In the beginning, there were the battery operated electromechanical locks. You entered a code into the keypad and if the code was correct, the lock unlocked, permitting retraction of the latch bolt. Over time, additional credentials were introduced, including card-based magnetic stripe, bar code, ferromagnetic and onto proximity, biometric and smart.
Soon after standalone electromechanical locks were introduced, audit trail and date/time functions were added. To retrieve the audit trail, a person had to physically go to each device and retrieve the information using either an infrared printer, data transfer module or handheld Personal Digital Assistant (PDA). Most of these retrieval devices are manufacturer-specific and some are even model-specific.
The next major step was the development of hardwired networked locks. A network allows sharing of information between the locks and the computer, providing the ability to have more users, more powerful options for controlling access and more complete audit trail information.
Networked locks can be divided into two categories: manufacturer specific operating system and software and “open architecture” technology allowing the lock to be operated by any software operating within the lock’s parameters.
Hardwiring provides the potential benefit of real time communication between the computer and the locks, which do not have to be battery powered since wiring is being run and power is only two more wires. When any instructions are programmed at the computer, the affected locks can be updated almost instantaneously. Hardwired networked locks can provide real time audit trail and door status. Networking eliminates the need to program, upload or download changes and audit trails at each lock.
The difficulty with hardwired networked locks is if there is a very long wire run or if there are problems with running wires, costs can be extremely expensive. For example, problem buildings include having reinforced concrete walls, if trenching is required or there is no space above the ceilings.
Hardwired networked locks provide the ability to immediately delete a user, employee or service provider’s credential that has been terminated or lost. A system wide lockdown can be performed on case of an emergency. The lockdown command will usually override all existing programming functions until the emergency no longer exists.
Continuing on the development path, a number of electromechanical lock manufacturers cut the network wires and became wireless while still providing the lock functionality. The lock’s wireless protocol determines the standard (for example 802.15.04, 802.11, 900MHz, 915MHz, etc.), network size, transmission range, data rate, system resources, and average battery life.
Wireless locks include the Corbin Russwin Access Intelligent Wi-Fi Locks, Kaba Access Control E-Plex Series products with wireless capabilities and the Sargent Profile Series v.N2 with Aperio™ Technology. The Sargent Profile Series v.N2 locking devices connect wirelessly between the Aperio hub mounted directly above the opening and the lock. Kaba Access Control E-Plex Wireless Series offer a variety of credentials including proximity cards and DESFire, Mifare, iClass Smart cards.
A wireless electromechanical lock contains a wireless transceiver that communicates with a wireless gateway (node or hub) in place of the wiring. The gateway can be wired to the computer using a standard RJ45 Ethernet connection or wireless using 802.11 B/G. Wireless gateways will have a specified range, which can vary by manufacturer and product line.
The wireless signal between the gateways and the locking devices varies depending upon the lock manufacturer’s specifications. For example, Salto uses the low power radio 802.15.04 receivers operating at 2.4Ghz encrypted with a range of up to 100 feet. Alarm Lock Networx gateways operating at 900MHz span up to 900 feet clear field range. SimonsVoss universal plug and play network radio operates at 915 MHz for wireless transmission, the range is up to 100 feet.