident. Failure to show up for a flight triggers baggage removal, as does a too-late attempt to board.

5. PLANES AND PERIMETERS

All airport employees pass through a security portal when they report to work: Face or iris scans are matched against a worker database. Lasers scan for explosives or weapons. Employees wear biometric-enhanced RFID badges that control access to authorized zones.

Cameras monitor the airport's perimeter, using algorithms that can distinguish between, say, a dog harmlessly brushing against a fence and a human attempting to climb over it.

Planes will have motion-activated digital video cameras to monitor cargo bays, landing gear, and engines for unauthorized activity. And jets are loaded with hidden cameras-in the cockpit, galleys, and cabins-that record activity during flights and send live feeds to security personnel on the ground, in case, in the event of a security failure, the F15s need to be scrambled.

THE GUTS OF THE SYSTEM
Technology & terminology in the secure airport.

Authentication

The system of verifying that you are who you claim to be, whether you're trying to board a plane or gain access to a computer network. The most secure authentication techniques today rely on a combination of biometrics, passwords, and data-rich identity tokens such as a smart card. Authentication is a key to security systems, but of course can't guarantee that an authenticated person has good intentions.

Biometrics

The science of measuring characteristics unique to each individual (such as fingerprints, facial appearance, voice patterns, striations on the iris, or the arrangement of veins on the retinal wall of the eye), converting them into digital form, and analyzing them. In security zones, these identifiers are usually compared against a database of suspected and known criminals or terrorists. Only retinal and iris scans approach 100 percent accuracy.

Database

A collection of digitized information, such as names, numbers, pictures, or text, that can be searched for specific groups of data, such as birth city and date. Currently there is no national database of U.S. residents; state driver's license databases are not integrated; and there is opposition to creating such a database. As stories about FBI performance before and after 9/11 indicate, the quality of terrorist and criminal databases and related technology at law enforcement agencies is not as robust as it should be.

Iris Recognition

A biometric that measures the unique furrows, wrinkles, and cracks in the iris, the muscular part of the eye that surrounds the pupil. No two irises are identical, making this biometric nearly 100 percent accurate. A digital image of the iris is captured, and numbers are assigned to more than 250 distinct points on the iris. Because the process isn't as fast or convenient as facial recognition, it will most likely be used in airports as a secondary security check and for travelers passing through customs.

Encryption
Techniques for scrambling transmitted data so that only the sender and the intended recipient can read it. This is usually accomplished by systematically modifying data according to a set of rules called a key. Only computers with the right key can unscramble the data. Encryption is commonly used for everything from credit card transactions to satellite communications. In airports, it would keep hackers from reading the information traveling across the facility's security network.

Facial Recognition
A biometric that identifies an individual based on a digitized image of that person's face. One strategy assigns numbers to various characteristics of the face such as the distance between the eyes or the width of the nose. Software can sift through a database of faces to find others with numbers that match. Facial recognition is generally considered 80 to 90 percent accurate under the best circumstances, but can be affected by camera angle, lighting, and changes to a face over time.

Smart Card

A credit-card-size device containing an embedded microchip that can store a large amount of digital data and, in some cases, interact with scanning devices to allow or deny access to certain data. Smart cards can be used for virtually anything, from buying gas to recording biometric information. Cards may contain large-capacity read-write data storage devices, so information can be added (such as new medical conditions, or recent travel destinations). For more on the emerging technology of smart cards, see the story on a national ID card in this issue.

Laser Scanner
Officially called laser-induced breakdown spectroscopy (LIBS), this process shoots a beam of light at an object, exciting its molecules. As the molecules relax, they emit a pattern of light, or spectrum, which is unique for every material. This pattern can be checked against a database of known substances. Similar techniques are used to detect carbon in soil, defects in semiconductors, and tooth decay. In a secure airport, laser scanners would identify materials found in weapons or bombs.

Proximity Card
Using a radio frequency identification (RFID) chip, this tiny transmitter broadcasts a faint radio wave that can trip alarms if a person tries to enter an unauthorized area, unlock doors for people who are allowed to go through, and pinpoint the location of an item. In airports, proximity cards on luggage, matched to a passenger's smart card, will keep track of baggage at all times. They will also be used to control employee access. Smart cards, too, can contain RFIDs, both to track the location of a card and prevent tampering.

THE LITTLE MATTER OF COST
Rendering major U.S. airports sterile could cost hundreds of billions, driving up ticket prices and taxes.

The biggest barrier to our blueprint for a fully secure airport? The price tag. It could cost tens of billions of dollars to upgrade existing terminals in all 429 commercial airports in the U.S., says James Gilliland, an airline bond market analyst at Fitch Ratings. That's an enormous amount of money, considering that the nation's airlines earned only $2.5 billion in 2000, the last year the industry was profitable. Consequently, the effort to build secure airports will likely be funded by higher ticket prices and new taxes. Still, despite the financial obstacles, many airport designers contend that within a decade, terminals protected by some combination of computers, lasers, smart cards, and biometrics will be as common as an airport without metal detectors was just 30 years ago.