Every day, all of us require access to a variety of different physical spaces. Each of these spaces has a different level of access restriction. Homes, apartments, garages, and gyms are a few examples of the restricted facilities we access on a regular basis. A shared access point is an entrance to a facility to which multiple people require access at varying times throughout the day. Shared access points are everywhere. Parking garages, front doors for apartments, doors to an office building, and gates for gated communities are examples of shared access points that we encounter on a regular basis.
Access control is the selective restriction of access to these shared access points.
Gaining access to a shared access point requires the entrant to present some form of credential that is authenticated at the point of access. Opening a shared access point requires the entrant to have something or to know something. If the entrant possesses a physical device that enables the opening of the access point, the entrant uses that device at the shared access point and access is granted. Examples of “something you have” include: clickers to open gates for gated communities, key cards for door readers at an office building or parking garage, key fobs for office doors and apartment front doors, and physical keys for locks. Shared access points can also require entrants to know something in order to gain entry. Examples of “something you know” include: a four digit code entered on a gate keypad, or for visitors to a gated community with a security guard, the name, address, or apartment number of the resident they are visiting.
Sharing access is difficult. Each type of access mechanism presents its own set of problems when multiple individuals desire entrance passed a single shared access point. Gates and garages that are opened by clickers require the entrant to carry the device within close range of the access point, as the device only works in close proximity. Opening the gate or garage from anywhere beyond close range (remote open) is impossible due to the device’s limited range. Physical keys, key fobs, and key cards must be carried around, and have an even smaller range than clickers. None of these three mechanisms allow remote open of the access point.
Sharing access via mechanisms that require “something you know” is equally difficult, and comes with different problems. In the case of shared gate codes, which are entered on a gate keypad and are common in gated communities, the entrant must remember the code. Infrequent visitors to a gated community often forget a 4 digit string of numbers, and codes are periodically changed by the community owners. The majority of current keypad systems have a single shared code for all residents, so sharing access is equivalent to giving a “master key” to any visitor to the gated community.
In order to ensure the security of gated communities that use passcode access, community managers have two options:
- Each home in the community has its own code. In this scenario, community managers must change codes regularly to ensure the web of people with access doesn’t grow too large. Another problem with this scenario is that large communities become insecure: for a 1000 unit community that utilizes a 4 digit code, any random code has a 1 in 10 chance of working.
- The gated community has a single access code for all residents. The access code must regularly change to keep the web of people with access reasonably small, and each homeowner must regularly update their friends and service professionals with the new code.
Both of these options are inconvenient for homeowners in the gated community, and as a result, community managers rarely change codes. In large gated communities with a code that never changes, the number of non-residents that know the code can grow quickly, as each member of the community often share codes with several non residents. After a few weeks there may be thousands of friends, service professionals, and visitors with access to the community. If a security incident occurs within the community, there is no way to know who was involved or who gave the code to the offender.
Shared access points and sharing access is problematic. Whether the access mechanism is something you have or something you know, each method has a unique problem in balancing convenience and security. Physical access devices like clickers, key cards, key fobs, and physical keys must be carried around, and have short contact points, making remote opening of shared access points impossible. Shared codes are difficult to remember, can be changed, and present several security risks as the code proliferates among entrants.