Helen of Troy was said to have a “face that launched a thousand ships.” She was an exquisite beauty whose abduction, in the legend at least, started the Trojan War. Today, all of our faces, plain or unassuming as they may be, have the ability to launch a thousand applications, including unlocking phones, aiding forensics investigations, and opening doors. There is a rapidly growing use of face recognition for access control that is quickly replacing other technologies. This technology has its pros and cons, all of which need to be carefully considered as we continue to deploy and develop facial recognition in our buildings.
The journey of access
Today, building and real estate managers have dozens of options for access control, from lock-and-key to Jetson-like technologies. Despite all of the options available, the majority of buildings still use physical locks, their biggest advantages are cost and ease of installation. The drawbacks are that they are binary. Anyone with a key can get inside anytime. Anyone lacking a key cannot. There is no way to allow only certain users access or limit use to certain hours. Plus, they don’t produce records of access, which would enable security to investigate incidents and audit door use.
Stepping a little further into the future are token-based technologies. With token-based systems, presenting a card or fob at a reader releases either an electromechanical or electromagnetic lock, allowing access. The most basic card technology is barcode. It is cheap but extremely vulnerable. A card can be duplicated in seconds. Magnetic stripe cards, which use the same technology as older credit cards, provide somewhat more security than barcodes, but the technology is still easy to defeat. Wiegand cards contain twisted wires and operate via magnetic fields. Much more secure than magstripe or barcode technology, Wiegand was popular decades ago, though applications persist today. The emergence of proximity cards swept away a generation of Wiegand technology. Prox cards, which work by holding a card close to a reader, provide superior security and convenience at lower cost. Smart cards, also referred to as high-frequency radio identification cards, are mini-computers that do far more than grant access. They can function as a debit card and as a SIM phone card, for example. They are very difficult to duplicate.
Now we are seeing the end to the “token” era and the emergence of mobile unlock technologies. Using a mobile phone to unlock doors has a few advantages, including convenience (users forget keycards, not their phones), hygiene, ease of enrollment, and credential management. However, they require Bluetooth-enabled readers while card-based readers typically don’t use Bluetooth.
What could come after mobile tech? There is a good chance it could be biometrics, or using someone’s physical attributes to confirm their identity. The most common being fingerprints, hand geometry, iris pattern and face recognition. Fingerprint technology has existed for more than 100 years. It captures the graphical ridge and valley patterns of the fingerprint and has long been the gold standard of biometrics for its reliability. With organizations turning to frictionless technologies however, touchless fingerprint systems have entered the marketplace. To stick to appendage-based access, the hand geometry approach measures the thickness, length, width, and surface area of the hand. However, hand geometry is not unique and has been around for the better part of 40 years. Moreover, almost all existing systems require contact with a surface.
Face recognition verifies identities using characteristics and features of the face. Technologies include 3-D, vascular and heat-pattern, and skin texture analysis. But, in the most prevalent type of facial recognition, algorithms identify certain points on the face, such as the shape of one’s chin, and create a template for that person. When the person approaches a facial scanner, their live image is captured and converted into a template, which is then compared to the templates stored in the database. A match enables access. Similarly, iris and retina scanning rely on the unique physiological features of the eye to identify and verify individuals. The iris sits at the front of the eye, while the retina is at the back, so retina identification requires a much deeper and more intrusive scan. While iris scanning is less intrusive, retina scanning is more accurate.
Face your fears
With a COVID-obsessed globe, any workplace solution must be sanitary, hygienic, and low touch. Touchless biometrics solutions, most notably face recognition, fit the bill. Face recognition neither requires contact with a reader nor an invasive beam. As with any access control system, the issue is for a user to pass through an access point without having to grip a handle or turn a knob. Some solutions include automatically opening doors, see-through doors that can be pushed open either way by a shoulder or elbow, foot pedals, and turnstiles. Businesses unable to reengineer their offices are providing sanitization stations on either side of every door that requires hand contact to open.
Face recognition technology can also integrate with temperature screening hardware, health and wellness apps, contact tracing systems, PPE inventory systems, and more.
Blink and you’ll miss it. The pace of technological advancement in facial recognition has been blistering. According to the National Institute of Standards and Technology, facial recognition has “undergone an industrial revolution” in the last decade, with “massive gains in accuracy” in recent years. That’s all the more impressive because systems were tested against a database containing more than 26 million portraits. Even the largest companies’ access control systems would need to match only a fraction of that amount.
Further, the frictionless experience is a paramount consideration during a pandemic when health and safety are the highest concerns. With touchless capabilities, carrying a large package and being unable to grab your badge or put your hand into a reader is no longer a concern. Facial readers are almost completely passive including no beams shot into your eyes or subdermal scans. No need to put down what you’re carrying or contort your body to gain access either. They also read, verify, and unlock within split seconds with minimal false positives and false negatives. While truly the technology of the future, it’s important to review all considerations.
Security and privacy go hand in hand, which raises the question of how much are you willing to sacrifice one for the other. Most privacy concerns with face recognition for access control relate to the law enforcement use on a grand scale. In access control, face matches only occur with registered users. And any users who are uncomfortable can choose mobile access credentials. Finally, as with most enterprises, face recognition technology developed pre-COVID, where someone wearing a mask would be an exception. Developers are quickly working on systems that can be as effective and accurate with users in masks. But in the meantime, employees might have to lower their masks to be recognized by the reader.
Helen of Troy started wars with her face, but today, the power of the face is no mere myth. Science has unlocked a bit of the mystery of the physiognomy to advance the way we are able to access secure spaces. Access control is not a new concept and the old technologies that we use today have worked for us for centuries. But, we have new needs when it comes to how we interact with our surroundings. We now need a way for people to be able to unlock doors without touching anything and for records to be kept about who has come and gone from a space. These are pushing our access control system to develop innovative new ways to control access, including facial recognition.