Monday, April 29, 2013

Authentication in Door Access Control Systems

Door Access Control Systems have been around for many years. Recently new technology has increased security by providing better authentication of the person at the door.  Before selecting your system, you should first determine the degree of security you need.  For example, the security level for an office building could be different from a secure military facility.  There is a tradeoff between cost, ease of use and security level provided.   Key-locks were the original method of controlling the door.  It has been around for thousands of years.  The key provided the authentication.  Since a key can be lost or stolen it is not as secure as using more sophisticated biometric authentication system.  Here is a review of the most common methods for authentication and the level of security they provide.

Keypads are probably the least expensive, but also provide the lowest protection.  A PIN number can be forgotten or someone can see the key number entry.  There are two types of keypad systems, one that is included with the lock (sometimes referred to as keyless entry) and another type that includes a separate keypad and electric lock. 
The simple mechanical lock with keypad is primarily designed for home use but can also be used in a small business.  The problem with this system is that it doesn’t have the ability to contain unique numbers so it is difficult to control when there are many people using it.  If someone leaves the organization you have to change the number that everyone else uses. 

The separate keypad is used to control an electric lock on the door.  It is usually used with a central control box that stores an individual code for each person registered in the system.  This system can be used to control access on multiple doors, but it must be used correctly to assure security.  I have seen situations where organizations have issued the same number for everyone.  This type of situation provides very little security.   The database allows you to register each person, and assign the rules about when and where they can enter.  This is more secure but still has problems with stolen numbers and people having to remember the number. 

Card Access Systems
Instead of having each person remember a PIN number, you can provide cards that contain unique codes.  The early readers used bar code, magnetic strip or even Wiegand effect type technology.  
Today most card systems use some type of radio frequency connection and are more secure.  The cards have become credentials that include keyfobs and lanyard style cards and the number is encrypted.   

The latest door access control readers are attached to the network and use standard IP protocols just like computers on the network.  These IP door readers can handle a number of different types of credentials.  The latest “smart cards” not only include unique encrypted numbers but can contain information about the person who holds the credential.  Smart cards such as Mifare type credentials have been used in Europe to pay for transportation.  The credential has built in storage that holds the cash to be used for payment.    

Using credentials is a lot more secure than using a keypad, but there are some concerns about people losing their card or even of higher technology theft of identity using special electronic techniques. 

Security can be increased by adding IP camera systems.  This allows real time and recorded video to be monitored.  

Biometric Authentication
The latest method for authentication is to use a person’s key biometric factors such as fingerprints, voice identification and facial recognition.  This is probably the most secure form of authentication. 

Fingerprint identification:  This has been around for a number of years.  It has become more reliable and less expensive.  You may be familiar with fingerprint identification used by police to catch criminals.  This started out as a manual process but is now automated.  It uses specific characteristics of the fingerprint such as arch, loop and whorl patterns to recognize one print from another.  The same type of identifier is also used in automated access control systems.  Each person is registered in the system using their fingerprints.  The database in the access control system uses the results of the recognition circuits to create a unique pattern for each person.   This pattern can then be compared every time a person uses the system to enter the door. 

There are a number of technologies used to read the fingerprint such as optical, ultrasonic and capacitive.  Each method has pros and cons associated with it.  This system is very secure but there can be problems with reliability.  Dirt and scratches on a finger can deny entry.  

Facial Recognition:  These systems provide an easy way to authenticate a person.  They have gotten much better over the last few years, but there are still some issues with reliability.  For example, if a person comes to the door wearing dark glasses, the system may not be able to recognize them. 

To increase reliability some facial recognition systems have added other biometrics such as Body motion and voice recognition to improve performance.  FST21 Corporation is an example of a multi-modal biometric system that views people as they approach the door.  This provides a much faster analysis and allows people to move quickly through the doorways.  

 It is a challenge for all of us to select the best equipment at the best price.  With that in mind, we continue to review the latest technology from companies all over the world in order to increase our safety and security.   

Please contact us if you need help with your access control systems.  You can contact us at 914-944-3425 or use our contact form.