The electronic Access control (EAC) industry has been around for almost 5 decades now since the advent of magnetic swipe cards. The access technology at the door has evolved from Swipe cards to RFID based proximity cards to NFC cards and now smartphones. But one thing which has not changed in this industry is the back end communication between the readers and controllers. Wiegand protocol has been used for the last 4 decades. Weigand uses a two-wire interface to transmit data between the reader and the controller. This results in a very rigid hardware system that is very heavy on wiring, conduiting and controller panel hardware. Recently the physical security industry has started showing acceptance to cloud-based systems and fully wireless topologies. Wireless mesh is one topology that can be used for a wireless access control system.
Wireless mesh for access control and building automation
Wireless access control system as a concept has been around for a few years now. Standalone solutions powered by Wifi have been deployed by a few manufacturers for small installations where local Wifi availability is there. In a wireless access control system typically the readers act as controllers making the decision of granting access to users. Such systems typically do not need a controller. But for a large commercial multi-tenant project Wifi is not a viable option. With no wires and no controllers, the only way to connect the readers to the access management software is by putting connectivity inside the readers. A wireless mesh topology is best suited for such cases where the readers can communicate with each other over a mesh network. A central edge device called a gateway can then be used as a node in the mesh network to create the connection to the Building LAN or Wifi network. Such systems are best managed using cloud-based software. Bluetooth Low Energy (BLE) Mesh, Zigbee and Thread are a few options available for providing mesh connectivity between readers. In this blog post, we will look at Thread as a connectivity option.