Controlling access is part of everyday life. People cannot go everywhere and do everything. As a society, we control access in many different ways - physically, mechanically and electromechanically.
Physical access control has been used for many thousands of years. A wall, a locked door and a moat are examples of physically restricting access.
When we physically restrict entry, we must also provide a practical way to gain access. A modern example of physical access control is the doorman in front of a building. The doorman’s job is to provide entry to those who are authorized. The other part of the job involves keeping out those who should not enter. The doorman knows or determines who does and does not gain access. The doorman must be at the door either during business hours or whenever access may be required.
A less expensive form of controlling access is a mechanical lock that performs a similar, however, simpler and less distinguishable method of controlling access. Only the keys with the correct bittings are able to unlock the lock mechanism. The mechanical lock mechanism is not able to determine who or how many people desire or gain access or if the door is left unsecured. In this situation, the mechanical lock offers an all or nothing choice.
An inherent problem with mechanical locks is the ability to give the key to someone else or possibly duplicate the key. High security lock manufacturers offer patent protection for their locks and keys that limit the ability of someone creating a key.
In addition, most mechanical locks can be manipulated and some can be bypassed surreptitiously, leaving no evidence of the unauthorized entry.
Most mechanical locks only require one credential to gain access: the key. There are locks and applications, such as vault door that require two persons, each with a different key or code to be entered in order to gain access. Multiple padlocks using a safety lockout hasp can require up to six padlocks be unlocked and removed in order to gain access.
Locksmiths can electrify a mechanical lock to provide remote access. For example, a receptionist can press a momentary button that unlocks the door locking mechanism, providing access.
We can add a switch to a mechanical mortise lock that activates when a proper key is inserted and rotated retracting the latch bolt. The switch can be used to activate a video camera, shunt an alarm, etc. Depending upon how the switch is wired, it can control the operation of more than one function.
To gain more ways to control and restrict access, we take an electrified lock and add electronics, expanding the capabilities. Probably the first advantage of an electromechanical lock is the choice of electronic credentials. These include a keypad and codes, electronic cards including magstripe, proximity and smart cards, and biometrics including fingerprint, facial characteristics and retina scans. The more exotic the lock’s technology, the more expensive the lock. However, not every facility requires networked locks, biometrics or smart card technology.
An advantage of electromechanical locks is employees, especially maintenance and security personnel, no longer have to carry rings of keys for access.
Mechanical override is an important consideration. If the electronics stop functioning, a mechanical override can be a lifesaver. On the other hand, mechanical override is not monitored on some electromechanical locks, permitting someone to use a key in order to gain access at anytime without a record.
Requiring more than one credential can provide a higher level of security. However, just like unauthorized persons learning methods to bypass mechanical locks, there are people and products that can bypass some of the electromechanical lock technologies. This is another reason for having dual or even triple credentials and adding CCTV for the purpose of making sure the persons who gain access are those who should gain access.
Wireless communication means no wires to transfer the information to a personal computer or to another lock.
Probably one of the most important features of an electromechanical lock is the capability of controlling access offering a choice of authorization credentials.